Pathology of adrenal neoplasms.

The use of immunohistochemistry and electron microscopy enables the strict separation of adreno-cortical and adreno-medullary tumors in every case, as tumors of the medulla are generally positive for neuroendocrine markers (chromogranin A, synaptophysin) and negative for D11 whereas those of the cortex are stained with D11 and are negative with the other markers. Our surgical collection of cortical tumors and tumor-like lesions (n = 104) covers adenomas (39%), carcinomas (15%), microadenomatosis (2%), macronodular hyperplasia (4%), hemangioma (1%), myelolipoma (2%), hematoma (1%), pseudocysts (2%), and metastases (6%). The often difficult interpretation of dignity was aided by a point system of criteria. Isolated nodules were differentiated from adenomas by their size (ie less than 3 cm), the histological pattern and the lack of cellular atypia. Correlations of the lesions with the endocrine functions were presented. The tumors of the medulla (n = 42) were differentiated in pheochromocytomas (88%), malignant pheochromocytomas (7%), neuroblastomas (2%), and ganglioneuroblastomas (2%). 8-10% of pheochromocytomas are malignant, but with the exception of invasion of the capsule or of the veins or the demonstration of metastases, no other reliable criteria for malignancy exist. The lack of S100-protein-immunoreacting satellite cells may indicate a malignant growth. 89% of pheochromocytomas in our collection were shown to be endocrine active secreting catecholamines and in one case additionally ACTH.