Peripheral T-cell lymphoma, NOS

ICD-O-2 Morphology

9702/3: Mature T-cell lymphoma, NOS
9703/3: T-zone lymphoma
9704/3: Lymphoepithelioid lymphoma
9707/3: Peripheral T-cell lymphoma, pleomorphic medium and large cell
Effective 1992 - 2000

ICD-O-3 Morphology

9702/3: Mature T-cell lymphoma, NOS
Effective 2001 and later


for cases diagnosed 1992 and later

Primary Site(s)

See Module 7
Most common sites of involvement: lymph nodes, skin and GI tract. Less common sites of involvement: lung, salivary gland, CNS

Abstractor Notes

Disease is often generalized with infiltrates in the bone marrow, liver, spleen, and extranodal tissue. Peripheral blood is sometimes involved, but leukemic presentation is uncommon.

The diagnosis of PTCL, NOS would be made ONLY when other specific entities have been excluded.

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.


Not Applicable

Module Rule


Alternate Names

Expanded mantle-zone T-cell lymphoma
Follicular T-cell lymphoma, NOS
Intrafollicular T-cell lymphoma
Lennert lymphoma
Lymphoepithelioid lymphoma
Mature T-cell lymphoma, NOS
Nodal peripheral T-cell lymphoma with T follicular helper phenotype
Paracortical nodular T-cell lymphoma
Perifollicular T-cell lymphoma, NOS
Peripheral T-cell lymphoma, large cell
Peripheral T-cell lymphoma, pleomorphic medium and large cell
Peripheral T-cell lymphoma, pleomorphic small cell
T-cell lymphoma, NOS
T-immunoblastic lymphoma
T-zone lymphoma


Peripheral T-cell lymphoma (PTCL), NOS, is a heterogeneous category of nodal and extranodal mature T-cell lymphomas that do not correspond to any of the specifically defined entities of mature T-cell lymphoma in the current classification.

Follicular T-cell lymphoma (FTCL) is a lymph node-based neoplasm of a T-follicular helper (TFH) cells, with a predominantly follicular growth pattern.

Lymphoepitheliod lymphoma (Lennert lymphoma) shows diffuse or (less commonly) interfollicular growth. Cytologically it consists predominantly of small cells with slight nuclear irregularities, numerous and sometimes confluent clusters of epithelioid histiocytes; and some larger more atypical, proliferating blasts. There can be admixed inflammatory cells and scattered Reed-Sternberg-like B cells (usually EBV-positive).

Nodal peripheral T-cell lymphoma with T follicular helper phenotype is recognized as a subset of the peripheral T-cell lymphoma classified as NOS has a T follicular helper (TFH) cell phenotype.

Definitive Diagnostic Methods

Genetic testing
Histologic confirmation

Genetics Data

TR genes are clonally rearranged


BCL6 expression
CD4 positive
CD5 downregulation
CD7 downregulation
CD8 positive (Lennert) and negative
CD10 expression
CD15 expression
CXCL13 expression
CXCR5 expression
ICOS expression
SAP expression


Hematologic Transplant and/or Endocrine Procedures
Hormone therapy

Transformations to

There are no known transformations

Transformations from

There are no known transformations

Corresponding ICD-9 Codes

202.7 Peripheral T-cell lymphoma

Corresponding ICD-10 Codes

C84.4 Peripheral T-cell lymphoma
C84.2 T-zone lymphoma
C84.3 Lymphoepithelioid lymphoma

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

C84.4 Peripheral T-cell lymphoma, not classified (effective October 01, 2015)

Signs and Symptoms

Drenching night sweats
Fever (for unknown reasons)
Hemophagocytic syndrome (rare)
Generalized lymphadenopathy (peripheral lymphadenopathy most common)
Pain in the chest, abdomen, or bones (for no known reason)
Weight loss (for no known reason)

Diagnostic Exams

Blood chemistry studies
CT (CAT) scan
Flow cytometry
PET (positron emission tomography) scan
Skin biopsy

Progression and Transformation

Frequent relapses of disease after treatment

Epidemiology and Mortality

Age: mostly occurs in adults
Incidence: 30% of peripheral T-cell lymphomas
Sex: male predominance
Survival: 20-30% 5 year survival


Swerdlow SH, Campo E, Harris NL, Jaffe ES, Pileri SA, Stein H, Thiele J (Eds):
WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues (Revised 4th edition)
IARC: Lyon 2017
Section: Mature T- and NK-cell neoplasms
Pages: 403-407, 411-412

International Classification of Diseases for Oncology, Third Edition, Second Revision. Geneva: World Health Organization, 2020.
Section: ICD-O-3.2 (2020) Morphological Codes

National Cancer Institute
Section: General Information About Adult Non-Hodgkin Lymphoma (NHL)