[Granular cell tumors of the breast]

The granular cell tumor was first described by Abrikossoff who referred to that lesion as myoblastoma. This lesion is mainly observed in soft tissues and is exceptionally found in the mammary gland. Among the 159 cases of breast granular cell tumor reported in the literature, only 121 have been well documented. Tumors occurred in 15 to 74 year old patients and in only 9.8% of the tumors discovered in males. In breast this tumor may mimic a carcinoma like in the three cases reported. The intra-operative diagnosis on frozen sections may be particularly difficult and the risks to overdiagnose a carcinoma are not negligible and must be known. The diagnosis on paraffin sections is much more easier than on frozen sections. The immunostaining procedures (anti p S100) and electron easier than on frozen section. The immunostaining procedures (anti p S100) and electron microscopy are mainly interesting to document the histogenetic hypotheses. The schwannian origin of the tumor is favoured in most of the recent studies. The granular cell tumors are usually benign and malignant tumors account for only 2.5% of those diagnosed in the breast.