Paclitaxel inhibits post-traumatic recurrent laryngeal nerve regeneration into the posterior cricoarytenoid muscle in a canine model.

OBJECTIVES/HYPOTHESIS: To investigate the efficacy of paclitaxel, a potent microtubule inhibitor with a more favorable therapeutic index as compared with vincristine, in preventing post-traumatic nerve regeneration of the recurrent laryngeal nerve into the posterior cricoarytenoid muscle in a canine laryngeal model.

STUDY DESIGN: Experimental animal study.

METHODS: Forty-nine canine hemilaryngeal specimens were divided into five experimental groups. Under general anesthesia, a tracheostomy, recurrent laryngeal nerve (RLN) transection and repair, and laryngeal adductory pressures (LAP) were measured pre-RLN injury. The approach to the posterior cricoarytenoid (PCA) muscle for neurotoxin injection was transoral or open transcervical, at 0 or 3 months. At 6 months, postinjury LAPs were measured and the animals were sacrificed at 6 months to allow for laryngeal harvesting and analysis.

RESULTS: Paclitaxel demonstrated increased mean laryngeal adductory pressures (70.6%) as compared with saline control (55.5%). The effect of paclitaxel was the same as observed with vincristine at 0 months and with a delayed injection at 3 months. There was no difference between transoral or open injection groups.

CONCLUSIONS: PCA muscle injection with paclitaxel resulted in improved strength of laryngeal adduction. This effect was similar to that of vincristine at both 0 and 3 months following nerve injury. A single intramuscular injection of paclitaxel was well tolerated. Additional human studies are needed to determine the degree of clinical benefit of this intervention.

LEVEL OF EVIDENCE: NA Laryngoscope, 127:651-655, 2017.