A 51-year-old male with a long history of tobacco smoking presented to the outpatient clinic with left renal colic. A renal ultrasound revealed a mass in the left kidney. The patient was admitted to surgical clinic of Russian Scientific Center of Roentgen-Radiology of Rosmedtechnology. A renal biopsy and subsequent histopathological tests revealed adenocarcinoma of the right kidney of most likely metastatic origin. This discovery has lead to vigorous diagnostics search for the primary tumor. Finally, the following diagnosis was established: Primarily-multiple synchronous cancer: cancer of the left kidney T1N0M0, cancer of the thyroid gland T2N0M1, metastasis to the right kidney and lungs. The patient had left kidney and thyroid gland removed and was successfully treated with radioiodine therapy. The patient remains alive and well 7 months since his admission to our clinic. We report this case to emphasize the importance of the renal biopsy and thorough histological analysis, which made it possible to diagnose thyroid cancer in this patient.