The efficacy of botulinum toxin A in post-mastectomy breast reconstruction: a pilot study

Botulinum toxin A has been successfully used in a variety of areas to temporarily obliterate muscle mobility for either functional or aesthetic gain. Tissue expander-based breast reconstruction has been plagued with pain and discomfort.

The purpose of this pilot study was to evaluate the role of a neurotoxin (Botulinum toxin A) in expander-based breast reconstruction.

Thirty patients underwent mastectomies with immediate expander or acellular dermal matrix reconstruction. The neurotoxin group (n = 15) received 40 units of neurotoxin (Botulinum toxin A, Allergan, Inc, Irvine, CA) into each pectoralis major muscle through 4 serial injections and the placebo group (n = 15) received 4 serial injections of 0.9% NaCl. All patients were followed over 1 year, and patient demographics, VAS (visual analog score), laterality, office visits, amount of expansion and number of times to full expansion, and amount of narcotics required were recorded. Statistical significance was considered as p < .05.

There were no significant differences between the two groups in terms of age, laterality, expander size, or complications (p = .46-.66). There was a significant difference between the two groups in the VAS score, demonstrating decreased pain in the neurotoxin group (p < .05). In addition, there was a significant increase in the volume of expansion per visit in the neurotoxin group as compared to the placebo group (p < .05). There was no significant difference in narcotic use in the first 3 days after surgery; however, there was a significant decrease in use of narcotics from 7 to 45 days in the neurotoxin group (p < .05). There were no complications associated with the use of the neurotoxin.

The infiltration of the pectoralis major muscle with neurotoxin in immediate, expander-based reconstruction may be beneficial in reducing pain and expediting expansions.