This cohort observed partial responses in patients with appendiceal carcinoma (ATM S1599* mutation), cholangiocarcinoma (ATM G1676fs mutation), and urachal adenocarcinoma (PALB2 R170fs14 mutation), along with three cases of prolonged stable disease in patients with mutations in Fanconi Anemia genes and ATM mutations. The gene discussed is ATM; the disease is cholangiocarcinoma.