Basicmedical Key

Fibroma of Tendon Sheath David R. Lucas, MD Key Facts Terminology Small benign fibrous nodule typically attached to tendon sheath Clinical Issues Most common in fingers Macroscopic Features Median size:…

Nuchal Fibrocartilaginous Pseudotumor Cyril Fisher, MD, DSc, FRCPath Key Facts Terminology Metaplastic (pseudoneoplastic) nodule of fibrocartilage originating within nuchal ligament Etiology/Pathogenesis Remote or recent history of neck trauma Clinical Issues…

Nuchal and Gardner Fibroma Elizabeth A. Montgomery, MD Key Facts Terminology Uncommon fibrocollagenous lesion classically arising in cervicodorsal region Some cases linked to familial adenomatous polyposis (FAP)/Gardner syndrome Clinical Issues…

Elastofibroma Cyril Fisher, MD, DSc, FRCPath Key Facts Terminology Pseudotumor composed of fragmented abnormal elastic fibers in collagenous stroma Etiology/Pathogenesis Probably related to trauma or friction Clinical Issues History of…

Keloid and Cellular Scar David S. Cassarino, MD, PhD Key Facts Terminology Scar with prominent thickened and eosinophilic bundles of collagen Clinical Issues Persistence and recurrence are common, but no…

Pleomorphic Liposarcoma Thomas Mentzel, MD Key Facts Terminology Pleomorphic high-grade sarcoma containing variable amounts of pleomorphic lipoblasts Clinical Issues Rarest subtype of liposarcoma Accounts for approximately 5% of all liposarcomas…

Mixed Liposarcoma Thomas Mentzel, MD Key Facts Terminology Liposarcoma showing morphologic/genetic features of combined myxoid liposarcoma and atypical lipomatous tumor/dedifferentiated liposarcoma, or of myxoid liposarcoma and pleomorphic liposarcoma Clinical Issues…

Myxoid Liposarcoma Thomas Mentzel, MD Key Facts Terminology Malignant lipogenic neoplasm composed of primitive nonlipogenic mesenchymal cells and variable number of lipoblasts set in myxoid stroma with characteristic branching blood…

Dedifferentiated Liposarcoma Thomas Mentzel, MD Key Facts Terminology Malignant lipogenic neoplasm showing abrupt or gradual transition from atypical lipomatous tumor to nonlipogenic sarcoma of variable histology Clinical Issues Retroperitoneum, intraabdominal…

Atypical Lipomatous Tumor/Well-Differentiated Liposarcoma Thomas Mentzel, MD Key Facts Terminology Intermediate (locally aggressive, nonmetastasizing) lipogenic neoplasm composed of atypical adipocytes Clinical Issues Accounts for 40-45% of all liposarcomas Occurs most…