Urothelial carcinomas (UCs) can occur in the upper urinary tract or lower urinary tract. Upper urinary tract urothelial carcinoma (UUT-UC) is relatively a rare disease and accounts for only about 5% of UC cases. Sporadic cases of late-onset metastasis, associated with UC of the bladder, have occasionally been reported. In contrast, no late-onset distant metastatic UUT-UC without local recurrence has, to the best of our knowledge, been reported in the English literature. We report an extremely rare case of distant metastatic UC, mimicking lung adenocarcinoma that originated from UUT-UC 12 years previously.