Granular cell tumour of the breast

Four cases of granular cell tumour of the breast reflecting the lifetime experience of one surgeon are presented. Recent advances in the pathology of this condition suggest that the customary term 'myoblastoma' is inappropriate, and that 'granular cell tumour' is preferable. The clinical and pathological features are reviewed and the differential diagnoses discussed, with emphasis on the distinction from carcinoma which may be mimicked both clinically and on frozen examination. The diagnosis may be made by pre-operative aspiration cytology, and a conservative surgical approach is recommended.