Vimentin expression in 98 breast cancers with medullary features and its prognostic significance.

The expression of vimentin, as assessed by immunohistochemistry, has been evaluated in 69 medullary carcinomas of the breast: 28 typical medullary carcinomas (TMC), 41 atypical medullary carcinomas (AMC), and 29 invasive ductal carcinomas with subtle medullary features that, however, did not fulfill the strict criteria of TMC or AMC. Immunoreactivity of at least 10% of the component cells was found in 14 of the medullary carcinomas (5 out of 28 TMC, 9 out of 41 AMC whereas only 1 of the invasive ductal carcinomas was vimentin-positive. The patients were followed for 8-13 years. No difference in recurrence-free survival or overall survival could be documented between vimentin-positive and vimentin-negative carcinomas with medullary features. No biological significance could be established for vimentin labelling in these lesions.