Work

Harnessing the synergy of contact brachytherapy and immune checkpoint inhibitors in advanced melanoma: first reported case series

Year: 2025

Type: article

Abstract: Background: Melanoma is an aggressive malignancy with high metastatic potential, often requiring systemic treatment with immune checkpoint inhibitors (CHI) in advanced stages. While CHI has significantly improved outcomes, its combination with local radiotherapy - particularly brachytherapy (BT) - may further enhance therapeutic efficacy by promoting immunogenic tumor cell death. BT enables precise delivery of high radiation doses, providing rapid symptom relief and potentially triggering local and systemic immune responses. This case series presents the first known clinical experience with noninvasive contact high-dose-rate brachytherapy (HDR-BT) combined with CHI in patients with metastatic melanoma treated in a palliative setting. Materials and methods: We retrospectively analyzed four patients with stage IV melanoma and symptomatic subcutaneous metastases, all receiving ongoing CHI (nivolumab or pembrolizumab). Each underwent a single HDR-BT session (5-7 Gy) using a Freiburg Flap applicator. The primary goal was symptom relief. Treatment response was assessed clinically and radiologically, focusing on local control, response of non-irradiated lesions, progression-free survival (PFS), and overall survival (OS). Results: All patients experienced rapid clinical improvement and significant regression of the irradiated lesion, with minimal (Grade 0-1) acute skin toxicity. In two cases, complete remission of treated sites was achieved. One patient demonstrated long-term remission in both subcutaneous and visceral metastases. Median PFS was 3.4 months (range: 1.5-15.0), and OS ranged from 8.5 to 22 months. Conclusions: Single-fraction contact HDR-BT in combination with CHI appears to be a safe and effective palliative strategy for metastatic melanoma, offering fast local control, minimal toxicity, and potential systemic immune benefits.

Source: Reports of Practical Oncology & Radiotherapy

DOI: 10.5603/rpor.108661

Authors: Artur Jan Chyrek, Łukasz Galus, Jacek Mackiewicz, Adam Kluska, Wojciech Maria Burchardt, Adam Chicheł

Institutions: Poznan University of Medical Sciences, Greater Poland Cancer Center

Language: English

Topic: Cancer Immunotherapy and Biomarkers

Subfield: Oncology

Field: Medicine

Domain: Health Sciences

SDG: Good health and well-being

Open Access status: gold

Estimated APC paid: $1,713