Updated standard operating procedures for electrochemotherapy of cutaneous tumours and skin metastases

Abstract

Electrochemotherapy is now in routine clinical use to treat cutaneous metastases of any histology, and is listed in national and international guidelines for cutaneous metastases and primary skin cancer. Electrochemotherapy is used by dermatologists, surgeons, and oncologists, and for different degrees and manifestations of metastases to skin and primary skin tumours not amenable to surgery. This treatment utilises electric pulses to permeabilize cell membranes in tumours, thus allowing a dramatic increase of the cytotoxicity of anti-cancer agents. Response rates, often after only one treatment, are very high across all tumour types. The most frequent indications are cutaneous metastases from malignant melanoma and breast cancer. In 2006, standard operating procedures (SOPs) were written for this novel technology, greatly facilitating introduction and dissemination of the therapy. Since then considerable experience has been obtained treating a wider range of tumour histologies and increasing size of tumours which was not originally thought possible. A pan-European expert panel drawn from a range of disciplines from dermatology, general surgery, head and neck surgery, plastic surgery, and oncology met to form a consensus opinion to update the SOPs based on the experience obtained. This paper contains these updated recommendations for indications for electrochemotherapy, pre-treatment information and evaluation, treatment choices, as well as follow-up.

Calcium electroporation for recurrent head and neck cancer: A clinical phase I study

“…To ensure a high concentration of calcium in the tissue, the tumor was treated in smaller sections alternating between direct intratumoral injection of calcium chloride (9 mg/ml) and immediately thereafter electroporation, performed in a systematic fashion to cover the treatment area. This technique is similar to electrochemotherapy using intratumoral injection and directly thereafter electroporation, whereas systemic infusion of bleomycin dictates a time‐window of 8 minutes to allow distribution of drug from the systemic circulation to the tumor . As we injected calcium locally, pulses were administered immediately thereafter.…”

“…For electroporation, we used a Cliniporator (model EPS02, IGEA, Carpi, Italy), which delivers a series of eight consecutive pulses of 0.1 msec each with 1 kV/cm and a frequency of 1 Hz or 5000 Hz . The electrodes (IGEA, Carpi, Italy) could be chosen according to the anatomic locations as either a small, flexible finger‐electrode with linear array needles (10 mm long) or as hexagonal‐ or linear‐electrodes on a handle (20 or 30 mm long) …”

Electrochemotherapy in the Treatment of Breast Cancer Metastasis to the Skin and Subcutaneous Tissue - Multicenter Experience

“…Updated standard operating procedures for ECT were published in 2018. The new guidelines have changed in a way that does not affect the results of this publication, and mainly indicated the possibility of treating large lesions of > 3 cm, which was originally not thought possible [14]. …”

The DAHANCA 32 study: Electrochemotherapy for recurrent mucosal head and neck cancer

“…All patients were treated according to ESOPE guidelines in general anesthesia with a systemic intravenous administration of bleomycin, 15 000 IU/m 2 (Baxter, Denmark). 13 For this initial study, intratumoural injection was not considered to ensure similar dose to all patients. Electroporation was performed from 8 to 28 minutes after bleomycin administration.…”

“…11 Guidelines for the electrochemotherapy treatment procedure are outlined for cutaneous and subcutaneous malignant tumors and metastases by ESOPE (European Standard Operating Procedures of Electrochemotherapy). 12,13 These guidelines were used as a basis for the current protocol.…”