Serratus Plane Block (SPB) Versus Capsaïcine Versus Botox-A for Chronic Neuropathic Pain in Post-mastectomy Syndrome

Summary

The goal of this phase II clinical trial is to study the effectiveness of a treatment with Serratus Plane Block (SPB) or Botox-A in comparison with capsaicin for the control of chronic neuropathic pain of post-mastectomy syndrom, that is not adequately managed by systemic treatment alone. The primary outcome will be the pain evaluation at 8 weeks.

123 patients with chronic neuropathic pain of post-mastectomy syndrom insufficiently relieved by systemic treatment alone will be recruited over 24 months at the Centre Oscar Lambret.

Patients will be randomly assigned to one of three treatment groups (41 patients per group):

Capsaicin Botulinum toxin A SPB

Patients will be followed for 24 weeks after the study treatment. The follow-up will include remote evaluation and 2 medical visits during which pain and quality of life will be assessed.

Conditions

• Post-Mastectomy Neuropathic Pain Syndrome

Interventions

DRUG

Capsaicin 8% Patch

One or two capsaicin patch (8%) are applied for 60 minutes to the site of neuropathic pain, in day-hospital. An oral, antalgic pre-medication may be done with one of the following medications (alone or association): paracetamol 1g, nefopam 30 mg, tramadol 100 mg, morphine 10mg, oxycodone 5mg. Capsaicin will be administered in addition to a systemic treatment that has been ongoing for at least 4 weeks. If pain persists, the capsaicin patch application may be repeated at 12 weeks.

PROCEDURE

Serratus Plane Block

The Serratus Plane Block (SPB) is a nerve block performed by a trained anesthesiologist to provide localized pain relief. It involves the injection of a local anesthetic: Maximum 150 mg naropeine combined with 150 μg clonidine hydrochloride into the serratus anterior plane under ultrasound guidance. An anesthesiologist will perform the procedure in a post-interventional recovery room, with light sedation.The SBP will be carried out in addition to a systemic treatment that has been ongoing for at least 4 weeks. The SPB may be repeated every two weeks up to four times in the initial 8-week period, with an additional repeat at 12 weeks if pain control remains insufficient.

PROCEDURE

Botulinum Toxin A

Botulinum Toxin A (Botox-A) is injected into the affected area, with a total of 300 units administered across up to 60 injection sites. An anesthesiologist will perform the procedure in a post-interventional recovery room, with light sedation. This intervention will be carried out in addition to a systemic treatment that has been ongoing for at least 4 weeks, and is aimed at providing prolonged pain relief for post-mastectomy neuropathic pain. Light sedation is provided, and injections may be repeated at 12 weeks if necessary.

Sponsors & Collaborators

• Ligue contre le cancer, France

  collaborator OTHER

• Santelys Association

  collaborator OTHER

• CTD-CNO, Caen

  collaborator UNKNOWN

• Centre Oscar Lambret

  lead OTHER

Principal Investigators

• Didier DELBROUCK, Anesthesiologist · Centre Oscar Lambret

Study Design

Allocation

RANDOMIZED

Purpose

TREATMENT

Masking

NONE

Model

PARALLEL

Eligibility

Min Age

18 Years

Sex

FEMALE

Healthy Volunteers

No

Timeline & Regulatory

Start

2026-03-31

Primary Completion

2027-08-30

Completion

2027-12-30

Countries

• France

Study Locations