History: A 31 y/o physician with a retroviral disease and associated immunodeficiency was found to have cervical lymphadenopathy. He had a chronic cough, but sputum had been negative for mycobacterium and PCP. There was no evidence of fungal or acid fast bacilli. No skin lesions were found and there was no history of previous neoplasia. Excisional lymph node biopsy was performed. The specimen was received in multiple fragments (Fig. 1)

Microscopically the normal lymph node architecture was replaced by a disordered vascular proliferation (Fig. 2). The cells were spindled and showed a diffuse fascicular pattern (More

History: A 28-year-old male presented with a left epigastric mass that had been present for ten years. During exploratory surgery, a 15 cm mass was excised from the greater omentum. It was gray-tan with a heterogeneous surface.

The tumor showed a peculiar trabecular growth pattern (Fig. 1), consisting of cohesive, small, polygonal to round blue cells, sometimes nested, with a prominent supporting desmoplastic stroma (Fig. 2). At the periphery of the tumor the tumor grew in nests and single files (Fig. 3). A subtle but substantial vascular network was seen (Fig. 3).… More

History: A 50-year-old female school teacher presented with a two year history of swelling of the right third toe. X-rays were read as being commensurate with a malignant tumor (Fig. 1), and an en-bloc resection of the third ray was performed. A hard, multinodular, tan-gray 5.0 cm mass was found to primarily involve the proximal phalangeal bone and adjacent soft tissue.

Microscopic sections showed the tumor to break out of bone and to involve surrounding tissues with extension up to the deep dermis (Fig. 2). The tumor displayed an osseous matrix consisting mostly of woven and… More

History: An otherwise healthy 44-year-old man presented with a three month history of a painless lump over his right hip. Aspiration of the mass was dry, yielding no fluid. Surgical excision was performed, finding a 4.0 cm, smooth, pink, slightly glistening soft tissue tumor just proximal to the greater trochanteric region. The tumor was solid, without hemorrhage or necrosis.

Microscopically, the mass was composed mostly of thick, hypocellular collagenous tissue (Fig. 1). It was well-circumbscribed and minimally associated with adjacent soft tissue (Fig. 2). Widely interspaced within the collagen were stellate to spindle-shaped cells resembling fibroblasts… More

History: A three month old baby boy presented to plastic surgery clinic with a purple-red tumor on his right eyelid. Radiographs taken prior to surgery demonstrated a well-defined soft tissue mass without calcification.

The resected specimen microscopically showed a mildly hyperkeratotic epidermis undermined by a cellular, vascular tumor (Fig. 1, 2). The tumor showed cyst-like spaces filled with blood, similar to changes seen in an aneurysmal bone cyst (Fig. 3). Much of the tumor was solid, supported by ectatic blood vessels, focally resembling a hemangiopericytoma vascular pattern (Fig. 4). Closer evaluation of… More