Electrochemotherapy has been proven to be an efficient treatment for cutaneous metastases of various cancers. Data on breast cancer (BC) patients with cutaneous metastases were retrieved from the INSPECT database. Patients were divided by their receptor status: HER2+, HR+ (ER/PgR+), and TN (triple negative). Groups were similar for histological subtype and location of the nodules. Most patients were previously treated with surgery/systemic therapy/radiotherapy. We found no differences in the three groups in terms of response ratio (OR per patient 86% HER2+, 80% HR+, 76% TN, p = 0.8664). The only factor positively affecting the complete response rate in all groups was small tumor size (<3 cm, p = 0.0105, p = 0.0001, p = 0.0266, respectively). Local progression-free survival was positively impacted by the achievement of complete response in HER2+ (p = 0.0297) and HR+ (p = 0.0094), while overall survival was affected by time to local progression in all groups (p = 0.0065 in HER2+, p < 0.0001 in HR+, p = 0.0363 in TN). ECT treatment is equally effective among groups, despite different receptor status. Response and local tumor control seem to be better in multiple small lesions than in big armor-like lesions, suggesting that treating smaller, even multiple, lesions at the time of occurrence is more effective than treating bigger long-lasting armor-like cutaneous lesions.

The aim of this multicenter study was to evaluate the effectiveness and safety of electrochemotherapy (ECT) for the treatment of mucosal tumors in the head and neck. A total of 71 patients with 84 nodules of different histologies in the oral cavity, pharynx and larynx treated by ECT were evaluated. The data were collected from the InspECT database from 10 participating centers throughout Europe. Primary and recurrent/secondary tumors of different histologies were treated. The overall response rate was 65 %, with a 33 % complete response rate with limited side effects. The response rates of the primary and secondary tumors were not different. However, smaller tumors responded better than tumors larger than 3 cm in diameter. Furthermore, the tumors that were treated with curative intent responded significantly better than those treated with palliative intent. This study demonstrated the feasibility, safety and effectiveness of ECT in a larger cohort of patients with mucosal lesions in the head and neck region. Based on the available data, ECT can be used for the treatment of recurrent and, in some cases, primary mucosal tumors located in the oral cavity, larynx, and pharynx. A better response was obtained in patients with smaller primary tumors treated with curative intent.