A case of mineralocorticoid intermediate-producing sarcomatoid adrenal cortical carcinoma: case report and review of literature.

Sarcomatoid adrenal cortical carcinoma (SACC) is an extremely rare histological subtype accounting for only 0.2% of all adrenal cortical carcinomas. Most reported cases of SACC are nonfunctional, showing a biphasic histological pattern with both epithelial adrenocortical carcinoma and sarcomatous components, which are often associated with poor prognosis. Herein, we report a unique case of SACC with characteristics distinct from those previously documented. A 66-year-old man presented with uncontrolled hypertension, night sweats, exertional dyspnea, and palpitations. Imaging revealed an 11 cm mass in the left adrenal gland. Laboratory results indicated hypokalemia with suppressed plasma renin and aldosterone levels and the presence of mineralocorticoid intermediates, notably elevated deoxycorticosterone (DOC), detected via LC-MS/MS. The patient underwent a left adrenalectomy. Histologically, the tumor consisted solely of spindle cells without the typical adrenocortical carcinoma components. Immunohistochemical analysis demonstrated partial positivity for steroidogenic enzymes, including 3β-hydroxysteroid dehydrogenase, cytochrome P450 family 21 subfamily A member 2 (CYP21A2) and cytochrome P450 family 11 subfamily B member 1 (CYP11B1). This finding was consistent with RNA expression analysis, supporting the synthesis of mineralocorticoid intermediates within the tumor. However, the discrepancy between the measured steroid intermediate metabolites and enzyme expression patterns in the tumor, as indicated by immunostaining and mRNA levels, suggests that the steroid production pathway in this tumor remains partially unclear. Two years postoperatively, the patient has remained free from recurrence or metastasis. This case holds particular value, as it is the first report to describe hormone production in a SACC composed solely of spindle cells.