For men with prostate cancer, treatment with irradiation is associated with lasting prostate cancer control, with no recurrence seen from 15.5 to 25 years, according to a study.
Frank A. Critz, MD, of the Radiotherapy Clinics of Georgia in Atlanta, and colleagues followed 3,546 consecutive hormone-naive men, treated with irradiation for prostate cancer (retropubic and later transperineal, followed by external beam radiation), from 1984 to 2000 (median follow-up, 11 years) to examine whether control of prostate cancer is durable.
The disease-free survival rate was 75% at 10 years and remained stable at 73% at 15, 20, and 25 years, Dr. Critz’s group reported in The Journal of Urology (2013;189:878-883). The longest time to recurrence was 15.5 years. Late recurrence, defined as recurrence after 10-year follow-up, occurred in 5% of the 313 men with recurrences who were treated 16 to 25 years earlier. The 15-year disease-free survival rate was 79% for men implanted by the transperineal method since 1995.
“With this irradiation program, cancer control, defined using the recurrence definition for radical prostatectomy, was durable with no further recurrence between 15.5 and 25 years of follow-up,” the researchers wrote. “This study also suggests that at least 15 years of follow-up are necessary to fully evaluate any prostate cancer treatment.”
The investigators defined as cancer control as a PSA cutoff of less than 0.2 ng/mL.