UroToday - Salvage radiation therapy to the prostatic fossa is often employed in patients with rising PSA after radical prostatectomy (RP). Interestingly, only 25% of men with rising PSA after RP have a positive prostatic fossa biopsy, yet 70% of men with a negative biopsy will have their PSA decline to undetectable levels following salvage external beam radiotherapy. In this study, Pazona and colleagues look at the results of external beam radiotherapy for PSA recurrence in a single surgeon series (William Catalona), examining both 10 year outcome estimates as well as factors that predict response.

Over a 20 year period, 3478 patients underwent RP for clinically localized prostate cancer by Dr. Catalona. Of these, 631 (18%) had evidence of cancer progression after surgery. Of these, 307 patients received local radiation therapy (median dose 63Gy) to the prostatic fossa. Of these, 223 patients had sufficient follow-up data available for analysis. The authors then examined clinical and pathological factors that predicted response to radiation therapy.

The median time from time from RP to PSA recurrence was 23 months (range 1-129). There were 162 (73%) responders to radiation therapy defined as PSA < 0.3 ng/ml after therapy. There was no difference noted with regards to clinical or pathological stage, age at surgery, margin status, or interval between RRP and radiation therapy between responders and non-responders. Gleason 8-10 was more common in non-responders (28% vs. 13%) and the median PSA at start of radiation was higher in non-responders (1.2 ng/ml vs. 0.7 ng/ml, p