Elective Nodal Radiation Therapy in Localized Prostate Cancer: A Meta-Analysis.

PURPOSE: Recently, results from National Surgical Adjuvant Breast and Bowel Project; Radiation Therapy Oncology Group; Gynecologic Oncologic Group (NRG/RTOG) 0924, the largest randomized trial to evaluate the benefit of whole-pelvic radiation therapy (WPRT) in localized prostate cancer, were presented. We conducted an aggregate meta-analysis of all phase III randomized trials to determine the impact of WPRT on oncologic outcomes.

METHODS

PubMed via MEDLINE, clinicaltrials.gov, and conference proceedings were systematically searched for randomized trials of ±WPRT in localized prostate cancer conducted between 1980 and 2025. Random-effects models were used to generate pooled hazard ratios (HRs) with 95% CIs. Heterogeneity was assessed with I2 statistics, and leave-one-out sensitivity analyses were performed. Meta-regression was performed to assess the influence of the proportion of patients with Gleason score 7 to 10, use of androgen deprivation therapy, radiation therapy dose, and field size. Endpoints assessed included overall survival, a biochemical-based endpoint, referred to as biochemical recurrence, and distant metastasis.

RESULTS

Four randomized trials were identified (n = 4465 patients), including 3 multicenter cooperative group trials Urogenital Tumor Study Group-French Association of Urology (GETUG-AFU-01, RTOG 9413, and RTOG 0924) and 1 single-institution trial Prostate-Only versus Whole-Pelvic Radiation Therapy (POP-RT). WPRT did not improve overall survival (HR, 1.05; 95% CI, 0.95-1.16; I2 = 0%), biochemical recurrence (HR, 0.82; 95% CI, 0.63-1.07; I2 = 76%), or distant metastasis (HR, 0.88; 95% CI, 0.58-1.34; I2 = 68%). The high rates of heterogeneity observed were due primarily to the POP-RT trial. In sensitivity analyses, excluding POP-RT heterogeneity was eliminated (HR for biochemical recurrence was 0.91 [95% CI, 0.81-1.02; I2 = 0%]; HR for distant metastasis was 1.06 [95% CI, 0.87-1.29; I2 = 0%]). Meta-regression found no significant modifying effect of any covariables assessed.

CONCLUSIONS

This aggregate meta-analysis did not demonstrate any meaningful benefit of WPRT over prostate-only radiation therapy in unselected localized prostate cancer. Individual patient data meta-analysis is warranted to understand whether any subgroup consistently derives benefit from WPRT.