Dose Escalated Pelvic Radiotherapy for Prostate Cancer in Definitive or Postoperative Setting

Management of clinically node positive (cN+) prostate cancer represents a debated issue, both in the definitive and postoperative settings. Once macroscopic evidence of pelvic nodal disease is detected, loco-regional treatment should be performed, but standard approach has yet to be defined. Moreover, this problem is currently stressed by the availability of newer imaging methods (e.g Choline or PSMA PET/CT) and modern intensity modulated radiotherapy. Indeed, patients with detectable pelvic disease are increasing thanks to modern imaging if compared to standard staging (e.g CT or bone scan), and the possibility to administer dose escalated treatments on macroscopic disease prompts the development of tailored therapeutic strategies.

We performed a national study collecting data from six different Italian institutes treating cN+ patients with prophylactic pelvic irradiation and boost on pathologic pelvic lymph nodes detected with CT, MRI, or choline PET/CT. Both patients undergoing definitive and postoperative treatment were included in the present analysis. Either prostate and seminal vesicles or prostate bed were treated according to these different settings.

Our data showed excellent results in terms of biochemical relapse free and overall survival. Interestingly, receiving higher dose to positive pelvic nodes was associated with improved outcomes, underlining that dose escalated radiotherapy may obtain high cure rate in this poor prognosis population. Conversely, upfront surgical approach did not improve biochemical relapse-free survival. Thus, upfront radical prostatectomy may expose patients to unnecessary toxicity of multi-modal approaches (e.g surgery followed by postoperative radiotherapy on prostate bed and whole pelvis). Taken together, these observations suggest that upfront definitive radiotherapy may be the optimal approach for advanced disease, and intensity modulated techniques with adequate dose to positive pelvic nodes should be administered.

Written by: Giulio Francolini, MD, Radiation Oncology Unit, University of Florence, Italy

Read the Abstract

Login