Fig. 4: Myofibroma.

Case #3. A multilobulated lesion with variation in cellularity (A, B). Note the hypocellular area of myoid cells (right) and the cellular area of ovoid cells (left) in B. A cellular area at the periphery, with tumor protruding into slit-like vessels (C). A cellular area of ovoid to epithelioid tumor cells and osteoclast-like giant cells (D). Case #6. Myoid morphology with prominent branching vessels (E) and a more cellular area at the periphery composed of ovoid tumor cells and osteoclast-like giant cells, protruding into a slit-like vessel (F). Note the transition of a myoid pseudochondroid area (upper right) into a more cellular area (lower left). Case #4. A myoid lesion with variation in cellularity and prominent branching vessels (G). A cellular nodule at the periphery with perivascular growth and osteclast-like giant cells (H).