A salutary tale of mistaken identity in testicular cancer.

This case report illustrates the importance of not relying on imaging alone. A 26-year-old patient underwent an orchidectomy for mature teratoma; however, as he had abdominal lymphadenopathy, he was treated with 2 cycles of chemotherapy followed by retroperitoneal lymph node dissection. The abdominal histology revealed mature teratoma and he remained on intense surveillance. Three years later, computerized tomography (CT) indicated he had lung lesions and left hilar lymphadenopathy and, despite normal tumor markers, he was thought to have relapsed. He was treated with 2 cycles of second-line chemotherapy but there was no change in the lung lesions. He underwent a CT-guided biopsy which diagnosed sarcoidosis. He was kept under observation by the respiratory physicians and remains well. Sarcoidosis is commonly associated with lymphoma among other malignancies. In the Mayo series, they concluded there was a strong association between sarcoidosis and teratoma but cautioned against a causal relationship as both diseases are rare and found in the same age group. This case report reminds us to always consider the differential diagnoses, particularly if the imaging does not fit the rest of the clinical picture, and when in doubt obtain histology prior to treatment.