Facial nerve paralysis interferes with mimetic muscle function. To reconstruct natural facial movement, free muscle flaps are transplanted as new muscles. However, it is difficult to maintain resting tonus. A dual innervation technique in which other nerves such as the hypoglossal nerve or contralateral facial nerve are added is often applied. Using 10-week-old rats (n = 10), the masseteric and hypoglossal nerves were cut, and the distal stump of the masseteric nerve and the proximal stump of the hypoglossal nerve were then sutured (suture group). In the other group, the masseteric nerve was cut and cauterized (cut group). Immunohistochemistry and microarray were performed on the extracted masseter muscle. The immunohistochemistry results suggested that the muscles in the suture group obtained oxidative characteristics. The microarray showed the genes involved in mitochondrial function, including Perm1. In summary, our data support the validity of the dualinnervation technique for facial paralysis treatment.

Vaginoplasty is a gender-affirming surgery (GAS) for transwomen that laid its foundation in the 1950s and continues to be widely practiced worldwide. We present here a case of a 70-year-old transwoman who underwent lower anterior resection for rectal cancer 12 years after vaginoplasty. The preoperative diagnosis was rectal cancer (Rb-Ra, type 2, cT2N0M0, stage 1). All imaging studies showed a cord-like structure between the prostate and the anterior wall of the rectum, which was thought to be the neovagina. Careful dissection of the anterior rectal wall was required because the distance between the neovagina and the rectum was only 1.5 mm. The role of hormonal therapy and GAS in cancer development in transwomen is unclear. It is important to have regular check-ups for malignancies in patients who have undergone GAS, and if surgical procedures are needed, they should be treated by physicians who are familiar with the procedure.