Phase II Trial of Radiation Dose Escalation with Conformal External Beam Radiotherapy and high-Dose-Rate Brachytherapy Combined with long-Term Androgen Suppression in Unfavorable Prostate Cancer: Feasibility Report
Jeanette Valero M.D. (1), Mauricio Cambeiro M.D. (1), Carlos Galán M.D. (2), Mercedes Teijeira M.D. (4), Pilar Romero M.D. (5), Marta Moreno M.D. (1), Raquel Ciérvide M.D. (1), José Javier Aristu M.D. (1) and Rafael Martínez-Monge M.D. (1)
(1) Department of Oncology, Clínica Universitaria de Navarra, University of Navarre, Navarre, Spain
(2) Department of Radiation Oncology, Hospital de la Rioja, Logroño, Spain
(3) Department of Urology, Clínica Universitaria de Navarra, University of Navarre, Navarre, Spain
(4) Department of Radiation Oncology, Hospital Divino Vallés, Burgos, Spain
(5)Department of Radiation Oncology, Hospital de Navarra, Pamplona, Spain
To determine the feasibility of combined long-term luteinizing hormone-releasing hormone agonist-based androgen suppressive therapy (AST) and dose escalation with high-dose-rate (HDR) brachytherapy for high-risk (HRPC) or very-high-risk prostate cancer (VHRPC).
METHODS AND MATERIALS
Between January 2001 and October 2006, 134 patients (median age, 70 years) with either National Comprehensive Cancer Network criteria-defined HRPC (n = 47, 35.1%) or VHRPC (n = 87, 64.9%) were prospectively enrolled in this Phase II trial. Tumor characteristics included a median pretreatment prostate-specific antigen level of 14.6 ng/mL, a median clinical stage of T2c, and a median Gleason score of 7. Three-dimensional conformal radiotherapy (54 Gy in 30 fractions) was followed by HDR brachytherapy (19 Gy in 4 b.i.d. treatments). Androgen suppressive therapy started 0-3 months before three-dimensional conformal radiotherapy and continued for 2 years.
One implant was repositioned with a new procedure (0.7%). Five patients (3.7%) discontinued AST at a median of 13 months (range, 6-18 months) because of disease progression (n = 1), hot flashes (n = 2), fatigue (n = 1), and impotence (n = 1). After a median follow-up of 37.4 months (range, 24-90 months), the highest Radiation Therapy Oncology Group-defined late urinary toxicities were Grade 0 in 47.8%, Grade 1 in 38.1%, Grade 2 in 7.5%, and Grade 3 in 6.7% of patients. Maximal late gastrointestinal toxicities were Grade 0 in 73.1%, Grade 1 in 16.4%, Grade 2 in 7.5%, and Grade 3 in 2.9% of patients. There were no Grade 4 or 5 events.
Intermediate-term results show that dose escalation with HDR brachytherapy combined with long-term AST is feasible and has a toxicity profile similar to that reported by previous HDR brachytherapy studies.
CITATION Int J Radiat Oncol Biol Phys. 2010 Feb 1;76(2):386-92