[Malignant phyllodes tumour : a case report].

A 28 year old woman has suffered over the previous month from a post-traumatic swelling sensation of the left breast. Ultrasonography demonstrates a 9 cm, sharply-cut, rounded, hypo-echogenic lesion. Surgery is performed, with the hypothesis of an haematoma. The pathological analysis of the lesion shows a malignant phyllodes tumour with heterologous rhabdomyosarcomatous features. No metastasis is found. A radical mastectomy is performed and the patient benefits from an adjuvant radio-chemotherapy. Phyllodes tumours represent up to 1 % of all mammary cancers, with 10-20 % of malignant lesions. These tumours behave differently from usual breast cancers. This atypical case, arising in a traumatic context, provides the opportunity to discuss the treatment and classification of phyllodes tumours of the breast.