Quantitative analysis of mast cells in benign and malignant breast lesions. Immunohistochemical study on formalin-fixed, paraffin-embedded tissues.

Background: It has been reported that the number of mast cells was significantly greater in malignant breast carcinomas than in benign breast lesions. This was due to tryptase-containing mast cells while tryptase, chymase-containing mast cells had no effect. However, analysis of mast cells in breast carcinomas and benign breast lesions based on their histological findings remains to be elucidated.