Favorable outcome of intraoperative radiotherapy to the primary site in patients with metastatic prostate cancer

Radiation therapy to the primary in metastatic prostate cancer: palliation only or altering tumor biology?

PURPOSE OF REVIEW

Despite improvement in systemic treatment, the prognosis of men with de novo metastatic prostate cancer remains poor. Treating the local disease may not only reduce the occurrence of local urologic symptoms, but also slow the metastatic process, either by reducing the seeding from the primary tumor or by altering the microenvironment and thus minimizing the formation of new metastatic sites.

RECENT FINDINGS

Retrospective and population-based studies have suggested that the addition of local treatment to systemic therapy may improve survival in this patient group. The aim of this review is to discuss the biologic rationale of such an approach, present and discuss the current available evidence, with a focus on radiation-based treatments. It is key to also address the issue of patient selection as not all patients with metastatic prostate cancer will benefit from the treatment of the primary tumor.

SUMMARY

Retrospective and population-based research suggests a survival benefit of prostatectomy or radiotherapy in metastatic prostate cancer patients. Clinical trials evaluating the role of prostate radiotherapy in the metastatic setting are ongoing.

Low TIM3 expression indicates poor prognosis of metastatic prostate cancer and acts as an independent predictor of castration resistant status

T cell immunoglobulin 3 (TIM3) is a cell surface star molecule expressed on T cells, and also marks dysfunctional CD8⁺ T cells in various kinds of cancers. However, there are few studies focusing on the expression of TIM3 in tumor cells. In our study, we recruited 139 patients with metastatic prostate cancer (mPCa) who received transurethral resection of the prostate (TURP) consecutively to examine whether TIM3 expression level is associated with overall survival (OS) in mPCa patients. Immunohistochemistry was performed to determine TIM3 expression in prostate cancer tissues and then patients were divided into two groups. In multivariate Cox analysis, we revealed that mPCa patients with negative TIM3 expression, younger age, no radiotherapy, higher Gleason score, higher cT stage and patients of mCRPC had a shorter OS. Therefore, a predictive nomogram was generated with identified independent prognostic factors to assess patients’ OS at 3 years. Multivariate logistic regression revealed that higher cT stage, higher Gleason score and low TIM3 expression were independent predictors of metastatic castration resistant prostate cancer (mCRPC). In conclusion, low expression level of TIM3 in prostate cancer tissues is an independent prognostic factor of poor prognosis for mPCa patients, and also an independent predictor of mCRPC.