A Colorectal Cancer with Invasive Micropapillary Carcinoma

: A 76-year-old woman with bloody stool visited a nearby hospital. Colonoscopy showed a type 1 tumor in the rectum, and the biopsy indicated moderately differentiated adenocarcinoma. She was referred to our hospital. Abdominal contrast-enhanced CT did not show swollen lymph nodes in the regional nodes or distant metastases. Laparoscopic lower anterior resection was performed. Histopathological examination indicated pT1b, pN3, ly3, and v1, fStage III b, which had a partial invasive micropapillary carcinoma(IMPC)component of papillary adenocarcinoma. Although she received postoperative adjuvant chemotherapy, she died of a thromboembolism with paraneoplastic syndrome 20 months after the operation. IMPC has a high incidence of lymphatic invasion and lymph node metastases. IMPC is rare in cases of colorectal cancer and it is important to accumulate and investigate colorectal cancer patients with IMPC.