[Morphologic changes in primary tumor due to neoadjuvant chemotherapy in breast cancer patients]

The use of chemotherapy as a form of primary treatment for breast cancer is increasing and, as a result, more resection specimens contain tumours which have been exposed to cytotoxic drugs. We have studied the effects of primary chemotherapy on the tumour morphology of breast carcinoma in a group of 77 patients. Characteristic morphological changes, related to the administration of cytotoxic agents, are seen in responded patients. The malignant cells become enlarged with vacuolated cytoplasm and vesicular nuclei containing prominent nuclei; occasionally the nuclei were angular and hyperchromatic. In most cases the stroma was found increased. These features are interpreted as degenerative in nature. It is important to be aware of these effects when studying breast carcinomas removed after chemotherapy.