Re-treatment with radium-223: first experience from an international, open-label, phase I/II study in patients with castration-resistant prostate cancer and bone metastases.

BACKGROUND: Six radium-223 injections at 4-week intervals is indicated for patients with castration-resistant prostate cancer and symptomatic bone metastases. However, patients usually develop disease progression after initial treatment. This prospective phase I/II study assessed re-treatment safety and efficacy of up to six additional radium-223 injections. PATIENTS AND METHODS: Patients had castration-resistant prostate cancer and bone metastases and six initial radium-223 injections with no on-treatment bone progression; all had subsequent radiologic or clinical progression. Concomitant agents were allowed at investigator discretion, excluding chemotherapy and initiation of new abiraterone or enzalutamide. The primary endpoint was safety; additional exploratory endpoints included time to radiographic bone progression, time to total alkaline phosphatase and prostate-specific antigen progression, radiographic progression-free survival, overall survival, time to first symptomatic skeletal event (SSE), SSE-free survival, and time to pain progression. RESULTS: Among 44 patients, 29 (66%) received all six re-treatment injections. Median time from end of initial radium-223 treatment was 6 months. Forty-one (93%) reported ≥1 treatment-emergent adverse event. No grade 4-5 hematologic treatment-emergent adverse events occurred. Only one (2%) patient had radiographic bone progression; eight (18%) had radiographic soft tissue tumor progression (three lymph node and five visceral metastases). Median times to total alkaline phosphatase and prostate-specific antigen progression were not reached and 2.2 months, respectively. Median radiographic progression-free survival was 9.9 months (12.8-month maximum follow-up). Five (11%) patients died and eight (18%) experienced first SSEs. Median overall survival, time to first SSE, and SSE-free survival were not reached. Five (14%) of 36 evaluable patients (baseline worst pain score ≤7) had pain progression. After 2 years of follow-up, 28 (64%) patients died, and the median overall survival was 24.4 months. CONCLUSIONS: Re-treatment with a second course of six radium-223 injections after disease progression is well tolerated, with minimal hematologic toxicity and low radiographic bone progression rates in this small study with limited follow-up. Favorable safety and early effects on disease progression indicate that radium-223 re-treatment is feasible and warrants further evaluation in larger prospective trials.

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.

BACKGROUND: 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). METHODS: 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). RESULTS: 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. CONCLUSIONS: 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.

Association between the presence of bacterial 16S RNA in prostate specimens taken during transurethral resection of prostate and subsequent risk of prostate cancer (Sweden).

OBJECTIVE: To study bacterial 16S RNA in archival prostate samples from 352 patients with benign prostate hyperplasia (BPH) and evaluate whether the presence of bacterial DNA was different in those who later developed prostate cancer (n = 171) and in the matched controls that did not progress to cancer (n = 181). METHODS: 16S DNA PCR followed by cloning and sequencing the positive samples. RESULTS: In 96/352 (27%) of the prostate tissue specimens 16S RNA were detected. Sequence analysis revealed Propionibacterium acnes as the predominant microorganism (23% of 16S RNA positive patients). The second most frequent isolate-Escherichia coli was found in 12 (12%) patients. The other isolates included Pseudomonas sp. (3 patients), Actinomyces sp. (2), Streptococcus mutans (1), Corynebacterium sp. (2), Nocardioides sp. (1), Rhodococcus sp. (1) Veillonella sp. (2). In P. acnes positive samples 62% exhibited severe histological inflammation versus 50% in the bacteria-negative group (p = 0.602). The presence of P. acnes in the prostate was associated with prostate cancer development (OR 2.17, 95% CI 0.77-6.95). CONCLUSIONS: This study has revealed P. acnes as the most common bacteria in the prostate in BPH. Further studies are needed to clarify its role in contributing to the development of prostatic inflammation and prostate cancer.