title: Fine needle aspiration biopsy of precursor B-cell lymphoblastic lymphoma presenting as a sacral mass. A case report.
abstract: BACKGROUND
  Lymphoblastic lymphoma (LBL) is a high grade, aggressive neoplasm, usually presenting in children and young adults. Precursor B-cell LBL is uncommon and may present with cutaneous or, less likely, bone lesions. This case represents the first reported presentation of LBL as a sacral lesion and was only the second fine needle aspiration biopsy (FNAB) of LBL presenting as a bony mass.
  
  
  METHODS
  A 50-year-old man presented with a 3-month history of a 7 x 5 x 4-cm mass in the sacral region. The mass was radiologically described as an expansile one with lytic bone destruction. Diagnosis of a chordoma was radiologically favored. Computed tomography (CT)-guided FNAB, with flow cytometry and cytochemical staining, was used to make the diagnosis of precursor B-cell LBL.
  
  
  CONCLUSIONS
  FNAB was instrumental in reaching this unusual diagnosis in a patient who was free of disease after chemotherapy.
authors.affiliation: Department of Pathology, Saint Louis University, St. Louis, Missouri, USA.
authors.forename: Amobi M
authors.initials: AM
authors.lastname: Ezenekwe
authors.forename: Brian T
authors.initials: BT
authors.lastname: Collins
authors.forename: T Brent
authors.initials: TB
authors.lastname: Ponder
mesh_terms: D015703:Antigens, CD / Q000096:biosynthesis; D001402:B-Lymphocytes / Q000378:metabolism / Q000473:pathology; D014408:Biomarkers, Tumor / Q000096:biosynthesis; D044963:Biopsy, Fine-Needle; D001859:Bone Neoplasms / Q000378:metabolism / Q000473:pathology*; D002817:Chordoma / Q000473:pathology; D003937:Diagnosis, Differential; D005434:Flow Cytometry; D006801:Humans; D016393:Lymphoma, B-Cell / Q000378:metabolism / Q000473:pathology*; D008297:Male; D008875:Middle Aged; D054198:Precursor Cell Lymphoblastic Leukemia-Lymphoma / Q000378:metabolism / Q000473:pathology*; D011237:Predictive Value of Tests; D015203:Reproducibility of Results; D012447:Sacrum / Q000473:pathology*; D013234:Stem Cells / Q000378:metabolism / Q000473:pathology
chemical_list: D015703:Antigens, CD; D014408:Biomarkers, Tumor