A Case of a Metastatic Small Bowel Tumor Resected during Chemotherapy for Reccurent Malignat Melanoma of the Nasal Cavity

Abstract

The patient was a 66-year-old man who underwent resection of malignant melanoma of the nasal cavity at the Department of Otolaryngology in our hospital in June 2018. After that, he had been followed up by the Department of Otolaryngology and Head and Neck Surgery in the neighboring university hospital. He had local recurrence in the posterior nares in February 2019 and underwent endoscopic sinus surgery. Then he was treated with immunotherapy, a total of 18 courses of nivolumab as postoperative adjuvant chemotherapy. Again, recurrence of retropharyngeal lymph nodes was confirmed in November 2019 and he was converted to another immunotherapy with pembrolizumab, a total of 2 courses, followed by proton beam therapy. Then, he was referred to the Department of Gastroenterology in our hospital in June 2020 for the examination of abdominal pain and progressive anemia which occurred a month earlier. Further examination revealed an ileal tumor about 100 cm proximal to the terminal ileum, which could not be reached by the preoperative endoscope. He was diagnosed preoperatively as having a malignant tumor of the small intestine, and laparoscopic partial ileal resection plus lymph node dissection was performed in July. Postoperative pathological diagnosis was metastatic small bowel tumor of malignant melanoma. The postoperative course was uneventful. Immunotherapy with pembrolizumab was resumed and is still sustained in an outpatient setting.