Analysis of independent variables affecting survival after recurrence of prostate cancer

Two hundred and sixty-six patients developed recurrence after external beam radiation therapy for Stage B or C prostate cancer. The median survival from the time of recurrence was 30 months, the 5-year actuarial survival was 22% and the 8-year actuarial survival was 13%. The original stage influences survival after recurrence. Median survival is 35 months for Stage B and 27 months for Stage C. Five-year actuarial survivals are 31% for Stage B and 16% for Stage C. The site of recurrence (infield or metastatic) influences survival after recurrence. Median survival is 33 months for infield and 25 months for metastatic. Five-year actuarial survival is 30% for infield and 17% for metastatic. The time of recurrence influences survival after recurrence, comparing survival in patients recurring in the first year after treatment, to patients recurring in the second or later years after treatment. Median survival after recurrence is 14 months for those who recur in the first year, 32 months for those who recur later. Histologic grade influences survival after recurrence. Median survivals are 49 months for well differentiated, 31 months for moderately differentiated, and 23 months for poorly differentiated. Cox regression analysis indicates that original stage, site of recurrence (local vs. metastatic), time of recurrence after therapy, and histologic grade are all independent variables influencing survival after recurrence (p = less than .01). This study supports the aggressive treatment of prostate cancer to prevent recurrence and provides a means of estimating prognosis for patients who suffer a recurrence of their prostate cancer after treatment.