title: PEComa of the nasal cavity with worrisome histologic features and benign behavior: a case report.
abstract: OBJECTIVE
  PEComas (perivascular epithelioid cell tumors) are a family of neoplastic lesions that share overlapping ultrastructure and morphological and immunohistochemical appearance and include angiomyolipoma, lymphangioleiomyomatosis, and clear cell "sugar" tumor of the lung, as well as similar tumors that occur in a variety of visceral, cutaneous, and soft tissue sites throughout the body.
  
  
  METHODS
  A 40-year-old woman came to medical attention because of epistaxis and because of unilateral nasal obstruction of 3 months' duration. Endoscopic examination revealed a well-demarcated exophytic lesion attached to the anterior portion of the middle turbinate.
  
  
  RESULTS
  The lesion was superficially located, and therefore amenable to complete surgical excision. Seven years after surgery, the patient is alive and well, without evidence of local recurrence or metastastic disease. Based on morphological and immunohistochemical appearance, a diagnosis of PEComa with worrisome histologic features was rendered.
  
  
  CONCLUSIONS
  In the present study, we describe a PEComa that occurred in the nasal cavity and discuss the behavior of this entity. The importance of recognizing this disease will ensure its consideration in the differential diagnosis of tumors of the head that have similar morphological features. The histogenesis of PEComa still remains elusive, and collection of additional cases with a prolonged follow-up will be important in accurately determining the behavior of these distinctive tumors.
authors.affiliation: Institute of Otorhinolaryngology, Department of Surgery, Maggiore Hospital, Bologna, Italy.
authors.forename: Corso
authors.initials: C
authors.lastname: Bocciolini
authors.affiliation: Institute of Pathology, Department of Oncology, Maggiore Hospital, Bologna, Italy.
authors.forename: Adele
authors.initials: A
authors.lastname: Fornelli
authors.affiliation: Institute of Pathology, Department of Oncology, Maggiore Hospital, Bologna, Italy.
authors.forename: Gian Piero
authors.initials: GP
authors.lastname: Casadei
authors.affiliation: Institute of Pathology, Department of Oncology, Bellaria Hospital, Bologna, Italy.
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Cattani
authors.affiliation: Institute of Otorhinolaryngology, Department of Surgery, Maggiore Hospital, Bologna, Italy.
authors.forename: Danilo
authors.initials: D
authors.lastname: Dall'Olio
mesh_terms: D000328:Adult; D001706:Biopsy; D018450:Disease Progression; D004724:Endoscopy; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D009296:Nasal Cavity / Q000473:pathology*; D009367:Neoplasm Staging; D009669:Nose Neoplasms / Q000473:pathology*; D054973:Perivascular Epithelioid Cell Neoplasms / Q000473:pathology*