A case of appendiceal ganglioneuroma in neurofibromatosis type 1.

BACKGROUND Neurofibromatosis type 1 is an autosomal dominant inherited disease associated with multiple skin neurofibromas or other neurogenic tumors, such as nodular plexiform neurinoma or cerebrospinal tumor. Gastrointestinal stromal tumors are often complicated in patients with neurofibromatosis type 1, although involvement of the appendix is rare, and there have been few reports of appendiceal ganglioneuroma. CASE PRESENTATION The patient was a 29-year-old man diagnosed with neurofibromatosis type 1 based on physical findings and his family history. During the follow-up of neurofibromatosis, computed tomography was performed to detect neurological tumors, such as neurofibromas in the brain, spinal cord, and gastrointestinal tract. Computed tomography showed a markedly thickened appendix wall, and an appendiceal tumor was suspected. Laparoscopic appendectomy was performed, and a 50 × 35 mm appendiceal submucosal tumor was resected with a negative resection margin. At histopathological examination, the tumor was diagnosed as ganglioneuroma; it showed short spindle-shaped cells and ganglion cells diffusely infiltrated into the proper muscle layer and fibrous tissue that grew around nerve cells. The patient was discharged on the 5th postoperative day without postoperative complications and was doing well at 13 months following the operation. CONCLUSIONS Gastrointestinal stromal tumor and neurofibroma are the most common gastrointestinal tumors associated with neurofibromatosis type 1, but ganglioneuroma of the appendix is rare. Appendiceal neurogenic tumors should be considered in patients with neurofibromatosis type 1, and surgical resection is necessary because of the risk of malignancy.