Search Database ICD-O-3 Code Lists

Name

Primary Mediastinal large B-cell lymphoma (PBML/PMBCL)

ICD-O-3 Morphology

9679/3: Mediastinal large B-cell lymphoma
Effective 2001 and later

Reportable

for cases diagnosed 1978 and later

Primary Site(s)

C379 , C383
Do not assign this histology just because the mediastinum is involved. Only assign this histology when the diagnosis is stated as “primary mediastinal."

See abstractor notes.

Coding Manual: Hematopoietic Coding Manual (PDF)

Abstractor Notes

Primary Mediastinal large B-cell lymphoma (PBML/PMBCL) 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)

Code the primary site to C379 (thymus) or C383 (mediastinum) based on the physician's statement.

Primary mediastinal large B-cell lymphoma typically arises in the anterior-superior mediastinum (thymic niche) with variable extension to the lung, pleura, or pericardium. Regional lymph nodes are frequently involved, most commonly the supraclavicular lymph nodes.

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

None

Alternate Names

Mediastinal diffuse large cell lymphoma with sclerosis (MLCLS)
Thymic large B-cell lymphoma

Definition

Primary mediastinal large B-cell lymphoma (PMBCL) is a mature aggressive B-cell lymphoma of putative thymic B-cell origin, arising in the anterior mediastinum with distinctive clinical, immunophenotypic, and molecular features. (WHO 5th ed)

Definitive Diagnostic Methods

Genetic testing
Histologic confirmation
Immunophenotyping

Genetics Data

CD274/PDCD1LG2 locus and/or rearrangement involving CIITA (C2TA)
JAK2/PDCD1LG2/CD274 locus at 9p24.1
PDCD1LG2 (also called PDL2)

Immunophenotyping

BOB1+ (expression/positive)
CD19+ (expression/positive)
CD20+ (expression/positive)
CD22+ (expression/positive)
CD30+ (expression/weakly positive) and heterogeneous
CD79a+ (expression/positive)
OCT2+ (expression/positive)
PAX5+ (expression/positive)
PU1+ (expression/positive)

Treatments

Chemotherapy
Radiation 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)

C83.8 Other types of diffuse non-Hodgkin lymphoma

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

C85.2_ Mediastinal (thymic) large B-cell lymphoma (effective October 01, 2015)
C85.2A Mediastinal (thymic) large B-cell lymphoma (effective October 01, 2024)

Signs and Symptoms

Drenching night sweats
Fatigue
Fever (for no known reason)
Localized anterosuperior mediastinal mass
Pain in the chest, abdomen, or bones (for no known reason)
Painless swelling in the lymph nodes
Skin rash or itchy skin
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: 35 years median age (occurs predominantly in young adults)
Incidence: 2-4% of non-Hodgkin lymphomas
Sex: M:F ratio: 1:2
Survival: beyond 2 years

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 lymphoma
Pages: Part B: 523-526

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