I read with interest the article by Hanks and colleaguesand the reviews that followedon the evidence for cure in prostate cancer. The data were encouraging, and the concepts raised were stimulating. Any discussion of tumor control and patient cure in prostate cancer inevitably refers to prostate-specific antigen (PSA) control. The 5-, 10-, and 15-year posttreatment PSA level is worthy of debate.
In discussing cure in prostate cancer patients, the minimum definition should be clinical control at the time of death. The maximum designation would be PSA control at death. Not many clinicians and patients are interested in the risk of cancer failure after death. This is important because 40% to 60% of men will die of non-cancer-related causes in the 10 to 15 years following treatment of prostate cancer. The article does not report mortality from prostate cancer following external radiation. The surgical literature suggests that the average time to cancer death after PSA failure is 13 to 15 years.
PSA and Local TreatmentAnother point of interest centers on the risk of PSA failure more than 3 years after treatment. PSA relapse is reduced with appropriate local treatmenteg, prostatectomy, two-dimensional radiation therapy, three-dimensional conformal radiation therapy, dose escalation, intensity-modulated radiation therapy, implant, or a combination of these approaches. PSA failures related to local relapse (and late metastases) may benefit from more aggressive local treatment. However, a major cause of PSA failure is related to metastatic disease already present at the time of local treatment. Hence, the rate of PSA failure may be related to patient and tumor selection rather than the effectiveness of the local treatment.
GILBERT LAWRENCE, MD, DMRT, FRCR
Regional Cancer Center, Radiation Oncology,
Faxton-St. Luke’s Healthcare, Utica, New York