Contributed by Louis Samson, MD and Eduardo Zambrano, MD
A 3-month-old girl presented with a large right-hand mass that was present since birth, and a palpable right axillary lymph node. The patient underwent right hand amputation as well as right axillary lymphadenectomy in an outside institution.
A voluminous infiltrative ill-defined multinodular tan-white fleshy mass, significantly distorting the right-hand anatomy, was seen (Fig 1A - B).
Fig. 1. Right hand amputation specimen. External aspect of the tumor with marked deformation of the hand (A); cross-section of the specimen showing an ill-defined multinodular fleshy tan-white tumor (B).
Slides were received as a consultation and reviewed. Additional ancillary immunohistochemical stains were performed (BCL1, BCOR, SATB2). Microscopic examination revealed a well-circumscribed infiltrative lesion (Fig 2A) with prominent small arciform vessels (Fig 2C). Variably cellular sheets of round to plump elongated cells with focally vacuolated cytoplasm, and round to irregular nuclei with inconspicuous nucleoli were seen (Fig 2D). A slightly myxoid stroma was also appreciated. Numerous mitotic figures were noted. The examined lymph node was positive for metastatic disease (Fig 2B). Immunophenotypically, the neoplastic cells expressed BCOR, BCL1, and SATB2 in a nuclear location (Fig 3A - C).
Fig. 2. Microscopic aspect of the tumor. Well-circumscribed tumor in relation to a phalanx bone, H&E, 0.5X (A); Axillary lymph node with metastatic deposit, H&E, 10X (B); Sheets of small cells with prominent arciform capillaries, H&E, 10X (C); High magnification shows round to plump elongated cells with irregular nuclei and inconspicuous nucleoli, along with numerous mitoses, H&E, 40X (D).
Fig. 3. Immunohistochemical analysis. The neoplastic cells express diffuse and strong BCOR (A); BCL1 (B); and diffuse and weak SATB2 (C).