title: Fine-needle aspiration of a primary mediastinal large B-cell lymphoma: a case report with cytologic, histologic, and flow cytometric considerations.
abstract: Fine-needle aspiration (FNA) cytology and immunophenotyping by flow cytometry (FCM) are increasingly being used for diagnosing and subclassifying lymphoma in the REAL/WHO classification. Herein, we report a case of primary mediastinal large B-cell lymphoma (PMBL), a subtype of diffuse large B-cell lymphoma in the WHO classification, diagnosed by FNA cytology in conjunction with FCM. This, to our knowledge, has not previously been reported. A 57-yr-old woman presented with bilateral axillary lymphadenopathy and intermittent shortness of breath. CT scan revealed a 5-cm anterior mediastinal mass and mediastinal lymphadenopathy. Endoscopic ultrasound-guided FNA of a 4.5-cm subcarinal lymph node showed medium to large atypical lymphocytes with scant to moderate finely vacuolated cytoplasm. Nuclei were enlarged, cleaved, noncleaved, lobulated, and hyperchromatic. The background showed lymphoglandular bodies. Malignant large cell lymphoma was cytologically diagnosed. FCM, performed on a portion of the FNA specimen, demonstrated large B cells devoid of surface immunoglobulin expression, the characteristic immunophenotype of PMBL. The histologic diagnosis was PMBL. Touch-imprint cytology of the histologic specimen showed large cells with a narrow rim of clear cytoplasm and prominent outer cell border. Nuclear features were similar to the FNA specimen. In the presence of a mediastinal mass, FNA cytology in conjunction with FCM can effectively diagnose PMBL in the appropriate clinical setting.
authors.affiliation: Department of Pathology and Laboratory Medicine, Medical University of South Carolina, Charleston, South Carolina 29425, USA. hodars@musc.edu
authors.forename: Rana S
authors.initials: RS
authors.lastname: Hoda
authors.forename: Lee
authors.initials: L
authors.lastname: Picklesimer
authors.forename: Kimberly M
authors.initials: KM
authors.lastname: Green
authors.forename: Sally
authors.initials: S
authors.lastname: Self
mesh_terms: D015703:Antigens, CD / Q000032:analysis; D044963:Biopsy, Fine-Needle; D005260:Female; D005434:Flow Cytometry; D006801:Humans; D016393:Lymphoma, B-Cell / Q000473:pathology*; D016403:Lymphoma, Large B-Cell, Diffuse / Q000473:pathology; D008479:Mediastinal Neoplasms / Q000473:pathology*; D008875:Middle Aged
chemical_list: D015703:Antigens, CD