[A Case of Sigmoid Colon Cancer with Bladder Invasion Successfully Treated with Chemotherapy with mFOLFOX6+Cetuximab]

A 70' woman presented to our hospital complaining of a weight loss and loss of appetite. She was diagnosed with advanced sigmoid colon cancer by colonoscopy, and CT scan showed that the tumor had invaded the bladder and left ovary, and showed enlarged para-aortic lymph nodes. The tumor was large, and it was determined that a total cystectomy was necessary for radical resection, it was decided to perform pre-operative chemotherapy. Because RAS gene has no mutation, the regimen chose mFOLFOX6, in addition to cetuximab. Although Grade 3 neutropenia was observed, there was no appearance of adverse events that were intolerant, and 6 courses were performed. The treatment resulted in a marked reduction of the tumor. An open sigmoid colon resection with bladder wall and left ovarian cyst were performed. Even after the operation, the course was good, and it was discharged from the hospital lightly on the 10th day after the operation. The histopathological diagnosis was moderately differentiated adenocarcinoma, ypT4b(bladder left ovary), ypN0, M0, ypStage Ⅱc, all with negative surgical margins. She remained recurrence-free for 6 months of postoperative follow up. Cetuximab combination regimen was considered to be an effective option.