The Rare Case of a Sertoli Cell Tumor of the Adrenal Gland in a Man With Pathological Dexamethasone Suppression Test: A Case Report.

Sertoli cell tumors are rare gonadal stromal tumors. Extragenital manifestations, particularly in the adrenal gland, are exceptionally uncommon. We present a case of an adrenal Sertoli cell tumor in a male patient, presenting with a pathological (1 mg overnight) dexamethasone suppression test. An 82-year-old otherwise healthy man was referred for evaluation of an incidentally detected left adrenal mass. The patient was asymptomatic with no clinical signs of catecholamine excess, hypercortisolism, hyperaldosteronism, or B-symptoms. Initial CT scan revealed a 44 × 42 mm lesion, which increased to 50 × 46 mm within three months and showed suspicious washout characteristics. Endocrinological work-up showed a pathological (1 mg overnight) dexamethasone suppression test, while metanephrines and aldosterone testing were normal. Tumor markers [alpha-fetoprotein (AFP), beta-human chorionic gonadotropin (β-HCG)] were unremarkable. A hormonally active adrenal adenoma with autonomous cortisol production was suspected. After discussion at the interdisciplinary tumor board, robotic-assisted adrenalectomy was performed. Complete resection was achieved without complications; the patient was discharged on the third postoperative day. Histopathological examination showed a Sertoli cell tumor with complete excision and no evidence of local infiltration or malignancy. Immunohistochemistry showed positivity for cluster of differentiation (CD)56, CD99, synaptophysin, and partial positivity for SF1, calretinin, and inhibin. Chromogranin A and MART1 were negative. Molecular analysis revealed no FOXL2 or DICER1 mutations. Postoperatively, hydrocortisone replacement was initiated due to a submaximal cortisol response to adrenocorticotropic hormone (ACTH) stimulation testing. At six-month follow-up, CT imaging showed no recurrence or metastases, and tumor markers remained normal. Adrenal Sertoli cell tumors represent an extremely rare entity lacking specific management guidelines. In this case, robotic-assisted adrenalectomy proved safe and feasible. We observed good short-term oncological and clinical outcomes. Further reports are needed to clarify hormonal associations and establish standardized follow-up and treatment strategies.