title: Mediastinal mass in childhood T-cell acute lymphoblastic leukemia: significance and therapy response.
abstract: BACKGROUND
  T-cell acute lymphoblastic leukemia (T-ALL) accounts for approximately 10-13% of childhood ALL cases. Patients with T-ALL frequently present with unfavorable features at diagnosis and thus are considered to have a higher risk to relapse. Within the last 10 years, the previously dismal prognosis of this ALL subtype has been improved by intensified chemotherapy. However, 30-40% of patients still relapse, so that additional prognostic factors such as the local response of the mediastinal mass to therapy might allow defining the patients at risk in a better manner.
  
  
  METHODS
  A retrospective analysis of 116 Austrian patients with T-ALL was performed to assess whether an initial mediastinal mass (70/116) and its response to chemotherapy as measured by thoracic X-rays (32/70) might predict outcome.
  
  
  RESULTS
  Neither patients with a mediastinal tumor at the time of diagnosis nor patients with an incomplete response on day 35 or 70 of therapy had a worse prognosis, as compared with the group of patients with no initial tumor and complete regression on day 35 and 70.
  
  
  CONCLUSIONS
  We failed to show that in children with T-ALL residual mediastinal tumors are of prognostic relevance. This might suggest that incomplete local response is not necessarily an indication for treatment intensification such as local irradiation, second-look operation, or high-dose chemotherapy with bone marrow rescue. However, due to the relatively small number of patients analyzed, our results have to be validated prospectively on a larger cohort of patients in future clinical trials.
authors.affiliation: St. Anna Children's Hospital, Kinderspitalgasse 6, A-1090 Vienna, Austria.
authors.forename: Andishe
authors.initials: A
authors.lastname: Attarbaschi
authors.forename: Georg
authors.initials: G
authors.lastname: Mann
authors.forename: Michael
authors.initials: M
authors.lastname: Dworzak
authors.forename: Peter
authors.initials: P
authors.lastname: Wiesbauer
authors.forename: Martin
authors.initials: M
authors.lastname: Schrappe
authors.forename: Helmut
authors.initials: H
authors.lastname: Gadner
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D018572:Disease-Free Survival; D005260:Female; D006801:Humans; D007223:Infant; D015459:Leukemia-Lymphoma, Adult T-Cell / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology; D008297:Male; D008479:Mediastinal Neoplasms / Q000000981:diagnostic imaging / Q000188:drug therapy* / Q000473:pathology; D011379:Prognosis; D011859:Radiography; D012008:Recurrence; D012189:Retrospective Studies; D016896:Treatment Outcome