Long-Term Survival Results of a Randomized Trial Comparing Gemcitabine Plus Cisplatin, With Methotrexate, Vinblastine, Doxorubicin, Plus Cis
http://www.100md.com
《临床肿瘤学》
the Department of Oncology, Aarhus University Hospital, Aarhus
Department of Oncology, Herlev University Hospital, Herlev, Denmark
Northern Centre for Cancer Treatment, Newcastle General Hospital, Newcastle
St Bartholomew’s Hospital, London, United Kingdom
Santa Chiara Hospital
University of Torino, Torino, St Luigi Hospital, Orbassano, Italy
The Princess Margaret Hospital, Toronto, Ontario, Canada
Eli Lilly and Company, Indianapolis, IN
ABSTRACT
PURPOSE: To compare long-term survival in patients with locally advanced or metastatic transitional cell carcinoma (TCC) of the urothelium treated with gemcitabine/cisplatin (GC) or methotrexate/vinblastine/doxorubicin/cisplatin (MVAC).
PATIENTS AND METHODS: Efficacy data from a large randomized phase III study of GC versus MVAC were updated. Time-to-event analyses were performed on the observed distributions of overall and progression-free survival.
RESULTS: A total of 405 patients were randomly assigned: 203 to the GC arm and 202 to the MVAC arm. At the time of analysis, 347 patients had died (GC arm, 176 patients; MVAC arm, 171 patients). Overall survival was similar in both arms (hazard ratio [HR], 1.09; 95% CI, 0.88 to 1.34; P = .66) with a median survival of 14.0 months for GC and 15.2 months for MVAC. The 5-year overall survival rates were 13.0% and 15.3%, respectively (P = .53). The median progression-free survival was 7.7 months for GC and 8.3 months for MVAC, with an HR of 1.09. The 5-year progression-free survival rates were 9.8% and 11.3%, respectively (P = .63). Significant prognostic factors favoring overall survival included performance score (> 70), TNM staging (M0 v M1), low/normal alkaline phosphatase level, number of disease sites ( three), and the absence of visceral metastases. By adjusting for these prognostic factors, the HR was 0.99 for overall survival and 1.01 for progression-free survival. The 5-year overall survival rates for patients with and without visceral metastases were 6.8% and 20.9%, respectively.
CONCLUSION: Long-term overall and progression-free survival after treatment with GC or MVAC are similar. These results strengthen the role of GC as a standard of care in patients with locally advanced or metastatic TCC.
INTRODUCTION
Combination chemotherapy is the treatment of choice for patients with inoperable locally advanced or metastatic bladder cancer. On the basis of superior efficacy in phase III studies, the methotrexate/vinblastine/doxorubicin/cisplatin (MVAC) regimen became frequently used.1-4 However, MVAC treatment is associated with substantial toxicities and a toxic death rate of approximately 3% to 4%.2,3 Thus, a need for alternative therapies that can provide a better survival outcome or a similar survival benefit without the inherent toxicity of the MVAC regimen was identified.
On the basis of encouraging results with gemcitabine and cisplatin (GC) in several phase II bladder cancer studies,5 an international, multicenter, randomized phase III study in 405 patients was performed to compare overall survival between GC- and MVAC-treated patients with locally advanced or metastatic transitional cell carcinoma (TCC) of the urothelium.6 This study showed similar efficacy with regard to overall survival (GC, 13.8 months; MVAC, 14.8 months), time to progressive disease (GC, 7.4 months; MVAC, 7.4 months), and response rate (GC, 49.4%; MVAC, 45.7%); however, a better safety profile was observed with GC, resulting in significantly less febrile neutropenia, neutropenic sepsis, and mucositis than with MVAC. In addition, a recent cost-utility analysis of the GC versus MVAC regimens based on data from the United Kingdom concluded that GC offered reasonable value in this disease setting.7 The detailed results of the GC versus MVAC study have been reported in this journal6 and led to the widespread use and approval of the GC combination in more than 60 countries throughout the world.
The median length of follow-up of the patients in this study at the time of the initial report was 19 months, and uncertainties remained regarding the long-term efficacy of the GC combination, especially compared with MVAC. We therefore performed an updated analysis of overall survival and other time-to-event end points 5 years after the last patient was enrolled onto the study. In addition, as in the initial publication, prespecified patient characteristics were investigated for their importance as prognostic factors. An update on the safety results was not performed, given that all patients had already completed their chemotherapy at the time of the first survival analysis, and therefore, no changes were to be expected from a new analysis.
PATIENTS AND METHODS
Eligibility Criteria
The details of the study have been reported in detail in this journal.6 In summary, eligible patients had measurable or assessable, histologically proven, locally advanced (T4b, N2, or N3) or metastatic (M1) TCC of the urothelium. Prior immunotherapy or chemotherapy was not allowed. Prior local intravesical therapy, radiation, or immunotherapy was permitted if it was completed at least 4 weeks before enrollment. Eligible patients were required to have Karnofsky performance score (PS) of 70 or more, adequate bone marrow reserve (WBC count 3.5 x 109/L, platelets 100 x 109/L, and hemoglobin 10 g/dL) and renal function (creatinine clearance 60 mL/min), and an estimated life expectancy of at least 12 weeks. This study was conducted according to the ethical principles of the Declaration of Helsinki, the applicable guidelines for Good Clinical Practice, or the applicable laws and regulations of the countries where the study was conducted, whichever represented the greater protection of the individual. Written informed consent was obtained from all patients before random assignment.
Patient Characteristics
Patient characteristics were generally well balanced across treatment arms (Table 1). A total of 137 patients had locally advanced disease (34%) and 268 patients had metastatic disease (66%), respectively. Visceral metastases were present in a total of 132 patients (33%).
Study Design and Treatment Evaluation
Patients were randomly assigned to receive either GC or MVAC in this phase III, active controlled, open-label, randomized study. The Pocock and Simon minimization method was used to perform treatment allocation by the Netherlands Cancer Institute.8 Before random assignment, patients were stratified according to the following criteria: PS, stage, visceral metastases, alkaline phosphatase level, prior radiotherapy, measurable disease, and investigator site. Patients in the GC arm were randomly assigned to receive gemcitabine 1,000 mg/m2 during 30 to 60 minutes on days 1, 8, and 15, plus cisplatin 70 mg/m2 on day 2. Patients in the MVAC arm were randomly assigned to receive methotrexate 30 mg/m2 on days 1, 15, and 22; vinblastine 3 mg/m2 on days 2, 15, and 22; doxorubicin 30 mg/m2 on day 2; and cisplatin 70 mg/m2 as a 1- to 8-hour infusion on day 2. Cycles were repeated every 28 days.
In both arms, cycles were not initiated unless WBC was 3.0 x 109/L and platelets were 100 x 109/L. If a cycle was delayed for more than 4 weeks, patients were taken off the study. In the GC arm, gemcitabine doses on day 8 or 15 were omitted for WBC 1.99 x 109/L and platelets 49 x 109/L. In the MVAC arm, methotrexate or vinblastine doses on day 15 or 22 were delayed for WBC 2.9 x 109/L and platelets 74 x 109/L. Doses were adjusted for nonhematologic toxicity, including mucositis, in both study arms. Patients received a maximum of six cycles of treatment unless they experienced disease progression, developed unacceptable toxicity, or the patient, attending physician, or sponsor requested discontinuation.
Supportive care, including blood transfusions, antiemetics, and analgesics, was permitted as appropriate. In the absence of disease progression, palliative radiotherapy was allowed for pre-existing, painful bony lesions. Prophylactic use of growth factors such as filgrastim was not recommended in either arm. No other antineoplastic therapy was permitted during the study.
Blood counts and serum chemistries were performed weekly, and creatinine clearance was calculated before chemotherapy administration. PS was assessed before each cycle, and weight was measured weekly. Tumors were assessed using WHO criteria, and were performed radiologically and by physical examination. Tumors were reassessed every two cycles, and responses were confirmed after at least 4 weeks.
Overall survival was measured from the date of random assignment until death. Patients who had not died or who were lost to follow-up were censored for overall survival when they were last known to be alive. Progression-free survival was measured from the date of random assignment until death or progression. Patients who were alive and who had not experienced disease progression, or who were lost to follow-up, were censored for progression-free survival at the date that they were last known to be alive and progression free.
Statistical Considerations
The Kaplan-Meier method was used to calculate time-to-event end points, which were compared using the log-rank and Wilcoxon tests. For both end points, the 5-year survival rate was computed for each treatment arm using the Kaplan-Meier method and compared based on a normal approximation for the difference between the rates. The Cox proportional hazards model was used to examine the effects of prespecified baseline prognostic factors, including PS, TNM stage, presence of visceral metastases, alkaline phosphatase level, number of disease sites, prior radiotherapy, disease measurability, age, sex, and time to diagnosis. The Wald test was used to calculate P values. Factors that showed individual prognostic value in univariate models were used to examine their joint prognostic value in a multivariate model. A final model was developed using a backward selection strategy. This strategy involved eliminating the factor with the largest nonsignificant P value in a sequential fashion until all factors remaining were statistically significant. Treatment was added to the final model to assess its effect when adjusted for the presence of important prognostic factors.
RESULTS
Between November 1996 and September 1998, 426 patients were entered onto the study. From this group, 405 patients were randomly assigned: 203 to the GC arm and 202 to the MVAC arm. Nineteen patients did not meet protocol entry criteria, one patient died as a result of bladder cancer before random assignment, and one patient did not continue because of personal reasons. For this analysis, the database was locked in April 2004 (ie, more than 5 years after the last patient had been enrolled onto the study).
Long-Term Overall Survival
At the time of our initial analysis,6 274 patients had died (GC, 139 patients; MVAC, 135 patients), producing a censoring rate of 32%. In this survival update, 347 patients had died (GC, 176 patients; MVAC, 171 patients), producing a censoring rate of 14%. As of April 2004, 58 patients were still alive (GC, 27 patients; MVAC, 31 patients); 16 patients in the GC arm and 21 patients in the MVAC arm were still in complete remission. Overall survival was similar on both arms (hazard ratio [HR], 1.09; 95% CI, 0.88 to 1.34; P = .66; Fig 1; Table 2). Median survival was 14.0 months (95% CI, 12.3 to 15.5 months) with GC, and 15.2 months (95% CI, 13.2 to 17.3 months) with MVAC. The differences in survival rates at 24 months (GC, 25.0%; MVAC, 31.0%), 48 months (GC, 16.4%; MVAC, 17.3%), and 60 months (GC, 13.0%; MVAC, 15.3%) were not significant (Table 2).
Univariate analyses were performed on prognostic groups based on several prespecified factors, including PS and visceral metastases (Table 3). A multivariate analysis of all significant prognostic factors was conducted using backward selection to determine the final model. Independent prognostic factors adversely affecting overall survival included PS (> 70), TNM staging (M0 v M1), low/normal alkaline phosphatase expression, number of sites of disease (< three), and the absence of visceral metastasis. When treatment was added to this final model of significant prognostic factors, there was no treatment effect for overall survival. Again, there was a similar survival between the two arms. The adjusted HR for overall survival was 0.99 (95% CI, 0.79 to 1.23; Wald P = .93).
Long-Term Progression-Free Survival
At the time of our initial analysis,6 334 patients had experienced disease progression or died (GC, 171 patients; MVAC, 163 patients), producing a censoring rate of 17.5%. In this updated report, 362 patients had experienced disease progression or died (GC, 184 patients; MVAC, 178 patients), producing a censoring rate of 10.6%. Progression-free survival was similar in the two arms (HR, 1.09; 95% CI, 0.89 to 1.34; P = .63) as shown in Figure 2. The median progression-free survival was 7.7 months with GC (95% CI, 6.8 to 8.8 months) and 8.3 months with MVAC (95% CI, 7.3 to 9.7 months). The differences in progression-free survival rates at 24 months (GC, 13.9%; MVAC, 18.4%), 48 months (GC, 9.8%; MVAC, 12.8%), and 60 months (GC, 9.8%; MVAC, 11.3%) were not significant (Table 4). A multivariate analysis of all significant prognostic factors was conducted using backward selection to determine the final model for progression-free survival. Independent prognostic factors adversely affecting progression-free survival were poor PS (70), high alkaline phosphatase, measurable disease, presence of visceral metastases, TNM staging (M1), and number of disease sites (> three; Table 3). When treatment was added to this final model of significant prognostic factors, there was no treatment effect for progression-free survival. Again, there was a similar progression-free survival in the two arms. The adjusted HR for progression-free survival was 1.01 (95% CI, 0.81 to 1.25; Wald P = .94).
Impact of Prognostic Factors on Long-Term Survival
Baseline Karnofsky PS and the presence of visceral metastases had the highest prognostic value for survival, as indicated in Table 3. Plots of the survival curves for these two important prognostic factors are shown in Figures 3A and 3B. Patients without visceral metastases to bone, liver, or lung had a median overall survival of 18.4 months and a 5-year survival rate of 20.9% (95% CI, 15.3% to 26.5%), whereas patients with visceral metastases had a median overall survival of 10.3 months and 5-year survival rate of 6.8% (95% CI, 3.2% to 10.4%; Fig 3A). Patients with a baseline Karnofsky PS of 70 had a worse outcome, with a median overall survival of 8.3 months and a 5-year survival rate that was inestimable (due to the low number of patients meeting this criteria), whereas patients with a Karnofsky PS of 80 to 100 had a better outcome, with a median overall survival of 16.0 months and a 5-year survival probability of 16.5% (Fig 3B).
DISCUSSION
Long-term survival of patients with advanced bladder cancer is uncommon, although this disease remains amenable to chemotherapeutic intervention. We report herein on the 5-year survival of patients with locally advanced or metastatic bladder cancer comparing GC with MVAC treatment in a large, international, multicenter phase III study. This analysis confirms that some patients can achieve long-term disease control and possible cure with systemic chemotherapy. It also supports the earlier conclusions that GC provides similar efficacy in terms of overall survival and progression-free survival compared with MVAC in this patient population but does so with a superior safety profile.6 These long-term results provide additional support for GC as a standard of care in patients with locally advanced and metastatic bladder cancer. However, it should be emphasized that this conclusion cannot be translated to the adjuvant setting. Thus, administration of GC as neoadjuvant or adjuvant treatment should be explored further within the framework of clinical trials.
The data also corroborate findings by Stadler et al,9 who analyzed the long-term survival in the three initial and previously published phase II bladder cancer trials10-12 in which patients were treated with GC. The overall median survival of 121 patients was 13.2 months, and the estimated 4-year survival was 13% ± 6%, comparable to those observed in this larger phase III study directly comparing GC and MVAC.
The results of our univariate analysis are in line with the findings by Bajorin et al,13 who defined Karnofsky PS and presence or absence of visceral metastases as important, independent prognostic variables.13,14 The final results of this phase III study, the largest study done so far in locally advanced and metastatic bladder cancer, confirm the prognostic value of these two pretreatment characteristics for overall survival. In addition, in our study, elevated alkaline phosphatase, in accordance with a study by Sengelov et al,15 as well as the number of disease sites (> three v three) also had prognostic value for survival.
When treatment was added in the final multiple regression model, the HR for overall survival (0.99) and progression-free survival (1.01) indicated identical efficacy of both treatment regimens. Although this phase III study was not designed as an equivalence trial, the long-term overall survival results demonstrate the similar efficacy of the GC and MVAC regimens in patients with locally advanced and metastatic bladder cancer. Subgroup analyses of relevant prognostic factors did not disclose any statistically significant differences between GC- and MVAC-treated patients.
In summary, the increasing acceptance and use of GC in patients with locally advanced and metastatic bladder cancer is supported by its similar clinical efficacy compared with MVAC. The 5-year survival data, along with the better tolerability and safety profile of the GC combination, continues to support and strengthen the conclusion6 that the GC regimen is a safe and effective alternative to MVAC therapy in this patient population. However, more efficacious treatment regimens need to be developed16 to increase the long-term survival probability of patients with inoperable locally advanced and metastatic urothelial cancer.
Authors' Disclosures of Potential Conflicts of Interest
The following authors or their immediate family members have indicated a financial interest. No conflict exists for drugs or devices used in a study if they are not being evaluated as part of the investigation. Employment: Annamaria Zimmermann, Eli Lilly; Michael Arning, Eli Lilly. Consultant/Advisory Role: Malcolm Moore, Eli Lilly. Stock Ownership: Annamaria Zimmermann, Eli Lilly; Michael Arning, Eli Lilly. Honoraria: Hans von der Maase, Eli Lilly; Luigi Dogliotti, Eli Lilly; Malcolm Moore, Eli Lilly. For a detailed description of these categories, or for more information about ASCO's conflict of interest policy, please refer to the Author Disclosure Declaration and Disclosures of Potential Conflicts of Interest found in Information for Contributors in the front of each issue.
Acknowledgment
We thank David Ohannesian, PhD, for assistance with the manuscript.
NOTES
Supported by a grant from Eli Lilly and Company.
Authors' disclosures of potential conflicts of interest are found at the end of this article.
REFERENCES
Sternberg CN, Yagoda A, Scher HI, et al: Preliminary results of M-VAC (methotrexate, vinblastine, doxorubicin and cisplatin) for transitional cell carcinoma of the urothelium. J Urol 133:403-407, 1985
Loehrer PJ Sr, Einhorn LH, Elson PJ, et al: A randomized comparison of cisplatin alone or in combination with methotrexate, vinblastine, and doxorubicin in patients with metastatic urothelial carcinoma: A cooperative group study. J Clin Oncol 10:1066-1073, 1992
Sternberg CN, Yagoda A, Scher HI, et al: Methotrexate, vinblastine, doxorubicin, and cisplatin for advanced transitional cell carcinoma of the urothelial: Efficacy and patterns of response and relapse. Cancer 64:2448-2458, 1989
Saxman SB, Propert KJ, Einhorn LH, et al: Long-term follow-up of a phase III intergroup study of cisplatin alone or in combination with methotrexate, vinblastine, and doxorubicin in patients with metastatic urothelial carcinoma: A cooperative group study. J Clin Oncol 15:2564-2569, 1997
von der Maase H: Gemcitabine in transitional cell carcinoma of the urothelium. Expert Rev Anticancer Ther 3:11-19, 2003
von der Maase H, Hansen SW, Roberts JT, et al: Gemcitabine and cisplatin versus methotrexate, vinblastine, doxorubicin, and cisplatin in advanced or metastatic bladder cancer: Results of a large, randomized, multinational, multicenter, phase III study. J Clin Oncol 18:3068-3077, 2000
Robinson P, von der Maase H, Bhalla S, et al: Cost-utility analysis of the GC versus MVAC regimens for the treatment of locally advanced or metastatic bladder cancer. Expert Rev Pharmacoeconomics Outcomes Res 4:27-38, 2004
Pocock SJ, Simon R: Sequential treatment assignment with balancing for prognostic factors in the controlled clinical trial. Biometrics 31:103-115, 1975
Stadler WM, Hayden A, von der Maase H, et al: Long-term survival in phase II trials of gemcitabine plus cisplatin for advanced transitional cell cancer. Urol Oncol 7:153-157, 2002
von der Maase H, Andersen L, Crino L, et al: Weekly gemcitabine and cisplatin combination therapy in patients with transitional cell carcinoma of the urothelium: A phase II clinical trial. Ann Oncol 10:1461-1465, 1999
Moore MJ, Winquist EW, Murray N, et al: Gemcitabine plus cisplatin, an active regimen in advanced urothelial cancer: A phase II trial of the National Cancer Institute of Canada Clinical Trials Group. J Clin Oncol 17:2876-2881, 1999
Kaufman D, Raghavan D, Carducci M, et al: Phase II trial of gemcitabine plus cisplatin in patients with metastatic urothelial cancer. J Clin Oncol 18:1921-1927, 2000
Bajorin DF, Dodd PM, Mazumdar M, et al: Long-term survival in metastatic transitional-cell carcinoma and prognostic factors predicting outcome of therapy. J Clin Oncol 17:3173-3181, 1999
Bajorin D: The phase III candidate: Can we improve the science of selection J Clin Oncol 22:211-213, 2004
Sengelov L, Kamby C, von der Maase H: Metastatic urothelial cancer: Evaluation of prognostic factors and change in prognosis during the last twenty years. Eur Urol 39:634-642, 2001
von der Maase H, Sengelov L: Chemotherapy in locally advanced and metastatic bladder cancer. Am J Cancer 4:1-13, 2005(Hans von der Maase, Lisa )
Department of Oncology, Herlev University Hospital, Herlev, Denmark
Northern Centre for Cancer Treatment, Newcastle General Hospital, Newcastle
St Bartholomew’s Hospital, London, United Kingdom
Santa Chiara Hospital
University of Torino, Torino, St Luigi Hospital, Orbassano, Italy
The Princess Margaret Hospital, Toronto, Ontario, Canada
Eli Lilly and Company, Indianapolis, IN
ABSTRACT
PURPOSE: To compare long-term survival in patients with locally advanced or metastatic transitional cell carcinoma (TCC) of the urothelium treated with gemcitabine/cisplatin (GC) or methotrexate/vinblastine/doxorubicin/cisplatin (MVAC).
PATIENTS AND METHODS: Efficacy data from a large randomized phase III study of GC versus MVAC were updated. Time-to-event analyses were performed on the observed distributions of overall and progression-free survival.
RESULTS: A total of 405 patients were randomly assigned: 203 to the GC arm and 202 to the MVAC arm. At the time of analysis, 347 patients had died (GC arm, 176 patients; MVAC arm, 171 patients). Overall survival was similar in both arms (hazard ratio [HR], 1.09; 95% CI, 0.88 to 1.34; P = .66) with a median survival of 14.0 months for GC and 15.2 months for MVAC. The 5-year overall survival rates were 13.0% and 15.3%, respectively (P = .53). The median progression-free survival was 7.7 months for GC and 8.3 months for MVAC, with an HR of 1.09. The 5-year progression-free survival rates were 9.8% and 11.3%, respectively (P = .63). Significant prognostic factors favoring overall survival included performance score (> 70), TNM staging (M0 v M1), low/normal alkaline phosphatase level, number of disease sites ( three), and the absence of visceral metastases. By adjusting for these prognostic factors, the HR was 0.99 for overall survival and 1.01 for progression-free survival. The 5-year overall survival rates for patients with and without visceral metastases were 6.8% and 20.9%, respectively.
CONCLUSION: Long-term overall and progression-free survival after treatment with GC or MVAC are similar. These results strengthen the role of GC as a standard of care in patients with locally advanced or metastatic TCC.
INTRODUCTION
Combination chemotherapy is the treatment of choice for patients with inoperable locally advanced or metastatic bladder cancer. On the basis of superior efficacy in phase III studies, the methotrexate/vinblastine/doxorubicin/cisplatin (MVAC) regimen became frequently used.1-4 However, MVAC treatment is associated with substantial toxicities and a toxic death rate of approximately 3% to 4%.2,3 Thus, a need for alternative therapies that can provide a better survival outcome or a similar survival benefit without the inherent toxicity of the MVAC regimen was identified.
On the basis of encouraging results with gemcitabine and cisplatin (GC) in several phase II bladder cancer studies,5 an international, multicenter, randomized phase III study in 405 patients was performed to compare overall survival between GC- and MVAC-treated patients with locally advanced or metastatic transitional cell carcinoma (TCC) of the urothelium.6 This study showed similar efficacy with regard to overall survival (GC, 13.8 months; MVAC, 14.8 months), time to progressive disease (GC, 7.4 months; MVAC, 7.4 months), and response rate (GC, 49.4%; MVAC, 45.7%); however, a better safety profile was observed with GC, resulting in significantly less febrile neutropenia, neutropenic sepsis, and mucositis than with MVAC. In addition, a recent cost-utility analysis of the GC versus MVAC regimens based on data from the United Kingdom concluded that GC offered reasonable value in this disease setting.7 The detailed results of the GC versus MVAC study have been reported in this journal6 and led to the widespread use and approval of the GC combination in more than 60 countries throughout the world.
The median length of follow-up of the patients in this study at the time of the initial report was 19 months, and uncertainties remained regarding the long-term efficacy of the GC combination, especially compared with MVAC. We therefore performed an updated analysis of overall survival and other time-to-event end points 5 years after the last patient was enrolled onto the study. In addition, as in the initial publication, prespecified patient characteristics were investigated for their importance as prognostic factors. An update on the safety results was not performed, given that all patients had already completed their chemotherapy at the time of the first survival analysis, and therefore, no changes were to be expected from a new analysis.
PATIENTS AND METHODS
Eligibility Criteria
The details of the study have been reported in detail in this journal.6 In summary, eligible patients had measurable or assessable, histologically proven, locally advanced (T4b, N2, or N3) or metastatic (M1) TCC of the urothelium. Prior immunotherapy or chemotherapy was not allowed. Prior local intravesical therapy, radiation, or immunotherapy was permitted if it was completed at least 4 weeks before enrollment. Eligible patients were required to have Karnofsky performance score (PS) of 70 or more, adequate bone marrow reserve (WBC count 3.5 x 109/L, platelets 100 x 109/L, and hemoglobin 10 g/dL) and renal function (creatinine clearance 60 mL/min), and an estimated life expectancy of at least 12 weeks. This study was conducted according to the ethical principles of the Declaration of Helsinki, the applicable guidelines for Good Clinical Practice, or the applicable laws and regulations of the countries where the study was conducted, whichever represented the greater protection of the individual. Written informed consent was obtained from all patients before random assignment.
Patient Characteristics
Patient characteristics were generally well balanced across treatment arms (Table 1). A total of 137 patients had locally advanced disease (34%) and 268 patients had metastatic disease (66%), respectively. Visceral metastases were present in a total of 132 patients (33%).
Study Design and Treatment Evaluation
Patients were randomly assigned to receive either GC or MVAC in this phase III, active controlled, open-label, randomized study. The Pocock and Simon minimization method was used to perform treatment allocation by the Netherlands Cancer Institute.8 Before random assignment, patients were stratified according to the following criteria: PS, stage, visceral metastases, alkaline phosphatase level, prior radiotherapy, measurable disease, and investigator site. Patients in the GC arm were randomly assigned to receive gemcitabine 1,000 mg/m2 during 30 to 60 minutes on days 1, 8, and 15, plus cisplatin 70 mg/m2 on day 2. Patients in the MVAC arm were randomly assigned to receive methotrexate 30 mg/m2 on days 1, 15, and 22; vinblastine 3 mg/m2 on days 2, 15, and 22; doxorubicin 30 mg/m2 on day 2; and cisplatin 70 mg/m2 as a 1- to 8-hour infusion on day 2. Cycles were repeated every 28 days.
In both arms, cycles were not initiated unless WBC was 3.0 x 109/L and platelets were 100 x 109/L. If a cycle was delayed for more than 4 weeks, patients were taken off the study. In the GC arm, gemcitabine doses on day 8 or 15 were omitted for WBC 1.99 x 109/L and platelets 49 x 109/L. In the MVAC arm, methotrexate or vinblastine doses on day 15 or 22 were delayed for WBC 2.9 x 109/L and platelets 74 x 109/L. Doses were adjusted for nonhematologic toxicity, including mucositis, in both study arms. Patients received a maximum of six cycles of treatment unless they experienced disease progression, developed unacceptable toxicity, or the patient, attending physician, or sponsor requested discontinuation.
Supportive care, including blood transfusions, antiemetics, and analgesics, was permitted as appropriate. In the absence of disease progression, palliative radiotherapy was allowed for pre-existing, painful bony lesions. Prophylactic use of growth factors such as filgrastim was not recommended in either arm. No other antineoplastic therapy was permitted during the study.
Blood counts and serum chemistries were performed weekly, and creatinine clearance was calculated before chemotherapy administration. PS was assessed before each cycle, and weight was measured weekly. Tumors were assessed using WHO criteria, and were performed radiologically and by physical examination. Tumors were reassessed every two cycles, and responses were confirmed after at least 4 weeks.
Overall survival was measured from the date of random assignment until death. Patients who had not died or who were lost to follow-up were censored for overall survival when they were last known to be alive. Progression-free survival was measured from the date of random assignment until death or progression. Patients who were alive and who had not experienced disease progression, or who were lost to follow-up, were censored for progression-free survival at the date that they were last known to be alive and progression free.
Statistical Considerations
The Kaplan-Meier method was used to calculate time-to-event end points, which were compared using the log-rank and Wilcoxon tests. For both end points, the 5-year survival rate was computed for each treatment arm using the Kaplan-Meier method and compared based on a normal approximation for the difference between the rates. The Cox proportional hazards model was used to examine the effects of prespecified baseline prognostic factors, including PS, TNM stage, presence of visceral metastases, alkaline phosphatase level, number of disease sites, prior radiotherapy, disease measurability, age, sex, and time to diagnosis. The Wald test was used to calculate P values. Factors that showed individual prognostic value in univariate models were used to examine their joint prognostic value in a multivariate model. A final model was developed using a backward selection strategy. This strategy involved eliminating the factor with the largest nonsignificant P value in a sequential fashion until all factors remaining were statistically significant. Treatment was added to the final model to assess its effect when adjusted for the presence of important prognostic factors.
RESULTS
Between November 1996 and September 1998, 426 patients were entered onto the study. From this group, 405 patients were randomly assigned: 203 to the GC arm and 202 to the MVAC arm. Nineteen patients did not meet protocol entry criteria, one patient died as a result of bladder cancer before random assignment, and one patient did not continue because of personal reasons. For this analysis, the database was locked in April 2004 (ie, more than 5 years after the last patient had been enrolled onto the study).
Long-Term Overall Survival
At the time of our initial analysis,6 274 patients had died (GC, 139 patients; MVAC, 135 patients), producing a censoring rate of 32%. In this survival update, 347 patients had died (GC, 176 patients; MVAC, 171 patients), producing a censoring rate of 14%. As of April 2004, 58 patients were still alive (GC, 27 patients; MVAC, 31 patients); 16 patients in the GC arm and 21 patients in the MVAC arm were still in complete remission. Overall survival was similar on both arms (hazard ratio [HR], 1.09; 95% CI, 0.88 to 1.34; P = .66; Fig 1; Table 2). Median survival was 14.0 months (95% CI, 12.3 to 15.5 months) with GC, and 15.2 months (95% CI, 13.2 to 17.3 months) with MVAC. The differences in survival rates at 24 months (GC, 25.0%; MVAC, 31.0%), 48 months (GC, 16.4%; MVAC, 17.3%), and 60 months (GC, 13.0%; MVAC, 15.3%) were not significant (Table 2).
Univariate analyses were performed on prognostic groups based on several prespecified factors, including PS and visceral metastases (Table 3). A multivariate analysis of all significant prognostic factors was conducted using backward selection to determine the final model. Independent prognostic factors adversely affecting overall survival included PS (> 70), TNM staging (M0 v M1), low/normal alkaline phosphatase expression, number of sites of disease (< three), and the absence of visceral metastasis. When treatment was added to this final model of significant prognostic factors, there was no treatment effect for overall survival. Again, there was a similar survival between the two arms. The adjusted HR for overall survival was 0.99 (95% CI, 0.79 to 1.23; Wald P = .93).
Long-Term Progression-Free Survival
At the time of our initial analysis,6 334 patients had experienced disease progression or died (GC, 171 patients; MVAC, 163 patients), producing a censoring rate of 17.5%. In this updated report, 362 patients had experienced disease progression or died (GC, 184 patients; MVAC, 178 patients), producing a censoring rate of 10.6%. Progression-free survival was similar in the two arms (HR, 1.09; 95% CI, 0.89 to 1.34; P = .63) as shown in Figure 2. The median progression-free survival was 7.7 months with GC (95% CI, 6.8 to 8.8 months) and 8.3 months with MVAC (95% CI, 7.3 to 9.7 months). The differences in progression-free survival rates at 24 months (GC, 13.9%; MVAC, 18.4%), 48 months (GC, 9.8%; MVAC, 12.8%), and 60 months (GC, 9.8%; MVAC, 11.3%) were not significant (Table 4). A multivariate analysis of all significant prognostic factors was conducted using backward selection to determine the final model for progression-free survival. Independent prognostic factors adversely affecting progression-free survival were poor PS (70), high alkaline phosphatase, measurable disease, presence of visceral metastases, TNM staging (M1), and number of disease sites (> three; Table 3). When treatment was added to this final model of significant prognostic factors, there was no treatment effect for progression-free survival. Again, there was a similar progression-free survival in the two arms. The adjusted HR for progression-free survival was 1.01 (95% CI, 0.81 to 1.25; Wald P = .94).
Impact of Prognostic Factors on Long-Term Survival
Baseline Karnofsky PS and the presence of visceral metastases had the highest prognostic value for survival, as indicated in Table 3. Plots of the survival curves for these two important prognostic factors are shown in Figures 3A and 3B. Patients without visceral metastases to bone, liver, or lung had a median overall survival of 18.4 months and a 5-year survival rate of 20.9% (95% CI, 15.3% to 26.5%), whereas patients with visceral metastases had a median overall survival of 10.3 months and 5-year survival rate of 6.8% (95% CI, 3.2% to 10.4%; Fig 3A). Patients with a baseline Karnofsky PS of 70 had a worse outcome, with a median overall survival of 8.3 months and a 5-year survival rate that was inestimable (due to the low number of patients meeting this criteria), whereas patients with a Karnofsky PS of 80 to 100 had a better outcome, with a median overall survival of 16.0 months and a 5-year survival probability of 16.5% (Fig 3B).
DISCUSSION
Long-term survival of patients with advanced bladder cancer is uncommon, although this disease remains amenable to chemotherapeutic intervention. We report herein on the 5-year survival of patients with locally advanced or metastatic bladder cancer comparing GC with MVAC treatment in a large, international, multicenter phase III study. This analysis confirms that some patients can achieve long-term disease control and possible cure with systemic chemotherapy. It also supports the earlier conclusions that GC provides similar efficacy in terms of overall survival and progression-free survival compared with MVAC in this patient population but does so with a superior safety profile.6 These long-term results provide additional support for GC as a standard of care in patients with locally advanced and metastatic bladder cancer. However, it should be emphasized that this conclusion cannot be translated to the adjuvant setting. Thus, administration of GC as neoadjuvant or adjuvant treatment should be explored further within the framework of clinical trials.
The data also corroborate findings by Stadler et al,9 who analyzed the long-term survival in the three initial and previously published phase II bladder cancer trials10-12 in which patients were treated with GC. The overall median survival of 121 patients was 13.2 months, and the estimated 4-year survival was 13% ± 6%, comparable to those observed in this larger phase III study directly comparing GC and MVAC.
The results of our univariate analysis are in line with the findings by Bajorin et al,13 who defined Karnofsky PS and presence or absence of visceral metastases as important, independent prognostic variables.13,14 The final results of this phase III study, the largest study done so far in locally advanced and metastatic bladder cancer, confirm the prognostic value of these two pretreatment characteristics for overall survival. In addition, in our study, elevated alkaline phosphatase, in accordance with a study by Sengelov et al,15 as well as the number of disease sites (> three v three) also had prognostic value for survival.
When treatment was added in the final multiple regression model, the HR for overall survival (0.99) and progression-free survival (1.01) indicated identical efficacy of both treatment regimens. Although this phase III study was not designed as an equivalence trial, the long-term overall survival results demonstrate the similar efficacy of the GC and MVAC regimens in patients with locally advanced and metastatic bladder cancer. Subgroup analyses of relevant prognostic factors did not disclose any statistically significant differences between GC- and MVAC-treated patients.
In summary, the increasing acceptance and use of GC in patients with locally advanced and metastatic bladder cancer is supported by its similar clinical efficacy compared with MVAC. The 5-year survival data, along with the better tolerability and safety profile of the GC combination, continues to support and strengthen the conclusion6 that the GC regimen is a safe and effective alternative to MVAC therapy in this patient population. However, more efficacious treatment regimens need to be developed16 to increase the long-term survival probability of patients with inoperable locally advanced and metastatic urothelial cancer.
Authors' Disclosures of Potential Conflicts of Interest
The following authors or their immediate family members have indicated a financial interest. No conflict exists for drugs or devices used in a study if they are not being evaluated as part of the investigation. Employment: Annamaria Zimmermann, Eli Lilly; Michael Arning, Eli Lilly. Consultant/Advisory Role: Malcolm Moore, Eli Lilly. Stock Ownership: Annamaria Zimmermann, Eli Lilly; Michael Arning, Eli Lilly. Honoraria: Hans von der Maase, Eli Lilly; Luigi Dogliotti, Eli Lilly; Malcolm Moore, Eli Lilly. For a detailed description of these categories, or for more information about ASCO's conflict of interest policy, please refer to the Author Disclosure Declaration and Disclosures of Potential Conflicts of Interest found in Information for Contributors in the front of each issue.
Acknowledgment
We thank David Ohannesian, PhD, for assistance with the manuscript.
NOTES
Supported by a grant from Eli Lilly and Company.
Authors' disclosures of potential conflicts of interest are found at the end of this article.
REFERENCES
Sternberg CN, Yagoda A, Scher HI, et al: Preliminary results of M-VAC (methotrexate, vinblastine, doxorubicin and cisplatin) for transitional cell carcinoma of the urothelium. J Urol 133:403-407, 1985
Loehrer PJ Sr, Einhorn LH, Elson PJ, et al: A randomized comparison of cisplatin alone or in combination with methotrexate, vinblastine, and doxorubicin in patients with metastatic urothelial carcinoma: A cooperative group study. J Clin Oncol 10:1066-1073, 1992
Sternberg CN, Yagoda A, Scher HI, et al: Methotrexate, vinblastine, doxorubicin, and cisplatin for advanced transitional cell carcinoma of the urothelial: Efficacy and patterns of response and relapse. Cancer 64:2448-2458, 1989
Saxman SB, Propert KJ, Einhorn LH, et al: Long-term follow-up of a phase III intergroup study of cisplatin alone or in combination with methotrexate, vinblastine, and doxorubicin in patients with metastatic urothelial carcinoma: A cooperative group study. J Clin Oncol 15:2564-2569, 1997
von der Maase H: Gemcitabine in transitional cell carcinoma of the urothelium. Expert Rev Anticancer Ther 3:11-19, 2003
von der Maase H, Hansen SW, Roberts JT, et al: Gemcitabine and cisplatin versus methotrexate, vinblastine, doxorubicin, and cisplatin in advanced or metastatic bladder cancer: Results of a large, randomized, multinational, multicenter, phase III study. J Clin Oncol 18:3068-3077, 2000
Robinson P, von der Maase H, Bhalla S, et al: Cost-utility analysis of the GC versus MVAC regimens for the treatment of locally advanced or metastatic bladder cancer. Expert Rev Pharmacoeconomics Outcomes Res 4:27-38, 2004
Pocock SJ, Simon R: Sequential treatment assignment with balancing for prognostic factors in the controlled clinical trial. Biometrics 31:103-115, 1975
Stadler WM, Hayden A, von der Maase H, et al: Long-term survival in phase II trials of gemcitabine plus cisplatin for advanced transitional cell cancer. Urol Oncol 7:153-157, 2002
von der Maase H, Andersen L, Crino L, et al: Weekly gemcitabine and cisplatin combination therapy in patients with transitional cell carcinoma of the urothelium: A phase II clinical trial. Ann Oncol 10:1461-1465, 1999
Moore MJ, Winquist EW, Murray N, et al: Gemcitabine plus cisplatin, an active regimen in advanced urothelial cancer: A phase II trial of the National Cancer Institute of Canada Clinical Trials Group. J Clin Oncol 17:2876-2881, 1999
Kaufman D, Raghavan D, Carducci M, et al: Phase II trial of gemcitabine plus cisplatin in patients with metastatic urothelial cancer. J Clin Oncol 18:1921-1927, 2000
Bajorin DF, Dodd PM, Mazumdar M, et al: Long-term survival in metastatic transitional-cell carcinoma and prognostic factors predicting outcome of therapy. J Clin Oncol 17:3173-3181, 1999
Bajorin D: The phase III candidate: Can we improve the science of selection J Clin Oncol 22:211-213, 2004
Sengelov L, Kamby C, von der Maase H: Metastatic urothelial cancer: Evaluation of prognostic factors and change in prognosis during the last twenty years. Eur Urol 39:634-642, 2001
von der Maase H, Sengelov L: Chemotherapy in locally advanced and metastatic bladder cancer. Am J Cancer 4:1-13, 2005(Hans von der Maase, Lisa )