Sub-cutaneous histiocytic sarcoma in a child: a case report.

Background: Histiocytic sarcoma (HS) is a rare hematologic malignancy with morphologic and immunophenotypic evidence of histiocytic differentiation. This tumor follows an aggressive clinical course.

Case Presentation: We report the case of a 14 year-old white girl who presented with a nodular lesion in the thigh, involving the skin and soft tissue.

Malignant phyllodes tumor of the breast with liposarcomatous differentiation and intraductal hyperplasia.

Phyllodes tumor of the breast is a biphasic fibroepithelial neoplasm. 10 to 20% of phyllodes tumor show malignant transformation, often in the form of stroma, which usually shows fibrosarcomatous differentiation and rarely heterologous sarcomatous elements. Liposarcomatous differentiation is not common among phyllodes tumors.

[Retroperitoneal Castleman disease].

Castleman disease or angiofollicular lymph node hyperplasia is a rare disease of unknown cause with polymorphic clinical features that raises many diagnostic and therapeutic problems. The unifocal, localized, pseudoneoplastic form, first described in 1956, has a good prognosis, but the multifocal form has a more aggressive course. Three histological types have been identified: hyaline vascular, plasma cell and mixed.