ADRENAL-CORTICAL CARCINOMA WITH ADENOSQUAMOUS DIFFERENTIATION - REPORT OF A CASE WITH IMMUNOHISTOCHEMICAL AND ULTRASTRUCTURAL STUDIES

We report the case of an adrenal cortical carcinoma with glandular and squamous differentiation, demonstrated by light and electron microsco py as well as by immunohistochemical studies. The patient was a 63-yea r-old man presenting with a large adrenal mass and markedly increased 24-hour urine metanephrine, initially suggesting the diagnosis of pheo chromocytoma. Upon histological examination of the surgically excised tumor, the presence of adenosquamous differentiation was most consiste nt with a metastasis to the adrenal gland. No other primary tumor was later found at autopsy, however. It thus becomes evident with this cas e that squamous and glandular differentiation can be observed in prima ry adrenocortical carcinomas, and therefore the conventional approach to the immunohistochemical and ultrastructural features of these tumor s is challenged. This type of aberrant morphology in adrenocortical ca rcinomas makes the differentiation from a metastatic carcinoma particu larly difficult for the surgical pathologist. Clinical correlation is absolutely necessary for an accurate diagnosis, and occasionally, as w as the case with this patient, only with postmortem studies can anothe r primary be ruled out with certainty.