Immune checkpoint inhibitor resistance in dMMR high-grade intraepithelial neoplasia with lynch syndrome-associated colon cancer: a case report
L T Liu·Xiaojun Xiang·Hongjiao Zhang·Yan He·Juanjuan Zhou·Yi Le·Weiqi Liu·Jinbo Zhan·Ziling Fang·Li Li·Ling Zhou
Immune checkpoint inhibitors demonstrate high efficacy in MSI-H/dMMR colorectal cancer, yet a subset of patients develops resistance. This case reports in situ recurrence in Lynch syndrome-associated colon cancer, with the novel observation that while the recurrent lesion responded completely to immunotherapy, a concurrent dMMR ascending colon adenoma showed resistance. A patient with Lynch syndrome-associated colon cancer experienced in situ recurrence. Immunotherapy led to complete response in