The May 20 issue of the Journal of Clinical Oncology includes the results of a review attempting to identify which characteristics predict successful treatment with salvage radiotherapy for recurrent prostate cancer after radical prostatectomy. While a rising, detectable PSA after radical prostatectomy is undoubtedly associated with recurrent cancer determining whether the patient has a local or systemic relapse remains a challenge.

Despite attempts at localizing the disease with studies such as the Prostascint scan, bone scan, MRI, or transrectal biopsies of the vesicourethral anastomosis, currently no reliable methods exist to determine whether the patient has developed a local or systemic recurrence. Having a prognostic nomogram to predict response to radiotherapy would facilitate decision-making in the patient with a recurrence after radical prostatectomy.

In the May 20 issue of the Journal of Clinical Oncology, Stephenson and colleagues reported the results of a multi-institutional review attempting to identify which characteristics predict successful treatment with salvage radiotherapy for recurrent prostate cancer after radical prostatectomy. A nomogram was presented to predict the probability of cancer control 6 years after salvage radiotherapy.

A cohort of 1,540 men who received salvage radiotherapy for recurrence after radical prostatectomy was identified from 17 medical centers. PSA recurrence after prostatectomy was defined as a serum PSA of 0.2 ng/ml and rising or a single PSA of 0.5 ng/ml or greater. The variables included in the Cox regression analysis were pre-prostatectomy PSA, Gleason score, extracapsular extension, seminal vesicle invasion, surgical margins, lymph node status, persistently elevated PSA post-RRP, pre-radiotherapy PSA, PSA doubling time, neoadjuvant androgen deprivation and radiation dose.

The probability of remaining free of disease after 6 years was 32 per cent for the entire cohort (95 per cent CI, 28 per cent to 35 per cent), which improved to 48 per cent for patients who received their radiotherapy before their PSA reached 0.6 ng/ml. The most important variables in the model were the serum PSA level before radiotherapy, surgical margin status, use of androgen deprivation before or during radiotherapy and the presence of lymph node metastasis.

This retrospective study with a large cohort of patients treated with salvage radiotherapy after prostatectomy suggests that up to 50 per cent of patients may remain free of disease six years after treatment if it is instituted before their serum PSA rises above 0.5 ng/ml. The nomogram proposed predicts with reasonable accuracy which patients are more likely to exhibit a favorable response to salvage radiotherapy and may aid in clinical decision-making.

Stephenson AJ, Scardino PT, Kattan MW, Pisansky TM, Slawin KM, Klein EA, Anscher MS, Michalski JM, Sandler HM, Lin DW, Forman JD, Zelefsky MJ, Kestin LL, Roehrborn CG, Catton CN, DeWeese TL, Liauw SL, Valicenti RK, Kuban DA, Pollack A.

J Clin Oncol. 25(15):2035-41 May 20, 2007
doi: 10.1200/JCO.2006.08.9607