title: Malignant perivascular epithelioid cell tumor of mesentery with lymph node involvement: a case report and review of literature.
abstract: Perivascular epithelioid cell tumor (PEComa) is a rare but distinct mesenchymal neoplasm composed of histologically and immunohistochemically unique perivascular epithelioid cells. Due to its relative rarity, little is known about the histogenesis and prognostic factors of this tumor. We describe a case of unusual mesenteric PEComa in a 38-year-old female patient with regional lymph node involvement. Histologically, the tumor was composed of sheet of epithelioid cells with abundant clear or eosinophillic cytoplasms. Extensive coagulative necrosis and a few mitotic figures (2/50 high power field) could be found in tumor. The epithelioid tumor cells were diffusely positive for HMB-45, Melan-A, and focally positive for calponin. One of enlarged mesenteric lymph nodes was observed to be involved by tumor. A diagnosis of malignant mesenteric PEComa with lymph node involvement was made. The patient received chemotherapy after total resection of tumor and segmental resection of involved jejunum. There was no sign of recurrence of tumor found in period of 6-month regular follow-up after chemotherapy. To our knowledge, this is the first case of malignant PEComa in mesentery accompanied with regional lymph node involvement. The literature on this rare tumor is reviewed and diagnostic criteria of malignant PEComa are discussed.
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authors.affiliation: Department of Pathology, The First Affiliated Hospital, Guangzhou Medical University, Guangzhou, China.
authors.forename: Xinge
authors.initials: X
authors.lastname: Fu
authors.forename: Ju-hong
authors.initials: JH
authors.lastname: Jiang
authors.forename: Xia
authors.initials: X
authors.lastname: Gu
authors.forename: Zhi
authors.initials: Z
authors.lastname: Li
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis; D017024:Chemotherapy, Adjuvant; D013505:Digestive System Surgical Procedures; D005260:Female; D006801:Humans; D007150:Immunohistochemistry; D007580:Jejunal Neoplasms / Q000737:chemistry / Q000473:pathology* / Q000628:therapy; D008198:Lymph Nodes / Q000473:pathology*; D008207:Lymphatic Metastasis; D008297:Male; D008643:Mesentery / Q000737:chemistry / Q000473:pathology*; D008875:Middle Aged; D008938:Mitosis; D009336:Necrosis; D054973:Perivascular Epithelioid Cell Neoplasms / Q000737:chemistry / Q000556:secondary* / Q000628:therapy; D011237:Predictive Value of Tests; D013997:Time Factors; D014057:Tomography, X-Ray Computed; D016896:Treatment Outcome
chemical_list: D014408:Biomarkers, Tumor