Testicular Metastasis From Small Cell Lung Carcinoma: A Case Report.

Testicular involvement from small cell lung carcinoma (SCLC) is extremely uncommon and diagnostically challenging. Awareness of this rare metastatic pattern is essential, particularly in patients presenting with new scrotal symptoms during disease progression. We report the case of a 61-year-old North African male patient with previously treated SCLC who developed progressive right testicular enlargement at metastatic relapse. Scrotal ultrasound described a 41-mm heterogeneous intratesticular mass. Serum alpha fetoprotein and β-HCG were within normal limits. No orchiectomy was performed due to disseminated disease, declining performance status, and the lack of therapeutic benefit of local surgery. Ultrasound images could not be retrieved, but the radiology report was available. The patient underwent systemic chemotherapy rechallenge and palliative radiotherapy. This case illustrates the diagnostic challenges of testicular metastasis in advanced SCLC, highlights the sanctuary-site concept, and emphasizes the importance of clinical context when histologic confirmation is not feasible.