Electrochemotherapy, cutaneous metastases, breast cancer, palliative care, bleomycin.
Cutaneous recurrence from breast cancer represents a clinical challenge for breast surgeons and oncologists. The pattern of recurrence varies from skin-only metastases to wide-spread and distant disease. Patients complain of itch, bleeding, oozing, disfigurement, and pain. This can have a profound impact on their quality of life, and serves as an unwanted reminder that their disease is active and possibly out of control. Treatment of cutaneous metastases could reduce or eliminate these symptoms and improve quality of life. Electrochemotherapy is a recognised palliative treatment for cutaneous metastases. Electrical pulses delivered to the tumour potentiate the action of cytotoxic drugs within the tumour, resulting in tumour regression.
Our unit has treated patients with cutaneous metastases since 2009. In total the 200 patients have been treated with ECT, or which 39 were patients with breast cancer. Referrals patterns varied from local oncology MDTs, to self-referrals. As a member of InspECT (International Network for Sharing Practice on ElectroChemoTherapy), all patient data was collected and uploaded to a shared database with patients consent. Patients received either intratumoral injection (1000 IU/ml) or systemic infusion (15,000 IU/m2) of bleomycin, under general anaesthesia, depending on tumour size. Electrical pulses were sequentially applied to the tumour area, using an electroporation system with needle or plate electrodes (IGEA, Italy).
Between 2009 and 2017 39 patients with cutaneous breast cancer were treated at our institution. The median age was 65 years, and patients had previously received chemotherapy, radiotherapy, endocrine therapy and HER2 targeted therapy. The main treated area was the chest, and this varied from single subcentimetre nodules, to the entire chest wall. Response to treatment was assessed weekly for four weeks, at week 8, and at later time-points if required. Response varied from complete response (eradication of pre-treatment disease), to no response, and to subsequent disease progression. Most patients had only a single treatment with ECT. Common side effects were ulceration, long-lasting hyperpigmentation, and low grade pain. No serious adverse events were observed.
At St George’s Hospital we have treated many patients since 2009 and have contributed significantly to the InspECT database. Electrochemotherapy is a useful treatment for local disease control of cutaneous breast cancer metastases. Patients with low volume disease and small metastases show the best response to the treatment. Electrochemotherapy is successful in many patients after a single treatment and should be considered early as an adjunct to ongoing breast cancer treatment or as sole treatment.