Treatment Protocols: ESOPE and Current Practice

Clinical practice in electrochemotherapy was standardised in 2006 by the ESOPE (European Standard Operating Procedures of Electrochemotherapy) project and updated in 2018 to cover deep-seated tumours. This page summarises the core components of the standard and the ranges reported in the corpus.

This page is not a clinical protocol document. The values below summarise the ranges most often reported in published ESOPE documents and in the practice studies within the corpus. What binds in practice is your institution’s approved protocol, the manufacturer’s current instructions for use and the summary of product characteristics for the drug in your country. Dose, electrode and anaesthesia decisions rest with the treating physician on a per-patient basis.

Drug Choice, Dose and Timing

Timing is critical: pulses are delivered in the window when the drug has reached sufficient concentration in the tumour

Agent and route	Reported dose	Pulse timing	Typical context
Bleomycin, intravenous	15,000 IU/m² (≈ 15 mg/m²), bolus over 30–60 seconds	From 8 minutes after injection, not beyond 28 minutes	Numerous or extensive lesions; metastases spread across the body surface
Bleomycin, intratumoural	250–1,000 IU/cm³ by tumour volume (higher per unit volume in small lesions)	1–10 minutes after injection	Few, well-demarcated, small-volume lesions
Cisplatin, intratumoural	Approximately 1 mg/cm³ of tumour volume	Immediately after injection, within a few minutes	Where bleomycin is contraindicated or the cumulative dose limit is being approached

Pulse Parameters: The Two Regimes Compared

Two regimes of the same physical phenomenon; the difference lies mainly in field strength and pulse count

Parameter	Reversible (RE-ECT)	Irreversible (IRE-ECT)
Pulse count	8 pulses (per train)	70–100 pulses
Pulse duration	100 µs	70–100 µs
Field strength	≈1,300 V/cm with plate electrodes, ≈1,000 V/cm with needle electrodes	≈1,500–3,000 V/cm (set as voltage according to electrode spacing)
Repetition frequency	1 Hz or 5 kHz	Synchronised to cardiac rhythm (ECG-gated)
Purpose	Render the membrane transiently permeable without killing the cell	Kill the cell directly; no drug is used

Electrode Types

Electrode choice follows the thickness and depth of the lesion

Electrode	Geometry	Indication	Typical lesion
Type I: plate	Two parallel plates	Superficial, thin (< 1 cm) lesions	Skin metastases, superficial nodules
Type II: linear needle	Two parallel rows of needles	Lesions of intermediate thickness	Cutaneous and subcutaneous tumours
Type III: hexagonal needle	Needle bundle in hexagonal array	Thick, high-volume lesions	Large subcutaneous masses
Variable-geometry long needle	Long needles placed individually under imaging guidance	Deep-seated organ tumours	Liver, pancreas, bone and deep pelvic lesions

Standard Treatment Workflow

The five core steps defined in the ESOPE procedures

Patient and lesion assessment

Lesion number, size, depth and anatomical relations are reviewed, along with cumulative bleomycin exposure, pulmonary function and renal function.

Anaesthesia plan

Local anaesthesia may suffice for a few small superficial lesions. For numerous, extensive or deep lesions, general anaesthesia with neuromuscular blockade is preferred because of the severity of muscle contractions.

Drug administration

The chosen agent and route (intravenous or intratumoural) is administered, opening the defined time window for the electric pulses.

Electrode placement and pulse delivery

The lesion plus a 0.5–1 cm safety margin is covered completely by overlapping electrode applications; the device records current and voltage for each application.

Post-procedure follow-up

Local oedema, erythema, pain and superficial necrosis are expected findings. Response is usually assessed at weeks 4–8, and the session repeated if needed.

Calcium Electroporation: A Drug-Free Alternative

A recently investigated approach replaces the cytotoxic drug with high-concentration calcium chloride. Calcium flooding into the cell after electroporation causes cell death through ATP depletion and loss of homeostasis.

Its appeal is that it removes the systemic toxicity and cumulative-dose constraints that come with a chemotherapeutic agent. The corpus contains publications on calcium electroporation, but the evidence base is markedly narrower than for bleomycin-based electrochemotherapy and the method is mostly applied within clinical research.