Cortical versus medullary XXXX : a useful morphologic distinction?

@entity1 @entity704 @entity5 @entity4755 @entity9075
We have tested the hypothesis that @entity704 can be classified solely on the basis of epithelial cell morphology and that this distinction is prognostically useful. One @entity9075 were classified according to the morphologic resemblance to cortical or medullary thymic epithelium and to the traditional classification (lymphocytic, epithelial, mixed, and spindled). Follow-up data was obtained on 78 @entity1 . Fifty-eight percent of the @entity5 were invasive. Nineteen of the invasive @entity5 relapsed and none of the non-invasive @entity5 relapsed (P less than .0001). Four of nine @entity5 with microscopic invasion through the capsule recurred. Statistical analysis showed no significant differences in relapse-free survival for any of the histologic categories. Ninety-four percent of the @entity5 studied were keratin positive and all were chromogranin negative. Carcinoembryonic antigen was negative for all but one cytologically malignant @entity5 ; of the @entity5 75% were epithelial membrane antigen positive, 80% were @entity4755 positive, and 11% were neuron specific enolase positive. Seven of 12 @entity5 tested expressed HLA-DR. There was no correlation between immunoreactivity and classification. The morphologic cortical/medullary distinction is conceptually attractive but appears clinically to be no more advantageous than the traditional classification.
