Search Database ICD-O-3 Code Lists

Name

Mediastinal grey-zone lymphoma (MGZL)

ICD-O-3 Morphology

9596/3: Composite Hodgkin and non-Hodgkin, NOS
Effective 2001 and later

Reportable

for cases diagnosed 1978 and later

Primary Site(s)

C770-C779
Lymph nodes (C770-C779) are the usual primary sites; however, involvement in other sites is possible.
Common metastatic sites include the bone marrow/peripheral blood, and liver.
Spleen involvement is common due to dissemination of disease

Assign C779 if specific primary site cannot be determined.

See abstractor notes

Coding Manual: Hematopoietic Coding Manual (PDF)

Abstractor Notes

Mediastinal grey-zone lymphoma (MGZL) is part of the Mature B-cell neoplasms lineage table in the WHO 5th edition of Hematolymphoid Tumors. (See Appendix B in the Hematopoietic Manual, Table B15)

Prior to 2010, the term for this code was composite Hodgkin and non-Hodgkin lymphoma. In the 2008 WHO, the term used to describe this same disease is B-cell lymphoma, unclassifiable, with features indeterminate between diffuse large B-cell lymphoma and classical Hodgkin lymphoma. The change in terminology reflects current clinical knowledge that the non-Hodgkin portion of this lymphoma has proven to be a B-cell immunophenotype.

This code also represents the newest terminology, which is mediastinal grey zone lymphoma, which typically presents as a localized anterior mediastinal mass (C771), with frequent involvement of the supraclavicular lymph nodes and invasion of the lung or pleura. Dissemination below the diaphragm and to other extranodal sites is uncommon.

Rare cases without anterior mediastinal involvement are referred to as grey zone lymphoma with primary extramediastinal presentation (PEMGZL). Such cases present generally as disseminated disease with lymph node, spleen, liver, and/or bone marrow involvement.

Diagnostic Confirmation

This histology can be determined by positive histology (including peripheral blood) with or without genetics and/or immunophenotyping. Review the Definitive Diagnostic Methods, Immunophenotyping and Genetics Data sections below, and the instructions in the Hematopoietic Manual for further guidance on assigning Diagnostic confirmation.

Module Rule

M5

Alternate Names

B-cell lymphoma, unclassifiable, with features intermediate between diffuse large B-cell lymphoma and classic Hodgkin lymphoma
Composite Hodgkin and non-Hodgkin lymphoma
Grey zone lymphoma with primary extramediastinal presentation (PEMGZL)

Definition

Mediastinal grey zone lymphoma (MGZL) is a B-cell lymphoma with overlapping clinical, morphological, immunophenotypic, and molecular features between primary mediastinal B-cell lymphoma (PMBCL) and classic Hodgkin lymphoma (CHL), particularly nodular sclerosis CHL (NSCHL). (WHO 5th edition)

Definitive Diagnostic Methods

Cytogenetics
Genetic testing
Histologic confirmation
Immunohistochemistry
Immunophenotyping

Genetics Data

(JAK2/CD274/PDCD1LG2) and 16p13.13 (CIITA [C2TA]
PDCD1LG2 (also called PDL2) loci at 9p24.1
MYC gains
9p24.1 gains/amplifications

Immunophenotyping

BOB1+ (expression/positive)
CD19+ (expression/positive)
CD20+ (expression/positive)
CD79a+ (expression/positive)
OCT2+ (expression/positive)
PAX5+ (expression/positive)

Treatments

Chemotherapy
Hematologic Transplant and/or Endocrine Procedures
Hormone therapy

Transformations to

There are no known transformations

Transformations from

There are no known transformations

Same Primaries

Corresponding ICD-10 Codes (Cause of Death codes only)

C83.3 Non-Hodgkin lymphoma large cell (diffuse)

Corresponding ICD-10-CM Codes (U.S. only)

C83.3_ Diffuse large B-cell lymphoma (effective October 01, 2015)
C83.3A Diffuse large B-cell lymphoma, in remission (effective October 01, 2024)

Signs and Symptoms

Drenching night sweats
Fatigue
Fever (for no known reason)
Pain in the chest, abdomen, or bones (for no known reason)
Painless swelling in the lymph nodes
Respiratory distress
Skin rash or itchy skin
Superior vena cava syndrome
Weight loss (for no known reason)

Diagnostic Exams

Blood chemistry studies
Bone marrow aspiration and biopsy
CT (CAT) scan
Cytogenetic analysis
Flow cytometry
Immunohistochemistry
Immunophenotyping
Laparoscopy (rarely performed)
Laparotomy (rarely performed)
Lymph node biopsy
PET (positron emission tomography) scan

Progression and Transformation

None

Epidemiology and Mortality

Age: 20-40 years most common (13-70 years range)
Sex: male predominance

Sources

WHO Classification of Tumours Editorial Board. Haematolymphoid tumours. Lyon (France): International Agency for Research on Cancer; 2024. (WHO classification of tumours series, 5th ed.; vol. 11). https://publications.iarc.who.int/637.
Section: Large B-cell lymphomas
Pages: Part B: 527-529

International Classification of Diseases for Oncology, 3rd edition (including revisions). Geneva: World Health Organization, 2001, 2011, 2020.
Section: ICD-O-3.2 (2020) Morphological Codes
Pages: http://www.iacr.com.fr/index.php?option=com_content&view=category&layout=blog&id=100&Itemid=577

PDQ® Adult Treatment Editorial Board. PDQ Aggressive B-Cell Non-Hodgkin Lymphoma Treatment. Bethesda, MD: National Cancer Institute. Updated <02/24/2025>. Available at: https://www.cancer.gov/types/lymphoma/hp/aggressive-b-cell-lymphoma-treatment-pdq. Accessed <03/20/2025>.
Section: Aggressive B-Cell Non-Hodgkin Lymphoma Treatment (PDQ®)–Health Professional Version
Pages: https://www.cancer.gov/types/lymphoma/hp/aggressive-b-cell-lymphoma-treatment-pdq
Glossary