Distribution of mast cells in the axillary lymph nodes of breast cancer patients.

Fifty mastectomy specimens of carcinoma breast were studied for pattern of mast cell distribution in their axillary lymph nodes. When all axillary nodes were free of tumour, the mean mast cell count was 35.75/sq mm. In the metastatic node the mast cell count was inversely proportional to the amount of metastatic tumour. The mast cell number decreased (25.64/sq mm) as the metastasis developed in any of the enlarged axillary nodes. Their count diminished further (23.55/sq mm) as the amount of metastatic tumour increased in individual nodes and when tumour involved all enlarged nodes. Mean mast cell count was lowest (10.50/sq mm) in metaplastic carcinoma. The mast cells in metastatic nodes were found mainly at the edges of tumour deposits.