Here we describe six unrelated patients found to be heterozygous for germline, loss-of-function variants in ATM and diagnosed with at least one malignancy that is not currently associated with the ATM cancer susceptibility syndrome, including gallbladder carcinoma, uterine carcinoma, renal cell carcinoma, duodenal adenocarcinoma, lung adenocarcinoma, and a vascular sarcoma. The gene discussed is ATM; the disease is uterine carcinoma.