Efficacy of High-dose Palliative Radiotherapy for Localised, Castration-resistant Prostate Cancer

Local Prostate Radiation Therapy and Symptomatic Local Events in De Novo Metastatic Prostate Cancer

PURPOSE

Local prostate radiation therapy (LPRT) for low-burden metastatic prostate cancer (mPCa) improves overall survival and is the standard of care. The role of LPRT in reducing symptomatic local events (SLE) remains unclear. We aimed to identify SLE risk factors and to evaluate the association between LPRT and SLE in mPCa.

METHODS AND MATERIALS

We conducted a retrospective, population-based cohort study of patients initially diagnosed with mPCa between 2005 and 2016 in a cancer registry. Patient, tumor, and treatment characteristics were obtained from chart review and the cancer registry. The coprimary endpoints were genitourinary (GU) and gastrointestinal (GI) SLE, identified by physician billing claims between 2004 and 2017 for diagnostic or therapeutic procedures potentially related to GU and GI SLE. The effect of LPRT on SLE was evaluated using both recurrent event (Andersen-Gill model) and time-to-first-event sequential landmark analyses. Risk factors for SLE were assessed by multivariable Cox regression. LPRT was defined as ≥40 Gy within 1 year of diagnosis. Metastatic burden was defined per the STAMPEDE trial.

RESULTS

Of 1363 patients, 46 (3.4%) received LPRT. Median follow-up was 27.3 and 28.9 months in the control and LPRT groups, respectively. LPRT was associated with less recurrent GU SLE (hazard ratio [HR], 0.34; 95% confidence interval [CI], 0.17-0.67; P = .002), upper tract obstruction (HR, 0.20; 95% CI, 0.05-0.84; P = .03), and cystoscopy (HR, 0.38; 95% CI, 0.15-0.96; P = .04). Metastatic burden was not associated with SLE.

CONCLUSIONS

LPRT in mPCa was associated with less recurrent GU SLE, specifically for upper tract obstruction and cystoscopy.

Hong Kong Urological Association-Hong Kong Society of Uro-Oncology consensus statements on the management of advanced prostate cancer-2019 Updates

BACKGROUND

To update the Hong Kong Urological Association-Hong Kong Society of Uro-Oncology consensus statements on the management of advanced prostate cancer, the same panelists as in the previous consensus panel held a series of meetings to discuss updated clinical evidence and experiences.

METHODS

The previous consensus statements were retained, deleted, or revised, and new statements were added. At the final meeting, all statements were reviewed and amended as appropriate, followed by panel voting.

RESULTS

There were significant changes and additions to the previous consensus statements, primarily driven by the advances in androgen receptor signaling inhibitors, treatment sequencing in metastatic castration-resistant prostate cancer, and increasing recognition of oligometastatic prostate cancer since the introduction of prostate-specific membrane antigen positron emission tomography. In this update, a total of 59 consensus statements were accepted and established.

CONCLUSIONS

The consensus panel updated consensus statements on the management of advanced prostate cancer, aiming to allow physicians in the region to keep abreast of the recent evidence on optimal clinical practices.

Successful management of prostate cancer with bulky pelvic lymph node metastases after rapid development of castration-resistant prostate cancer: a case report with review of the literature

The rapid development of castration-resistant prostate cancer (CRPC) is a poor prognostic sign for loco-regionally advanced prostate cancer. Non-metastatic CRPC (nmCRPC) with bulky regional lymph node metastases is extremely rare and difficult to treat clinically without reported case. We present a case of a 72-year-old man with locally advanced prostate cancer with bulky lymph node metastases (53 mm × 77 mm × 67 mm), developing nmCRPC after 9-month ADT treatment. Immunohistochemistry (IHC) tests found partially positive MUC1 and negative BRCA1 expression in the initial biopsy specimens. Next-generation sequence analysis on the blood specimen after CRPC predicted a good tolerance to docetaxel. According to the multidisciplinary team recommendations, he was administrated docetaxel 75 mg/m² on day 1 every 21 days for 6 cycles, and subsequently radiotherapy, with the delivery of a total dose of 67.5, 60-65 and 47.5 Gy in 25 fractions to the prostate, the enlarged lymph nodes and the whole pelvis respectively. Over a follow-up of 50 months, his disease has achieved good local control and he is alive without evidence of distant metastases or late adverse events. This case highlights individualized and multimodal therapy of intensification of systemic therapy and timely application of radiotherapy in such rare condition.

Safety and Feasibility of Radiation Therapy to the Primary Tumor in Patients With Metastatic Castration-resistant Prostate Cancer

INTRODUCTION

The objective of this study was to evaluate the safety and feasibility of radiation therapy (RT) to the primary tumor in patients with metastatic castration-resistant prostate cancer (mCRPC).

PATIENTS AND METHODS

This retrospective study included 105 patients with mCRPC who were treated between April 2004 and May 2019. We divided the patients into 2 groups: patients treated with RT to the primary tumor after they developed CRPC (RT group) and without (non-RT group). The primary purpose was safety assessed using the Common Terminology Criteria for Adverse Events. The secondary purpose included prostate-specific antigen (PSA) response, cancer-specific survival (CSS), and overall survival (OS). Background-adjusted multivariate analyses, with the inverse probability of treatment weighting (IPTW) method, were performed to evaluate impact of RT on CSS and OS.

RESULTS

The median age at CRPC diagnosis was 75 years, and the median follow-up period after CRPC diagnosis was 21 months. The adverse events rates related to RT in any grade and grade ≥ 3 were 55% and 23%, respectively. Nine (29%) patients achieved ≥ 30% PSA decline with RT. In multivariate analyses with the IPTW method, the CSS and OS in the RT group were significantly longer than those in the non-RT group. In subgroup analyses with the IPTW method, RT was significantly associated with improved OS in patients aged ≥ 75 years and patients with initial PSA ≥ 500 ng/mL, cT4, Gleason score ≥ 8, and high-volume metastatic burden.

CONCLUSIONS

RT to the primary tumor is safe and feasible, and it has potential benefits on oncologic outcomes in patients with mCRPC.

Consensus on management of castration-resistant prostate cancer on behalf of the Urological Tumours Working Group (URONCOR) of the Spanish Society of Radiation Oncology

BACKGROUND

The knowledge in the field of castration-resistant prostate cancer (CRPC) is developing rapidly, with emerging new therapies and advances in imaging. Nonetheless, in multiple areas there is still a lack of or very limited evidence, and clear guidance from clinicians regarding optimal strategy is required.

METHODS

A modified Delphi method, with 116 relevant questions divided into 7 different CRPC management topics, was used to develop a consensus statement by the URONCOR group.

RESULTS

A strong consensus or unanimity was reached on 93% of the proposed questions. The seven topics addressed were: CRPC definition, symptomatic patients, diagnosis of metastasis, CRPC progression, M0 management, M1 management and sequencing therapy, and treatment monitoring.

CONCLUSIONS

The recommendations based on the radiation oncology experts' opinions are intended to provide cancer specialists with expert guidance and to standardise CRPC patient management in Spain, facilitating decision-making in different clinically relevant issues regarding CRPC patients.

Loco-regional treatment for castration-resistant prostate cancer: Is there any rationale? A critical review from the AFU-GETUG

Emerging evidence from population-based and retrospective series suggests a potential improvement of clinical outcomes in metastatic prostate cancer. Moreover, metastasis-directed treatment has shown encouraging results in this setting. There is an increasing interest in exploring the potential of local therapies in advanced prostate cancer, but this has rarely been specifically addressed in the castration-resistant state, whether non-metastatic or metastatic. A review of relevant articles was performed on the oncologic benefit of local treatment of the primary tumor or metastasis-targeted treatment in castration-resistant prostate cancer patients. The main goal of this strategy is to delay introduction of a new systemic agent to maintain quality of life and potentially to limit resistance. Further investigation is required to provide high-level evidence for the oncologic benefit of this treatment modality.

External beam radiation for the treatment of castration-resistant prostate cancer following primary hormonal therapy with androgen ablation: Analysis and outcome of 21 patients

Patients who undergo early androgen-deprivation therapy for prostate cancer may eventually develop castration-resistant prostate cancer. However, no optimal treatment for non-metastasized castration-resistant prostate cancer has yet been established. In the present retrospective, single-institutional study, the radiotherapy (RT) outcomes were evaluated in patients who underwent androgen-deprivation therapy for non-metastatic prostate cancer and subsequently developed castration-resistant disease. Following a thorough chart review, the data of 21 patients with castration-resistant prostate cancer who were treated between 2000 and 2010 with external beam radiation therapy (EBRT) at a prostate radiation dose of >45 Gy were evaluated. Of the 21 patients, 16 (76%) developed biochemical recurrence after RT, with a mean time to biochemical recurrence of 17 months. A total of 18 patients succumbed to the disease during follow-up, with a mean survival of 3 years after RT. A radiation dose of >66 Gy was associated with a longer time to biochemical recurrence after RT (P=0.011) and a longer survival, compared with a dose of ≤66 Gy (P=0.028). The mean overall survival time after RT was 42 months and did not depend on the primary hormonal treatment. Prostate-specific survival time was negatively associated with the Gleason score at diagnosis. The prostate-specific antigen (PSA) concentration prior to RT was a prognostic factor for biochemical recurrence of prostate cancer after RT, as well as for prostate cancer-specific survival. Finally, the multivariate analysis revealed that age, PSA concentration prior to RT and a high Gleason score were independent prognostic factors for prostate cancer-specific survival. Overall, our study findings demonstrated that disease progression was common after EBRT for castration-resistant prostate cancer and that survival was limited. However, young patients and those with low-risk disease at the time of diagnosis may benefit from RT.