title: Role of computed tomography on large B-cell non-Hodgkin's lymphoma follow-up and the risk of radiation-induced neoplasm: A retrospective cohort study.
abstract: BACKGROUND
  To evaluate the role of surveillance computed tomography (CT) in detection of tumor relapse after complete remission for large-cell lymphoma and to estimate the cancer risk related to those examinations.
  
  
  METHODS
  We retrospectively identified the cases of large-cell lymphoma diagnosed at our institution during a fifteen years period. We extracted from charts the information needed. Agreement between clinical and radiological evaluation for relapse detection was determined with index kappa and McNemar tests. We analysed the surveillance CT examinations performed to the patients in complete remission with no recurrence during the follow-up period and we estimated the life attributable risk (LAR) of radiation-induced cancer above base line using the approach of the Biological Effects of Ionizing Radiation (BEIR) VII.
  
  
  RESULTS
  184 patients with biopsy confirmed large-cell lymphoma were included. Complete remission was attained in 125 patients. After a median follow-up of 93.73 months, 97 of them remain in remission. Relapse was confirmed in 28 patients; only 3 of them were asymptomatic. Kappa and McNemar analyses revealed good agreement for diagnosis of recurrence and significant difference for exclusion of relapse. Patients in remission received a median of 6 surveillance CT examinations. Fifty-seven patients had total cumulative doses greater than 100mSv. The mean increase in estimated radiation-induced cancer risk was 0.5%.
  
  
  CONCLUSIONS
  Our results suggest that periodic CT examinations have a limited role in detecting relapse in large-cell lymphoma as the clinical surveillance dictates the patient management.
authors: Department of Radiology, Hospital Clínico San Carlos, Profesor Martín Lagos s/n, 28040 Madrid, Spain. Electronic address: lu_rx@hotmail.com.
authors: Lucía
authors: L
authors: Graña
authors: Medical Physics Group, Department of Radiology, Complutense University, Plaza Ramón y Cajal s/n, 28040 Madrid, Spain. Electronic address: calzado@med.ucm.es.
authors: Alfonso
authors: A
authors: Calzado
authors: Department of Radiology, Hospital Clínico San Carlos, Profesor Martín Lagos s/n, 28040 Madrid, Spain. Electronic address: phmaula@gmail.com.
authors: Paula
authors: P
authors: Hernández
authors: Department of Radiology, Hospital Clínico San Carlos, Profesor Martín Lagos s/n, 28040 Madrid, Spain. Electronic address: rrodriguez.hcsc@salud.madrid.org.
authors: Ricardo
authors: R
authors: Rodríguez
mesh_terms: D001402:B-Lymphocytes; D015331:Cohort Studies; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008228:Lymphoma, Non-Hodgkin / Q000000981:diagnostic imaging* / Q000453:epidemiology*; D008297:Male; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000175:diagnosis; D009381:Neoplasms, Radiation-Induced / Q000453:epidemiology*; D012189:Retrospective Studies; D012306:Risk; D013030:Spain / Q000453:epidemiology; D014057:Tomography, X-Ray Computed / Q000379:methods*
keywords: Cancer risk; Computed tomography; Lymphoma; Relapse; Surveillance