title: Non-Hodgkin lymphoma in the periapical region of a mandibular canine.
abstract: BACKGROUND
  Images and clinical characteristics of some lesions may lead to misinterpretations between diseases of endodontic and non-endodontic origin. Non-Hodgkin lymphomas occur in extranodal sites and may arise primarily in the oral cavity or jaws.
  
  
  METHODS
  A case of lymphoma associated with the roots of teeth #21-23 in a 38-year-old woman is described. The patient sought dental care because of continuous discomfort at palpation of the periapical area of teeth #21-23, which had been treated endodontically. Radiographic and clinical exams revealed no inflammatory signs. The patient reported losing 24 pounds in the last 2 months. Intraoral examination revealed an expansion of the buccal surface, a solid hard mass, and normal mucosa color.
  
  
  RESULTS
  Conventional radiographs showed a diffuse bone radiolucent area, and cone-beam computed tomography images confirmed destruction of the buccal cortical bone, which was suggestive of malignancy. Incisional biopsy was performed, and microscopy showed a lymphoproliferative lesion of uncertain nature with pleomorphic lymphocyte-like round cells, hyperchromatic nuclei, and atypical mitoses. Immunohistochemistry was used to investigate the nature of these cells and the type of lymphoproliferative disorder, and results showed an area of diffuse large B-cell lymphoma.
  
  
  CONCLUSIONS
  Non-Hodgkin lymphoma should be part of the differential diagnosis of other jaw lesions such as apical periodontitis. The patient was treated with chemotherapy and did not report any abnormalities after 2 years of treatment.
authors.affiliation: Department of Oral Pathology, Federal University of Goiás, Goiânia, Goiás, Brazil. elismaur@odonto.ufg.br
authors.forename: Elismauro Francisco
authors.initials: EF
authors.lastname: Mendonça
authors.forename: Thiago Oliveira
authors.initials: TO
authors.lastname: Sousa
authors.forename: Carlos
authors.initials: C
authors.lastname: Estrela
mesh_terms: D000328:Adult; D016301:Alveolar Bone Loss / Q000175:diagnosis; D001706:Biopsy / Q000379:methods; D054893:Cone-Beam Computed Tomography / Q000379:methods; D003481:Cuspid / Q000473:pathology; D003937:Diagnosis, Differential; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D007150:Immunohistochemistry; D007180:Incisor / Q000473:pathology; D016403:Lymphoma, Large B-Cell, Diffuse / Q000175:diagnosis*; D008339:Mandibular Neoplasms / Q000175:diagnosis*; D010485:Periapical Periodontitis / Q000175:diagnosis*; D012390:Root Canal Therapy