Spontaneous Regression of Duodenal Cancer with a Metastatic Liver Cancer

Abstract

A 61-year-old woman presenting with nausea was found by gastrointestinal endoscopy to have an ulcerative lesion in the second portion of the duodenum. Histological examination of a biopsy specimen revealed poorly differentiated adenocarcinoma. Computed tomography showed a hypovascular mass in the hepatic posterior section. She was recommended to receive chemotherapy following a diagnosis of duodenal cancer with synchronous liver metastasis. After receiving a second and third opinion elsewhere, the patient was finally referred to our hospital 4 months after the symptom onset. Based on a diagnosis of duodenal cancer and a hepatic mass that could not be definitively diagnosed, we conducted pancreaticoduodenectomy and resection of the right posterior hepatic section. Histologically, there was no evidence of viable cancer cells in the resected duodenum or liver, but granulomas with necrosis were observed. In the necrotic area, ghost cells were observed, which resembled cancer cells biopsied from the duodenum preoperatively and were immunohistochemically positive for cytokeratin. These findings suggested that the duodenal cancer and liver metastasis spontaneously disappeared without any treatment. Spontaneous regression of gastrointestinal cancer is rare, and the present report is the first to document a case of spontaneous regression of duodenal cancer.