Treatment Outcomes:
Five months after diagnosis of multiple distant metastases, nivolumab was started at a dosage of 240 mg/body weight intravenously every 2 weeks. Palliative irradiation was also provided for painful bone metastases. After four doses of nivolumab, CT showed marked shrinkage of his metastatic lesions [Figure 3]. After 14 doses, the lesion on the left ala of the nose, which had recurred repeatedly, had almost disappeared. After 20 doses, there was improvement in the condition of the skin on the face [Figure 4]. After 21 doses, the dosage of nivolumab was changed to 480 mg/body weight every 4 weeks. Mild leukoplakia appeared around the time of the 26th dose of nivolumab. To date, a total of 50 doses of nivolumab have been administered, and complete remission of metastatic lesions has been maintained for 3 years and 10 months after diagnosis of multiple distant metastases with no severe immune-related adverse events.