Follicular Dendritic Cell Sarcoma Cyril Fisher, MD, DSc, FRCPath Key Facts Terminology Malignant tumor of follicular dendritic cells Clinical Issues Over 1/3 arise in extranodal sites Can metastasize to lymph…

Rosai-Dorfman Disease of Soft Tissue Elizabeth A. Montgomery, MD Key Facts Terminology Lesional histiocytes contain variable numbers of intact lymphocytes within their cytoplasm Phenomenon referred to as lymphophagocytosis or emperipolesis…

Tumoral Calcinosis Julie C. Fanburg-Smith, MD Cyril Fisher, MD, DSc, FRCPath Key Facts Terminology Extraskeletal soft tissue calcification with granulomatous response Clinical Issues Most cases < 20 years Some familial…

Granular Histiocytic Reacton Julie C. Fanburg-Smith, MD Aaron Auerbach, MD Key Facts Terminology Post-surgery collections of histiocytes with granular cytoplasm collecting at site of surgical trauma Microscopic Pathology Histiocytes with…

Crystal-Storing Histiocytosis Cyril Fisher, MD, DSc, FRCPath Key Facts Terminology Soft tissue aggregate of macrophages containing crystalline material Etiology/Pathogenesis In low-grade B-cell lymphomas Monoclonal gammopathy Myeloma Eosinophilic colitis Treatment of…

Polyvinylpyrrolidone Storage Disease Michael R. Lewin-Smith, MD Julie C. Fanburg-Smith, MD Key Facts Etiology/Pathogenesis PVP storage disease is phagocytic foreign body-type reactive condition Found in aerosol hair sprays, adhesives, lithographic…

Intimal Sarcoma Cyril Fisher, MD, DSc, FRCPath Key Facts Terminology Malignant neoplasm arising from intimal aspect of large blood vessels Clinical Issues Pulmonary trunk or pulmonary artery Descending thoracic or…

Silicone Reaction Cyril Fisher, MD, DSc, FRCPath Key Facts Terminology Tissue reaction to silicone (dimethylpolysiloxane) implant, liquid silicone, or silicone gel Etiology/Pathogenesis Leakage from prosthetic implant in breast Cosmetic injection…

Mycobacterial Pseudotumor Elizabeth A. Montgomery, MD Key Facts Terminology Exuberant spindle cell lesion, usually involving lymph nodes, induced by mycobacteria Clinical Issues Immunocompromised patients Majority have AIDS and often also…

Desmoplastic Small Round Cell Tumor Saul Suster, MD Elizabeth A. Montgomery, MD Cyril Fisher, MD, DSc, FRCPath Key Facts Clinical Issues Most common in children and young adults Median age:…