Perivascular Epithelioid Cell Neoplasms of the Head and Neck: Report of 3 Cases.
Anshu Bandhlish, Leon Barnes, Joseph Rabban, Jonathan McHugh. University of Michigan, Ann Arbor; University of Pittsburgh, PA; University of California San Francisco
Background: Perivascular epithelioid cell tumors (PEComa) are a family of related mesenchymal tumors including angiomyolipoma, lymphangiomyomatosis, lung clear cell sugar tumor and rare clear cell tumors in visceral and soft tissue sites. PEComas share overlapping histology, immunohistochemistry, and ultrastructure. They are characterized by a female preponderance, coexpression of melanocytic and smooth muscle markers and an intimate relationship with blood vessels. The growing interest in PEComas has led to increasing reports of these tumors in unusual locations. We describe a series of PEComas arising in the head and neck of 3 female patients and discuss the behavior of these distinctive tumors.
Design: H&E slides from 3 cases of head and neck PEComa from the consultation files of the authors were reviewed. All 3 cases were stained with melanocytic markers (HMB-45/Melan-A), S-100, muscle markers, vimentin, synaptophysin and pancytokeratin. Follow-up information was obtained from 2 cases.
Results: All patients were adult women with a wide age distribution (18, 26 and 71 years). 2 arose in the nasal cavity and 1 in the larynx. The signs and symptoms of PEComa of the larynx and the nasal cavity revealed no specificity and clinically the patients presented with hoarseness and mass effect, respectively. None had enlarged cervical lymph nodes. The histopathological features observed in all 3 tumors were large polygonal-epithelioid cells with clear or eosinophilic granular cytoplasm and distributed in a perivascular pattern. The nuclei were eccentric with vesicular chromatin and small nucleoli. Some cells contained a brown cytoplasmic pigment resembling melanin or lipofuscin. Immunohistochemistry confirmed coexpression of melanocytic markers (HMB-45 or Melan-A) and muscle markers (actin or calponin) in all. No infiltrative growth, cytologic atypia, necrosis or mitotic activity was observed. All underwent complete surgical resection and 2 patients with follow-up are free of disease at 2 and 8 years.
Conclusions: We describe 3 cases of head and neck PEComa arising in the larynx and the nasal cavity. Similar to other reports of PEComas in unusual locations, these neoplasms appear to follow a benign clinical course. Familiarity with PEComas will ensure its consideration in the differential diagnosis of tumors of the head and neck with a similar morphology. Additional cases with a longer follow-up will help in understanding the pathogenesis and behavior of PEComas.
Category: Head & Neck
Wednesday, March 2, 2011 9:30 AM
Poster Session V # 138, Wednesday Morning