The role of radiotherapy in pelvic nodal recurrence following definitive treatment for prostate cancer.

Purpose of review: To summarize recent evidence on the role of radiotherapy in managing pelvic lymph node (PLN) recurrence following curative-intent primary therapy for prostate cancer (PCa), focusing on radiotherapy strategies, novel medical imaging, and oncological outcomes.

Recent findings: Prostate-specific membrane antigen PET (PSMA-PET) has improved accuracy of staging in patients with PCa; however, more often than not, it fails to correctly identify PLN metastases, and the impact on clinical outcomes of the patients is uncertain. Metastasis-directed therapies (MDT) combined with short-term androgen-deprivation therapy (ADT) in patients with PLN recurrence are associated with a significantly higher risk of recurrence compared to more comprehensive approaches. Emerging data support the role of elective nodal radiotherapy (ENRT) combined with short-term androgen deprivation therapy (ADT) and radiotherapy boost to the PLN metastases to enhance disease control. Notably, despite treating a more extensive pelvic region than MDT, ENRT does not appear to significantly increase acute toxicity or negatively impact quality of life (QoL). Recent evidence suggests a role for androgen receptor pathway inhibitors (ARPI), such as enzalutamide, in patients with high-risk biochemical recurrence, introducing a new treatment paradigm for patients ineligible for salvage radiotherapy. Ongoing prospective studies are refining the role of radiotherapy in combination with systemic treatments.

Summary: Despite PSMA-PET allowing for improved staging and better patient-tailored decisions, patients with PLN recurrence continue to benefit from comprehensive multimodal treatment approach. Elective PLN irradiation combined with radiotherapy boost and ADT lead to improved disease control, without compromising safety and toxicity. ARPI+ADT and ARPI-monotherapy emerge as alternatives for select patients.