Reduced Postoperative Chronic And Neuropathic Pain With Targeted Nipple Areola Complex Reinnervation In Patients Undergoing Gender Affirming Mastectomy

Purpose: Gender-affirming mastectomy (GAM) is the most frequently performed surgery in patients transitioning from female to male. However, postoperative pain may occur and lead to significant functional, psychological and socioeconomic consequences. Little is known about the incidence of chronic pain including the proportions attributed to neuropathic factors. Targeted nipple areola complex reinnervation (TNR) is a technique that aims to improve sensory outcomes and reduce postoperative pain by preserving and reconnecting all of the lateral intercostal nerves that are transected during mastectomy. This study aims to quantify postoperative chronic and neuropathic pain in patients undergoing GAM. Methods: A total of 50 patients undergoing double incision GAM with free nipple grafts were prospectively enrolled between 2021 and 2022. 26 subjects who underwent GAM with TNR were compared to 24 controls who underwent GAM without TNR. Patient-reported pain outcomes were completed postoperatively at 1, 3, 6, 9 months. Patients were considered to have chronic pain if they reported chest pain during at least two consecutive follow-up time points. Pain intensity was quantified using the visual analogue scale (VAS) on a scale of 1-10. The short form Patient Reported Outcome Measurement Information System (PROMIS) Neuropathic Pain Quality scale was used to report on neuropathic pain based on five neuropathic pain qualities: tingling, stinging, pins and needles, electrical and numb pain. Results: Chest pain was reported in 62.5% of patients at 1 month postoperatively, 40.6% at 3 months, 26.6% at 6 months, 22.9% at 9 months. Chest pain was significantly lower in subjects as compared to controls at 1, 3, 6 and 9 months postoperatively (p<0.05). Throughout the study period, chronic pain was present in 8/26 (33.3%) of subjects and 15/24 (62.5%) of controls (p<0.05). Average chest pain intensity was 3.3 (range 1-10) at 1 month postoperatively, 2.8 (range 1-8) at 3 months and 2.3 (range 1-3) 9 months postoperatively. Average chest pain intensity was similar between subjects and controls throughout the follow-up period (p>0.05). Chest pain had neuropathic pain features at each follow-up visit and proportions of chest pain with neuropathic qualities increased over time (60% at 3 months versus 71.4% at 9 months). Proportions of neuropathic pain were significantly higher in subjects as compared to controls at 6, and 9 months postoperatively (p<0.05). Conclusion: Chronic pain is common following double incision GAM with free nipple grafts. The majority of postoperative chest pain was neuropathic in nature. TNR reduced both chronic and neuropathic chest pain up to 9 months postoperatively.