2022 Volume 75 Issue 4 Pages 182-187
We report the case of a 77-year-old woman with ascending colon cancer with multiple liver and lung metastases. She underwent a right hemicolectomy. The result of postoperative pathological examination was Stage IVb with RAS wild type and BRAF mutation in pT3 pN2b cM1b (HEP, PUL). She received Bevacizumab plus FOLFOXIRI therapy; however, it was discontinued due to the development of diarrhea. Additional mutational analysis found that the tumor had high microsatellite instability; therefore, she was started on Pembrolizumab therapy, which was remarkably effective and the lung metastases disappeared. Two partial hepatectomies were performed with R0 resection. Pathological complete response was confirmed in the resected liver. Recurrence-free survival was 27 months after hepatectomy.
From the results of BEACON CRC study, Encorafenib, Binimetib and Cetuximab combination therapy using BRAF inhibitors can be used after secondary treatment. However, they have a slightly better prognosis than colorectal tumors without MSI and do not have the same response to chemotherapeutics. The discovery of MSI in colorectal tumors highlights the diversity of colorectal cancer and its impact on the professional management of patients.
