To retrospectively assess outcomes and to identify prognostic factors in patients diagnosed with intermediate-risk (IR) prostate cancer (PCa) treated with primary external beam radiotherapy (EBRT).
Data were obtained from the multi-institutional Spanish RECAP database, a population-based prostate cancer registry in Spain. All IR patients (NCCN criteria) who underwent primary EBRT were included. The following variables were assessed: age; prostate-specific antigen (PSA); Gleason score; clinical T stage; percentage of positive biopsy cores (PPBC); androgen deprivation therapy (ADT); and radiotherapy dose. The patients were stratified into one of three risk subcategories: (1) favourable IR (FIR; GS 6, ≤ T2b or GS 3 + 4, ≤ T1c), (2) marginal IR (MIR; GS 3 + 4, T2a-b), and (3) unfavourable IR (UIR; GS 4 + 3 or T2c). Biochemical relapse-free survival (BRFS), disease-free survival (DFS), cancer-specific survival (CSS), and overall survival (OS) were assessed.
A total of 1754 patients from the RECAP database were included and stratified by risk group: FIR, n = 781 (44.5%); MIR, n = 252 (14.4%); and UIR, n = 721 (41.1%). Mean age was 71 years (range 47-86). Mean PSA was 10.4 ng/ml (range 6-20). The median radiotherapy dose was 74 Gy, with mean doses of 72.5 Gy (FIR), 73.4 Gy (MIR), and 72.8 Gy (UIR). Most patients (88%) received ADT for a median of 7.1 months. By risk group (FIR, MIR, UIR), ADT rates were, respectively, 88.9, 86.5, and 86.9%. Only patients with ≥ 24 months of follow-up post-EBRT were included in the survival analysis (n = 1294). At a median follow-up of 52 months (range 24-173), respective 5- and 10-year outcomes were: OS 93.6% and 79%; BRFS 88.9% and 71.4%; DFS 96.1% and 89%; CSS 98.9% and 94.6%. Complication rates (≥ grade 3) were: acute genitourinary (GU) 2%; late GU 1%; acute gastrointestinal (GI) 2%; late GI 1%. There was no significant association between risk group and BRFS or OS. However, patients with favourable-risk disease had significantly better 5- and 10-year DFS than patients with UIR: 98.7% vs. 92.4% and 92% vs. 85.8% (p = 0.0005). CSS was significantly higher (p = 0.0057) in the FIR group at 5 (99.7% vs. 97.3%) and 10 years (96.1% vs. 93.4%). On the multivariate analyses, the following were significant predictors of survival: ADT (BRFS and DFS); dose ≥ 74 Gy (BRFS); age (OS).
This is the first nationwide study in Spain to report long-term outcomes of patients with intermediate-risk PCa treated with EBRT. Survival outcomes were good, with a low incidence of both acute and late toxicity. Patients with unfavourable risk characteristics had significantly lower 5- and 10-year disease-free survival rates. ADT and radiotherapy dose ≥ 74 Gy were both significant predictors of treatment outcomes.
Clinical & translational oncology : official publication of the Federation of Spanish Oncology Societies and of the National Cancer Institute of Mexico. 2018 Dec 10 [Epub ahead of print]
A Hervás, J Pastor, C González, J Jové, A Gómez, M Casaña, E Villafranca, J L Mengual, V Muñoz, I Henriquez, J Muñoz, E Collado, J Clemente
Department of Radiation Oncology, Hospital Ramón y Cajal, Madrid, Spain. ., Department of Radiation Oncology, Hospital General de Valencia, Valencia, Spain., Department of Radiation Oncology, Hospital Gregorio Marañón, Madrid, Spain., Department of Radiation Oncology, Hospital Germans Trias i Pujol, Barcelona, Spain., Department of Radiation Oncology, Hospital Clínico Universitario, Santiago de Compostela, Spain., Department of Radiation Oncology, Instituto Valenciano de Oncologia, Valencia, Spain., Department of Radiation Oncology, Hospital Clínico Universitario, Pamplona, Spain., Department of Radiation Oncology, Hospital do Mixoeiro, Vigo, Spain., Department of Radiation Oncology, Hospital Universitario Sant Joan, Reus, Spain., Department of Radiation Oncology, Hospital Infanta Cristina, Badajoz, Spain., Department of Radiation Oncology, Hospital Uiversitario La Fe, Valencia, Spain., Department of Radiation Oncology, Instituto Valenciano de Oncologia, Alcoy, Spain.