Sporadic Pheochromocytoma: Anapathologic, Immunohistochemical and Cytogenetic Aspects Associated with the Occurrence of Metastasis: A Literature Review

The safe distinction between benign and malignant pheochromocytomas is still an unsolved problem from the standpoint of the pathological diagnosis. In most cases, the decision is thus based on the occurrence of metastasis as the only unambiguous evidence of malignancy. This paper reviews the literature and shows that, although there are positive correlations between anatomopathological, immunohistochemical and cytogenetic findings, the independent analysis of each factor does not establish the ultimate prognosis of malignancy. It is therefore suggested an integrated wide analysis of all factors in an attempt to predilection o f the metas ta t i c po ten t ia l o f sporad ic pheochromocytomas, especially when there is a positive correlation between all the criteria, particularly in the detection of 5% or more of positive nuclei for MIB-1 or CD44 -S negative immunostaining, or both. When 10 or more chromosomal changes are noticed in comparative genomic hybridization, malignancy should be strongly suggested.