Comparing capsaicin patch, Botox‑A injections, and a serratus plane nerve block for chronic post‑mastectomy neuropathic pain
Serratus Plane Block (SPB) Versus Capsaïcine Versus Botox-A for Chronic Neuropathic Pain in Post-mastectomy Syndrome
This trial will test whether a capsaicin 8% patch, Botox‑A injections, or a serratus plane nerve block reduces chronic neuropathic pain in women after mastectomy whose pain is not controlled by systemic treatment.
Quick facts
| Phase | Phase 2 |
|---|---|
| Study type | Interventional |
| Enrollment | 123 (estimated) |
| Ages | 18 Years and up |
| Sex | Female |
| Sponsor | Centre Oscar Lambret Academic / other |
| Drugs / interventions | chemotherapy |
| Locations | 1 site (Lille, Hauts-de-France) |
| Trial ID | NCT06807164 on ClinicalTrials.gov |
What this trial studies
This is a randomized, open‑label Phase II trial enrolling 123 women with chronic post‑mastectomy neuropathic pain not adequately relieved by systemic therapy, randomized 1:1:1 to receive either an 8% capsaicin patch, botulinum toxin A injections, or a serratus plane block. Randomization is stratified by baseline pain level, axillary dissection, prior radiotherapy, and prior change in systemic treatment, and treatments are given 1–2 weeks after randomization. The primary outcome is pain measured at 8 weeks, with patients followed for 24 weeks including remote assessments and two in‑person visits to monitor pain, quality of life, and safety. The trial is conducted at Centre Oscar Lambret in Lille and uses standardized neuropathic pain questionnaires (DN4, NPS, NPSI) and quality‑of‑life measures (SF‑12, HADS).
Who should consider this trial
Good fit: Women aged 18 or older with unilateral breast surgery 3–9 months earlier who have localized moderate‑to‑severe neuropathic pain (NPS ≥3 and DN4 ≥4) not adequately controlled after at least 4 weeks of recommended systemic therapy are the intended candidates.
Not a fit: Patients with non‑neuropathic pain, pain outside the defined localized area or time window, bilateral disease, well‑controlled pain on systemic therapy, or contraindications to any of the local interventions are unlikely to benefit from enrollment.
Why it matters
Potential benefit: If successful, one of these localized treatments could reduce pain and improve quality of life for women whose post‑mastectomy neuropathic pain is not relieved by oral medications.
How similar studies have performed: High‑concentration capsaicin patches and botulinum toxin A have shown benefit in some focal neuropathic pain settings while serratus plane blocks are established for perioperative analgesia but using these three approaches specifically for chronic post‑mastectomy neuropathic pain is relatively novel and evidence is mixed.
Eligibility criteria
Show full inclusion / exclusion criteria
Inclusion Criteria :
1. Women aged ≥ 18 years;
2. Unilateral breast cancer treated by total or partial mastectomy:
* with sentinel lymph node technique (SLN) or axillary dissection;
* with or without immediate reconstruction using a prosthesis;
* associated or not with radiotherapy and/or chemotherapy;
3. Presenting moderate to severe chronic neuropathic pain, defined by:
* Numerical Pain Scale (NPS) ≥ 3 and DN4 ≥ 4,
* on a localised aera ((≤ 240 cm²), at the surgical site, in the axillary hollow, or on the inner side of the ipsilateral arm,
* between 3 and 9 months after breast surgery,
* with indication of additional locoregional treatment in complement to a systemic treatment of chronic neuropathic pain, as recommended by the SFETD - French Society for the Study and Treatment of Pain (tricyclic antidepressants or IRSNA or gabapentinoid PLUS lidocaine patch, at the appropriate dosage) and implemented for at least 4 weeks;
4. Patient affiliated with a health insurance plan;
5. Patient informed and having consented to participate in the trial.
Exclusion Criteria :
1. Ipsilateral breast cancer recurrence, regardless of the first treatment;
2. History of breast or thoracic surgery prior to mastectomy with residual pain;
3. Painful polyneuropathy related to chemotherapy requiring treatment;
4. Ongoing or planned loco-regional adjuvant radiotherapy within the next 8 weeks;
5. Treatment area not suitable for potential botulinum toxin type A treatment;
6. Breast reconstruction using flap or lipomodelling;
7. Indication for breast reconstruction within the next 8 weeks;
8. Chronic pain of another etiology such as:
* Neuropathic pain secondary to a neuroma (localized pain),
* Radiodermatitis,
* Phantom breast pain,
* Lymphedema,
* Complex regional pain syndrome,
* Adhesive capsulitis,
* Fibromyalgia;
9. Hypersensitivity or allergy to anesthetics, capsaicin, naropein, clonidine hydrochloride, an amide-type local anesthetic, botulinum toxin type A, or any excipient contained in the preparations;
10. Infection or inflammation at the injection site;
11. Therapeutic/effective anticoagulation;
12. Clinical signs or medical history leading to the diagnosis of:
* Hemostasis disorder,
* Local infection,
* Severe renal insufficiency (creatinine clearance \< 30 mL/min),
* Thrombocytopenia \< 50,000 platelets/mm3;
13. Generalized muscle activity disorders (e.g., myasthenia, Lambert-Eaton syndrome);
14. Heart rate lower than 60/minute;
15. Severe bradyarrhythmia due to sick sinus syndrome or second or third-degree atrioventricular block;
16. State of depression (HADS score ≥ 11);
17. Other contraindication to any of the study treatments;
18. Inability for the patient to follow the study schedule;
19. Inability for the patient or the healthcare team to perform the treatment within 2 weeks;
20. Pregnant or breastfeeding women, women who are able to conceive and who do not use a highly effective method of contraception during the trial and for at least 1 month after the end of treatment ;
21. Patient under guardianship or curatorship.
Where this trial is running
Lille, Hauts-de-France
- Centre Oscar Lambret — Lille, Hauts-de-France, France (Recruiting)
Study contacts
- Principal investigator: Didier DELBROUCK, Anesthesiologist — Centre Oscar Lambret
- Study coordinator: Julien THERY, Project manager
- Email: j-thery@o-lambret.fr
- Phone: +33 (0)3 20 29 59 18
How to participate
- Review the eligibility criteria above with your treating physician.
- Visit the official trial page on ClinicalTrials.gov for the most current contact information and recruitment status.
- Contact the listed study coordinator or principal investigator to request pre-screening. Pre-screening is free and never obligates you to enroll.