BCL-2 expression and inhibin-A in adrenal neoplasms: A comparative study

Differential diagnosis between adrenal cortical and adrenal medullary lesio ns may be difficult in many cases. Different immunohistochemical, histochem ical tools as well as ultrastructural diagnostic techniques have been emplo yed to aid in differentiating between these lesions. Recently, both inhibin -A and BCL-2 have been shown to stain selectively adrenal cortical tissue a nd its derived neoplasms but not adrenal medulla or pheochromocytomas. In t his study we compared the staining reactions of inhibin-A and BCL-2 in case s of adrenal cortical adenomas and carcinomas as well as pheochromocytomas. We found that both inhibin-A and BCL-2 stained cortical derived tissues, b ut not medullary derived tissues. Staining intensity for inhibin-A was sign ificantly weaker than for BCL-2. We found that fixation techniques may infl uence the staining reactivity, as some cases did not immunoreact with any o f the antibodies. We conclude that both inhibin-A, and, preferentially, BCL -2 are useful additions to a staining protocol to help in the differential diagnosis of cortical and medullary neoplasms.