Erdheim-Chester disease is a rare non-Langerhans-cell histiocytosis involving bones and multiple organs. Its clinical course can vary, from an asymptomatic state to a fatal disease, with renal involvement being a common cause of death. A 41-year-old man presented with a 10-month history of bilateral lower limb pain. Left perirenal soft-tissue infiltration had been found incidentally two years earlier. No progression of the lesion or deterioration of renal function was observed for a period of two years. At admission, plain radiography and magnetic resonance imaging of the patient's lower limbs showed patchy osteosclerosis. Biopsy of the tibia revealed histiocytic infiltration, which was found to be positive for CD68 and negative for CD1a. This report describes an unusual case of Erdheim-Chester disease involving a stationary course of disease with no specific treatment for a long period of time.

Phyllodes tumor is an uncommon fibroepithelial neoplasm of the breast. And it is characterized by expanded stroma with increased cellularity and elongated epithelium-lined clefts. Mammary carcinomas within phyllodes tumors have been rarely reported. To date, however, no reports have described the invasive cribriform carcinoma arising in malignant phyllodes tumor. Here, we report a 62-year-old woman who presented with a large breast mass. Microscopically, the mass was a typical malignant phyllodes tumor showing well developed leaf-like architecture and stromal overgrowth with high cellularity and nuclear pleomorphism. In a portion of the tumor, however, the epithelial component showed a cribriform pattern of proliferation in the absence of myoepithelial cells, suggestive of the invasive cribriform carcinoma. To our knowledge, this is rare and it is difficult to make a differential diagnosis of it. Here, we report our case with a review of literatures.