title: Metastatic pleomorphic adenoma to the supraspinatus muscle: a case report and review of a rare aggressive clinical entity.
abstract: We report a case of a 65-year-old female with a recurrent right parotid pleomorphic adenoma (PA) 24 years after initial surgical excision. Positron-emission tomography (PET) and computed tomography (CT) demonstrated an unusual suspicious FDG-avid erosive rim enhancing mass centered in the right supraspinatus muscle. Cytology from CT-guided aspiration of the mass was consistent with a histologically benign PA, and the patient was diagnosed with metastatic pleomorphic adenoma (MPA). The patient later developed diffuse pulmonary metastases and died within 3 months. MPA, although rare, is recognised as a potentially lethal malignant complication of recurrent or longstanding benign PA. As no biochemical or genetic parameters are predictive of malignant change, patients presenting with recurrent PA should be considered for screening for metastatic disease.
authors.affiliation: Department of Radiology, Beaumont Hospital, Dublin, Ireland.
authors.forename: James G
authors.initials: JG
authors.lastname: McGarry
authors.affiliation: Department of Pathology, Beaumont Hospital, Dublin, Ireland.
authors.forename: Maeve
authors.initials: M
authors.lastname: Redmond
authors.affiliation: Department of Radiology, Beaumont Hospital, Dublin, Ireland.
authors.forename: John B
authors.initials: JB
authors.lastname: Tuffy
authors.affiliation: Blackrock Clinic Nuclear Medicine PET CT centre, Blackrock, Co. Dublin, Ireland.
authors.forename: Lorraine
authors.initials: L
authors.lastname: Wilson
authors.affiliation: Department of Radiology, Beaumont Hospital, Dublin, Ireland.
authors.forename: Seamus
authors.initials: S
authors.lastname: Looby
mesh_terms: D008949:Adenoma, Pleomorphic / Q000209:etiology / Q000473:pathology* / Q000601:surgery; D000368:Aged; D064131:Back Muscles / Q000473:pathology*; D003937:Diagnosis, Differential; D003952:Diagnostic Imaging; D005260:Female; D006801:Humans; D008175:Lung Neoplasms / Q000556:secondary*; D019042:Muscle Neoplasms / Q000175:diagnosis / Q000556:secondary*; D010307:Parotid Neoplasms / Q000209:etiology / Q000473:pathology* / Q000601:surgery; D011379:Prognosis
keywords: Pleomorphic adenoma; metastatic; parotid tumours; rotator cuff metastasis