Ascending colon cancer metastasized to the right testicle: a case report

Background Testicular metastasis from malignant solid tumors is extremely rare. It is usually found by chance during autopsy or pathological examination of testicular specimens. Therefore, we consider it necessary to report our patient’s case of testicular metastasis from colon cancer. Case presentation We report a 61-year-old Han Chinese male patient who presented to our clinic with progressive painless swelling of the right testicle for 2 years. Positron emission tomography–computed tomography scans showed increased 18F-fluorodeoxyglucose metabolism in the right testicle, possibly owing to distant metastasis. His previous medical history suggested that he had undergone laparoscopic-assisted right hemicolectomy for ascending colon cancer 4 years ago. Considering the ascending colon cancer metastasis to the right testicle, we performed a right radical testicular resection through an inguinal approach. Postoperative histological examination showed intestinal metastatic adenocarcinoma. Conclusion Colon cancer metastasis to the testes is uncommon. The clinical and imaging manifestations of this tumor are nonspecific, so the diagnosis relies on postoperative pathology. If testicular metastasis is found, treatment principles for advanced colon cancer should be followed.