Electrochemotherapy for Breast Cancer

Skin metastases occur more commonly in breast cancer (BC) than in any other malignancy in women, exceeding 20 % of all cutaneous metastases. They most commonly present on the chest wall (CW), but the abdomen, back, scalp, and upper extremities also are sites of occurrence. Presentation may be ambiguous; nevertheless, their local progression may lead to extensive CW infiltration or fungating masses, with associated symptoms (e.g., bleeding, oozing, smell) and severe patient discomfort. Since cutaneous metastases portends an incurable diagnosis, the use of locoregional treatment focuses on preventing uncontrolled tumor spread, palliating symptoms, and preserving QoL. The first clinical experiences with electrochemotherapy in BC date back to the 1990s and indicated an objective response rate up to 90 %, with 59 % of subjects achieving local complete remission. More recently, following the standardization of the procedure, thanks to the adoption of the European Standard Operating Procedures of Electrochemotherapy (ESOPE) in 2006, sustained complete response rates (range, 26–58 %) have been confirmed, with durable CW control. Due to its mainly dermatologic toxicity profile, the treatment can be safely repeated, the principal concerns being pain control and lung toxicity, particularly when maximum cumulative exposure to bleomycin is reached. Early patient referral and advanced wound management are crucial aspects for ensuring patient comfort after electrochemotherapy. The most recently published experience, based on the retrospective analysis of 125 patients, indicates a 58 % complete response rate, with 86 % 1-year local progression-free survival. In this study, small tumor size, hormone receptor positivity, low proliferative index, and absence of visceral metastases were predictors of response. Electrochemotherapy represents an efficacious treatment modality for cutaneous metastases and holds promise in the management of patients with metastatic as well as locoregional (skin-only recurrence) BC. Future well-designed clinical trials will clarify the role of electrochemotherapy in BC and explore its rational combination with systemic agents.