Postoperative Intensity Modulated Radiation Therapy in High Risk Prostate Cancer: A Dosimetric Comparison

Digesú, Cinzia; Cilla, Savino; De Gaetano, Andrea; Massaccesi, Mariangela; Macchia, Gabriella; Ippolito, Edy; Deodato, Francesco; Panunzi, Simona; Iapalucci, Chiara; Mattiucci, Gian Carlo; D'Angelo, Elisa; Padula, Gilbert D.A.; Valentini, Vincenzo; Cellini, Numa; Piermattei, Angelo; Morganti, Alessio G.

doi:10.1016/j.meddos.2010.03.009

Next »Medical Dosimetry
Volume 36, Issue 3 , Pages 231-239, Autumn 2011

Postoperative Intensity Modulated Radiation Therapy in High Risk Prostate Cancer: A Dosimetric Comparison

Cinzia Digesú, M.D.
- Department of Radiotherapy, “John Paul II” Center for High Technology Research and Education in Biomedical Sciences, Catholic University, Campobasso
Savino Cilla, M.P.
- Department of Medical Physics, “John Paul II” Center for High Technology Research and Education in Biomedical Sciences, Catholic University, Campobasso
Andrea De Gaetano, M.D.
- CNR–Institute of Systems Analysis and Computer Science (IASI), BioMathLab, Rome
Mariangela Massaccesi, M.D.
- Department of Radiotherapy, “John Paul II” Center for High Technology Research and Education in Biomedical Sciences, Catholic University, Campobasso
Gabriella Macchia, M.D.
- Department of Radiotherapy, “John Paul II” Center for High Technology Research and Education in Biomedical Sciences, Catholic University, Campobasso
- Reprint requests to: Gabriella Macchia, M.D., UO Radioterapia, Centro di Ricerca e Formazione ad Alta Tecnologia nelle Scienze Biomediche “Giovanni Paolo II”, Largo A. Gemelli 1, 86100 Campobasso, Italy
Edy Ippolito, M.D.
- Department of Radiotherapy, “John Paul II” Center for High Technology Research and Education in Biomedical Sciences, Catholic University, Campobasso
Francesco Deodato, M.D.
- Department of Radiotherapy, “John Paul II” Center for High Technology Research and Education in Biomedical Sciences, Catholic University, Campobasso
Simona Panunzi, M.S.
- CNR–Institute of Systems Analysis and Computer Science (IASI), BioMathLab, Rome
Chiara Iapalucci, R.T.
- Department of Radiotherapy, “John Paul II” Center for High Technology Research and Education in Biomedical Sciences, Catholic University, Campobasso
Gian Carlo Mattiucci, M.D.
- Department of Radiotherapy, Policlinico Universitario “A. Gemelli,” Catholic University, Rome
Elisa D'Angelo, M.D.
- Department of Radiotherapy, “John Paul II” Center for High Technology Research and Education in Biomedical Sciences, Catholic University, Campobasso
Gilbert D.A. Padula, M.D.
- Department of Radiation Oncology, The Lacks Cancer Center, Saint Mary's Health Care, Grand Rapids, MI
Vincenzo Valentini, M.D.
- Department of Radiotherapy, Policlinico Universitario “A. Gemelli,” Catholic University, Rome
Numa Cellini, M.D.
- Department of Radiotherapy, Policlinico Universitario “A. Gemelli,” Catholic University, Rome
Angelo Piermattei, M.P.
- Department of Medical Physics, “John Paul II” Center for High Technology Research and Education in Biomedical Sciences, Catholic University, Campobasso
Alessio G. Morganti, M.D.
- Department of Radiotherapy, “John Paul II” Center for High Technology Research and Education in Biomedical Sciences, Catholic University, Campobasso

Received 5 May 2009; accepted 24 March 2010. published online 11 June 2010.

Abstract

The aim of this study was to compare intensity-modulated radiation therapy (IMRT) with 3D conformal technique (3D-CRT), with respect to target coverage and irradiation of organs at risk for high dose postoperative radiotherapy (PORT) of the prostate fossa. 3D-CRT and IMRT treatment plans were compared with respect to dose to the rectum and bladder. The dosimetric comparison was carried out in 15 patients considering 2 different scenarios: (1) exclusive prostate fossa irradiation, and (2) pelvic node irradiation followed by a boost on the prostate fossa. In scenario (1), a 3D-CRT plan (box technique) and an IMRT plan were calculated and compared for each patient. In scenario (2), 3 treatment plans were calculated and compared for each patient: (a) 3D-CRT box technique for both pelvic (prophylactic nodal irradiation) and prostate fossa irradiation (3D-CRT only); (b) 3D-CRT box technique for pelvic irradiation followed by an IMRT boost to the prostatic fossa (hybrid 3D-CRT and IMRT); and (c) IMRT for both pelvic and prostate fossa irradiation (IMRT only). For exclusive prostate fossa irradiation, IMRT significantly reduced the dose to the rectum (lower Dmean, V50%, V75%, V90%, V100%, EUD, and NTCP) and the bladder (lower Dmean, V50%, V90%, EUD and NTCP). When prophylactic irradiation of the pelvis was also considered, plan C (IMRT only) performed better than plan B (hybrid 3D-CRT and IMRT) as respect to both rectum and bladder irradiation (reduction of Dmean, V50%, V75%, V90%, equivalent uniform dose [EUD], and normal tissue complication probability [NTCP]). Plan (b) (hybrid 3D-CRT and IMRT) performed better than plan (a) (3D-CRT only) with respect to dose to the rectum (lower Dmean, V75%, V90%, V100%, EUD, and NTCP) and the bladder (Dmean, EUD, and NTCP). Postoperative IMRT in prostate cancer significantly reduces rectum and bladder irradiation compared with 3D-CRT.

Key words: Prostate cancer, Postoperative therapy, IMRT, Radical prostatectomy