Abstract. In this paper, we report a rare case of cecalSignet ring cell carcinoma (SRCC) leucovorin, and irinotecan plus cetuximab). At a follow-up examination nine months after surgery, she was found to be doing well.The existence of microscopic tumor implants in the intestinal wall, distal to the inferior edge of a macroscopic tumor (either continuous or discontinuous with the tumor), is called distal intramural spread (DIS) (1). The rate of DIS in rectal cancer is reported as 14.7% (2) to 83.6% (3). On the contrary, DIS has not been reported in colonic cancer and is considered rare. DIS is classified as continuous or discontinuous lesions. Discontinuous lesions spread from the distal side of the main tumor through the normal epithelium. These lesions are called skip lesions (4). Skip lesions are thought to invade the submucosal or muscular layers through the lymphatic vessels (5, 6).More than 90% of colorectal carcinomas are adenocarcinomas originating from epithelial cells of the colorectal mucosa (7). According to a previous report (8), 2.63% of patients with colonic cancer had Signet ring cell carcinomas (SRCC). In this study we report a rare case of cecal SRCC with DIS diagnosed pathologically.
Case ReportA 71-year-old woman with hypertension and dyslipidemia was referred to another hospital with vomiting, abdominal pain, and abdominal distension. She was suspected of having ileus and was transferred to our hospital. Contrast enema showed a cecal mass. There was no flow of contrast medium into the ileum. Colonoscopy showed complete stenosis of the ascending colon. Pathological examination showed SRCC. Upper gastrointestinal endoscopy did not indicate any neoplastic lesion. Computed tomography (CT) of the abdomen showed a thickening of the cecal wall with fluid accumulation in the distal ileum. Swelling of lymph nodes around the cecum, ascites, and peritoneal metastasis were observed (Figure 1). The level of carcinoembryonic antigen (CEA) was 6.8 ng/ml. Other laboratory results were normal. She was clinically diagnosed with cecal cancer, which caused ileus and carcinomatous peritonitis. Surgery was performed by iliocecal resection with lymphadenectomy. Pathological examination of the resected specimen showed SRCC invading all layers of the cecal wall. There was massive invasion of the lymphatic vessels and venous vessels ( Figure 2) and metastasis to the lymph nodes.A submucosal nodule (diameter, 10 mm) was located 55 mm from the distal side of the main tumor through the normal epithelium (Figure 3). This lesion was also diagnosed as SRCC. It was located in the muscularis propria to subserosa. Because no carcinoma cells were exposed to the epithelium or serosa, we diagnosed the lesion as DIS of cecal SRCC (Figure 4). The final pathological stage was 705