Rhabdomyosarcoma of breast.

Rhabdomyosarcoma of the breast is an extremely rare condition. Billroth (1860) described such a tumour in the left breast of a young girl aged 16 years. It was a large unencapsulated neoplasm and was composed of elongated muscle cells with distinct cross-striations and large granular myoblasts. The tumour recurred after local excision. The subsequent history of the patient was not recorded. Sailer (1937) gave an account of a rhabdomyosarcoma which occurred in the breast of a coloured woman aged 38 years. Local removal of this tumour was also followed by a recurrence lateral to the scar. The patient died shortly afterwards of intestinal obstruction, and at the post-mortem examination rhabdomyosarcomatous deposits were found in the walls of the stomach and jejunum, and of the ileo-caecal valve, causing intussusception. Metastases were also demonstrated in the liver and lungs. Both the breast neoplasm and the visceral tumours were composed of myoblasts with deeply staining nuclei placed centrally and eccentrically in a granular cytoplasm. Occasional elongated, ribbon-like fibres with distinct longitudinal striations were also present. Small polyhedral spindle cells and strands of connective tissue were found interspersed between the muscle cells. Distinct cross-striations were demonstrated in many of the cells. Govan (1945) described rhabdomyoblastic cells in two mixed malignant tumours of the breast. These cells were mainly of the spindle type. Scattered among these were giant cell forms frequently multinucleated. Some cells were described as strap-shaped, fan-shaped, tadpole-like, or of a modified spider form. In the large cells longitudinal striation was well defined, but cross-striation was limited to beading of the cell