Prostate Cancer with Low PSA Levels
http://www.100md.com
《新英格兰医药杂志》
To the Editor: Thompson et al. (May 27 issue)1 have provided a fascinating picture of the prevalence of prostate cancer in men with "normal" prostate-specific antigen (PSA) levels in the Prostate Cancer Prevention Trial. They found surprisingly high rates of prostate cancer in men with PSA values of 4.0 ng per milliliter or less. Many authors have pointed out that PSA screening is flawed because of its relatively poor sensitivity and specificity.2 One potential strategy to improve the sensitivity of PSA evaluations in the context of metastatic disease includes "PSA velocity," or PSA doubling times.3 Since the Prostate Cancer Prevention Trial has annual data on subjects with normal PSA determinations, it would be of interest to know what the PSA doubling time was for those in whom prostate cancer eventually developed in this otherwise low-risk group, as compared with the doubling time for the members of the cohort, in whom prostate cancer did not develop. Doubling times may give some useful insight into this population of men with otherwise silent prostate cancer.
Peter A. Beatty, M.D.
University of Wisconsin Medical Foundation
Madison, WI 53715
peter.beatty@uwmf.wisc.edu
References
Thompson IA, Pauler DK, Goodman PJ, et al. Prevalence of prostate cancer among men with a prostate-specific antigen level of 4.0 ng per milliliter. N Engl J Med 2004;350:2239-2246.
Barry MJ. Prostate-specific-antigen testing for early diagnosis of prostate cancer. N Engl J Med 2001;344:1373-1377.
Patel A, Dorey F, Franklin J, deKernion JB. Recurrence patterns after radical retropubic prostatectomy: clinical usefulness of prostate specific antigen doubling times and log slope of prostate specific antigen. J Urol 1997;158:1441-1445.
To the Editor: As noted by Thompson et al., a lower PSA threshold for recommending biopsy would allow more prostate cancers to be detected but would also increase the number of unnecessary biopsies. One method of improving the power of the PSA test is to measure free PSA; the higher the fraction of free PSA, the lower the risk of prostate cancer.
The Mayo Clinic guidelines state that when the total PSA level ranges from 2.0 to 3.9 ng per milliliter and free PSA makes up more than 18 percent of the total, the risk of prostate cancer is less than 10 percent. When the total PSA level ranges from 2.0 to 3.9 ng per milliliter and free PSA makes up less than 10 percent of the total, the risk of prostate cancer is more than 30 percent.
I believe that a biopsy should be recommended if the total PSA level is 2.0 ng per milliliter or higher and the fraction of free PSA is less than 10 percent of the total.
Alan I. Glaser, M.D.
Newton-Wellesley Hospital
Newton, MA 02462
md.glal@nwh.org
To the Editor: Thompson et al. show that 15.2 percent of men without clinical risk factors have prostate cancer. However, clinically significant prostate cancer has been defined as a tumor with a volume greater than 0.5 cm3 and a Gleason score greater than or equal to 7.1
In the study by Thompson et al., 67 of 449 men with biopsy-proven prostate cancer (14.9 percent) had high-grade disease; however, a low tumor burden on needle biopsy does not necessarily indicate a low tumor volume or a low stage of cancer.2 Hautmann et al. analyzed 133 cystoprostatectomy specimens from men with PSA levels below 4.0 ng per milliliter; 44 percent had prostate cancer and 12 percent had a tumor volume of 0.5 cm3 or greater.3 Extrapolating these data, about 350 of the 2950 patients in the study of Thompson et al. could be affected by clinically significant prostate cancer.
Bernardo Rocco, M.D.
Deliu Victor Matei, M.D.
Ottavio de Cobelli, M.D.
Istituto Europeo di Oncologia
20141 Milan, Italy
bernardo.rocco@ieo.it
References
Stamey TA, Freiha FS, McNeal JE, Redwine EA, Whittemore AS, Schmid HP. Localized prostate cancer: relationship of tumor volume to clinical significance for treatment of prostate cancer. Cancer 1993;71:Suppl:933-938.
Montironi R, Mazzucchelli R, Scattoni V, Bostwick DG. Pathological finding in TRUS prostatic biopsy — diagnostic, prognostic and therapeutic importance. Eur Urol Suppl 2002;1:60-75.
Hautmann SH, Conrad S, Henke RP, et al. Detection rate of histologically insignificant prostate cancer with systematic sextant biopsies and fine needle aspiration cytology. J Urol 2000;163:1734-1738.
To the Editor: As members of the National Cancer Institute's Cooperative Prostate Cancer Tissue Resource (CPCTR), we read with great interest the findings of Thompson et al. Patients who have prostate cancer with low serum PSA levels are not unusual. A review of the CPCTR database of 4022 patients with prostate cancer who were treated with radical prostatectomy between 1987 and 2003 identified 506 patients with initial PSA levels of less than 4.0 ng per milliliter (12.6 percent), and 155 with values of less than 2.0 ng per milliliter (3.9 percent). Our data indicate that patients whose initial PSA values were less than 4.0 ng per milliliter were younger and had lower Gleason scores, smaller tumors, and lower tumor-recurrence rates (during an average follow-up of 3.8 years) than other patients. It should be noted, however, that roughly 30 percent of patients with cancer who presented with serum PSA levels of less than 2.0 ng per milliliter still had high-grade disease (Gleason score, 7 to 10). These findings demonstrate that clinically annotated tissue resources can be used to corroborate and enhance clinical data sets. CPCTR tissues and data are available to cancer researchers. Additional information can be found on the Web at www.prostatetissues.org.1
Milton W. Datta, M.D.
Jules J. Berman, M.D.
Rajiv Dhir, M.D.
National Cancer Institute
Bethesda, MD 20892
mdatta@mcw.edu
References
Melamed J, Datta MW, Becich MJ, et al. The Cooperative Prostate Cancer Tissue Resource: a specimen and data resource for cancer research. Clin Cancer Res 2004;10:4614-4621.
Peter A. Beatty, M.D.
University of Wisconsin Medical Foundation
Madison, WI 53715
peter.beatty@uwmf.wisc.edu
References
Thompson IA, Pauler DK, Goodman PJ, et al. Prevalence of prostate cancer among men with a prostate-specific antigen level of 4.0 ng per milliliter. N Engl J Med 2004;350:2239-2246.
Barry MJ. Prostate-specific-antigen testing for early diagnosis of prostate cancer. N Engl J Med 2001;344:1373-1377.
Patel A, Dorey F, Franklin J, deKernion JB. Recurrence patterns after radical retropubic prostatectomy: clinical usefulness of prostate specific antigen doubling times and log slope of prostate specific antigen. J Urol 1997;158:1441-1445.
To the Editor: As noted by Thompson et al., a lower PSA threshold for recommending biopsy would allow more prostate cancers to be detected but would also increase the number of unnecessary biopsies. One method of improving the power of the PSA test is to measure free PSA; the higher the fraction of free PSA, the lower the risk of prostate cancer.
The Mayo Clinic guidelines state that when the total PSA level ranges from 2.0 to 3.9 ng per milliliter and free PSA makes up more than 18 percent of the total, the risk of prostate cancer is less than 10 percent. When the total PSA level ranges from 2.0 to 3.9 ng per milliliter and free PSA makes up less than 10 percent of the total, the risk of prostate cancer is more than 30 percent.
I believe that a biopsy should be recommended if the total PSA level is 2.0 ng per milliliter or higher and the fraction of free PSA is less than 10 percent of the total.
Alan I. Glaser, M.D.
Newton-Wellesley Hospital
Newton, MA 02462
md.glal@nwh.org
To the Editor: Thompson et al. show that 15.2 percent of men without clinical risk factors have prostate cancer. However, clinically significant prostate cancer has been defined as a tumor with a volume greater than 0.5 cm3 and a Gleason score greater than or equal to 7.1
In the study by Thompson et al., 67 of 449 men with biopsy-proven prostate cancer (14.9 percent) had high-grade disease; however, a low tumor burden on needle biopsy does not necessarily indicate a low tumor volume or a low stage of cancer.2 Hautmann et al. analyzed 133 cystoprostatectomy specimens from men with PSA levels below 4.0 ng per milliliter; 44 percent had prostate cancer and 12 percent had a tumor volume of 0.5 cm3 or greater.3 Extrapolating these data, about 350 of the 2950 patients in the study of Thompson et al. could be affected by clinically significant prostate cancer.
Bernardo Rocco, M.D.
Deliu Victor Matei, M.D.
Ottavio de Cobelli, M.D.
Istituto Europeo di Oncologia
20141 Milan, Italy
bernardo.rocco@ieo.it
References
Stamey TA, Freiha FS, McNeal JE, Redwine EA, Whittemore AS, Schmid HP. Localized prostate cancer: relationship of tumor volume to clinical significance for treatment of prostate cancer. Cancer 1993;71:Suppl:933-938.
Montironi R, Mazzucchelli R, Scattoni V, Bostwick DG. Pathological finding in TRUS prostatic biopsy — diagnostic, prognostic and therapeutic importance. Eur Urol Suppl 2002;1:60-75.
Hautmann SH, Conrad S, Henke RP, et al. Detection rate of histologically insignificant prostate cancer with systematic sextant biopsies and fine needle aspiration cytology. J Urol 2000;163:1734-1738.
To the Editor: As members of the National Cancer Institute's Cooperative Prostate Cancer Tissue Resource (CPCTR), we read with great interest the findings of Thompson et al. Patients who have prostate cancer with low serum PSA levels are not unusual. A review of the CPCTR database of 4022 patients with prostate cancer who were treated with radical prostatectomy between 1987 and 2003 identified 506 patients with initial PSA levels of less than 4.0 ng per milliliter (12.6 percent), and 155 with values of less than 2.0 ng per milliliter (3.9 percent). Our data indicate that patients whose initial PSA values were less than 4.0 ng per milliliter were younger and had lower Gleason scores, smaller tumors, and lower tumor-recurrence rates (during an average follow-up of 3.8 years) than other patients. It should be noted, however, that roughly 30 percent of patients with cancer who presented with serum PSA levels of less than 2.0 ng per milliliter still had high-grade disease (Gleason score, 7 to 10). These findings demonstrate that clinically annotated tissue resources can be used to corroborate and enhance clinical data sets. CPCTR tissues and data are available to cancer researchers. Additional information can be found on the Web at www.prostatetissues.org.1
Milton W. Datta, M.D.
Jules J. Berman, M.D.
Rajiv Dhir, M.D.
National Cancer Institute
Bethesda, MD 20892
mdatta@mcw.edu
References
Melamed J, Datta MW, Becich MJ, et al. The Cooperative Prostate Cancer Tissue Resource: a specimen and data resource for cancer research. Clin Cancer Res 2004;10:4614-4621.