title: Mediastinal Gray Zone Lymphoma: A Wider Category Than We Think?
abstract: OBJECTIVE
  To identify aggressively behaving classical Hodgkin lymphoma (CHL) of mediastinum and primary mediastinal B-cell lymphoma (PMBCL) and to classify them as mediastinal gray zone lymphoma(MGZL) and to define a minimum immunopanel for the diagnosis of MGZL.
  
  
  METHODS
  Ninety-two mediastinal B-cell lymphomas were reviewed with a wide immunopanel and were classified as CHL, PMBCL, or MGZL. CHL with an expression of 3 or 4 transcription factors performed worse, and hence the CHL with ≥3 transcription factors were classified as MGZL-CHL. In PMBCL, the cases with a weak or negative CD20 and positive CD15 as well as those cases showing cyclin E positivity with a negative or focal LCA and any one of the transcription factors were classified as MGZL-PMBCL.
  
  
  RESULTS
  The MGZL cases expanded from 9 to 28 cases after using an extended immunopanel. CHL and PMBCL had a disease-free survival rate of 86.8% and 69.2% and an overall survival rate of 97.4% and 80.8%, respectively. MGZL-CHL and MGZL-PMBCL had a disease-free survival rate of 33% and 40% and an overall survival rate of 66.7% and 60%, respectively.
  
  
  CONCLUSIONS
  Thus, the MGZL may be a wider category than we think and hence the use of a wide immunopanel is recommended to identify the aggressively behaving mediastinal B-cell lymphomas.
authors.affiliation: Department of Pathology, Tata Memorial Hospital, Mumbai, India.
authors.forename: Anuj
authors.initials: A
authors.lastname: Verma
authors.affiliation: Department of Pathology, Tata Memorial Hospital, Mumbai, India tanujashet5@gmail.com.
authors.forename: Tanuja
authors.initials: T
authors.lastname: Shet
authors.affiliation: Department of Pathology, Tata Memorial Hospital, Mumbai, India.
authors.forename: Sridhar
authors.initials: S
authors.lastname: Epari
authors.affiliation: Department of Pathology, Tata Memorial Hospital, Mumbai, India.
authors.forename: Manjudevi
authors.initials: M
authors.lastname: Gupta
authors.affiliation: Department of Pathology, Tata Memorial Hospital, Mumbai, India.
authors.forename: Sumeet
authors.initials: S
authors.lastname: Gujral
authors.affiliation: Department of Radiation Oncology, Tata Memorial Hospital, Mumbai, India.
authors.forename: Nehal
authors.initials: N
authors.lastname: Khanna
authors.affiliation: Department of Radiation Oncology, Tata Memorial Hospital, Mumbai, India.
authors.forename: Siddhartha
authors.initials: S
authors.lastname: Laskar
authors.affiliation: Department of Medical Oncology, Tata Memorial Hospital, Mumbai, India.
authors.forename: Manju
authors.initials: M
authors.lastname: Sengar
authors.affiliation: Department of Pediatric Oncology, Tata Memorial Hospital, Mumbai, India.
authors.forename: Brijesh
authors.initials: B
authors.lastname: Arora
authors.affiliation: Department of Medical Oncology, Tata Memorial Hospital, Mumbai, India.
authors.forename: Hari
authors.initials: H
authors.lastname: Menon
authors.affiliation: Department of Medical Oncology, Tata Memorial Hospital, Mumbai, India.
authors.forename: Shripad
authors.initials: S
authors.lastname: Banavali
mesh_terms: D014408:Biomarkers, Tumor / Q000032:analysis; D018572:Disease-Free Survival; D006801:Humans; D007150:Immunohistochemistry; D016130:Immunophenotyping; D053208:Kaplan-Meier Estimate; D016393:Lymphoma, B-Cell / Q000145:classification* / Q000175:diagnosis* / Q000401:mortality; D008479:Mediastinal Neoplasms / Q000145:classification* / Q000175:diagnosis* / Q000401:mortality; D016016:Proportional Hazards Models
chemical_list: D014408:Biomarkers, Tumor
keywords: Hodgkin lymphoma; gray zone lymphoma; mediastinum