Toxicity in patients receiving adjuvant docetaxel + hormonal treatment after radical radiotherapy for intermediate or high-risk prostate cancer: a preplanned safety report of the SPCG-13 trial

Abstract

Radical radiotherapy (RT) combined with androgen deprivation therapy is currently the standard treatment for elderly patients with localized intermediate- or high-risk prostate cancer (PC). To increase the recurrence-free and overall survival, we conducted an adjuvant, randomized trial using docetaxel (T) in PC patients (Scandinavian Prostate Cancer Group trial 13). The inclusion criteria are the following: men >18 and ≤75 years of age, WHO/ECOG performance status 0--1, histologically proven PC within 12 months before randomization and one of the following: T2, Gleason 7 (4+3), PSA >10; T2, Gleason 8--10, any PSA; or any T3 tumors. Neoadjuvant/adjuvant hormone therapy is mandatory for all patients. The patients were randomized to receive six cycles of T (75 mgm(-2) d 1. cycle 21 d) or no docetaxel after radical RT (with a minimum tumor dose of 74 Gy). This study identifier number is NTC 006653848 (http://www.clinicaltrials.org). In this preplanned safety analysis of 100 patients, T treatment induced grade (G) 3 adverse events (AEs) in 15 patients (30%) and G4 AEs in 30 patients (60%), mainly due to bone marrow toxicity. Neutropenia G3--4 was observed in 72% of the patients, febrile neutropenia was found in 24% of patients, neutropenic infection in 10% of patients and G3 infection without neutropenia in 4% of patients. Nonhematological G3 AEs were rare: anorexia, diarrhea, mucositis, nausea, pain (1 patient each) and fatigue (5). Other severe serious AEs related to T were pulmonary embolism and renal failure. However, only three patients discontinued T before completing the planned six cycles. No deaths had occurred. No patients in the control arm experienced G3--4 toxicities at 12 weeks after the randomization. Adjuvant docetaxel chemotherapy after radiotherapy has a higher frequency of neutropenia than previous studies on patients with metastatic disease. Otherwise, the treatment was quite well tolerated.