This is very much a cause for concern. After prostatectomy, the PSA should remain undetectable. Any sign of PSA in the blood is an indication of possible cancer recurrence. Possible recurrence sites include the prostate bed, the lymph nodes in the retroperitoneum, and the bone. I would recommend restaging with a CT scan, a bone scan, and possibley even a PET Scan and/or Prostascint scan (with CT correlate). Treatment options in this scenario include hormonal ablation, clinical protocol based therapy (novel therapies being tested for efficacy), or continued observation, although with observation, things will certainly get worse over time (rising PSA, clinical evidence of mets). There is data that hormonal therapy started early in patients with node positive prostate cancer have an improved survival over patients who have hormone therapy started at the time of clinical recurrence. Rarely, radiation may be indicated if the recurrence is localized to the prostate bed, but I think this is unlikely in this case, given that there was seminal vesical and lymph node involvement.

-Christopher Wood, M.D.