Corticomedullary tumors of the adrenal glands. Report of two cases. Association of corticomedullary tumor with spindle cell sarcoma.

We describe two cases of corticomedullary tumors of the adrenal gland. The patients suffered from Cushings syndrome and paroxysmal hypertension. The corticomedullary tumors consisted of benign looking cortical adenoma cells growing on the background of the pheochromocytoma cells. We further present the ultrastructural and immunohistochemical features of these tumors. Focally a spindle cell sarcoma arising from the corticomedullary tumor was found in one case. The spindle cell sarcoma was immunohistochemically negative with antibodies to chromogranin, synaptophysin, cytokeratin and S-100 protein. Ultrastructurally the sarcoma was composed of undifferentiated primitive cells poorly endowed with cytoplasmic organelles. Focal transitions of the pheochromocytoma into the spindle cell sarcoma were seen. It is hypothesized that the spindle cell sarcoma was arising from the pheochromocytoma component of the corticomedullary tumor.