Primary cutaneous follicle centre lymphoma

ICD-O-3 Morphology

9597/3: Primary cutaneous follicle center lymphoma
Effective 2010 and later


for cases diagnosed 2010 and later

Primary Site(s)

C440-C449, C510-C512, C518-C519, C600-C602, C608-C609, C632
Most common sites of involvement: Cutaneous (skin) lymphoma, primarily on the scalp, forehead or trunk.

Abstractor Notes

(This code is effective for cases diagnosed 2010 and later. For cases diagnosed prior to 2010, see codes 9690/3 or 9709/3.)

Patients usually present with lesions on the scalp, forehead or trunk. Lesions on the leg have a less favorable prognosis. Regional lymph node involvement is uncommon, but possible.

Dissemination to distant nodes or other organs/tissue is rare and usually happens in the late stages of the disease.

Differences between follicle centre lymphoma and follicular lymphoma:
1. Follicle centre lymphoma is a cutaneous malignancy with only rare involvement of regional lymph nodes.
2. Follicular lymphoma commonly occurs in nodes and extranodal sites.

Note: If there is involvement of lymph node(s) that are not regional for the skin site involved, or involvement of bone marrow or organ(s), do not code histology primary cutaneous follicle centre cell lymphoma and do not code skin as the primary site. Code the histology to follicular lymphoma (See histology codes: 9690, 9691, 9695 or 9698).

Systemic therapy is only given for patients with very extensive cutaneous disease, extremely thick skin tumors, or with extracutaneous disease.

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

Module 6: PH12

Alternate Names

B-cell lymphoma, follicle type
Crosti's disease
Crosti lymphoma
Follicle cell lymphoma
PCFCL, leg type
Primary cutaneous follicle center lymphoma
Reticulohistiocytoma of the dorsum


Primary cutaneous follicle centre lymphoma (PCFCL) is a tumor of neoplastic follicle centre cells, including centrocytes and variable numbers of centroblasts, with a follicular, follicular and diffuse, or diffuse growth pattern. It generally presents on the head or trunk.

Definitive Diagnostic Methods

Genetic testing
Histologic confirmation
Polymerase chain reaction (PCR)

Genetics Data

BCL2 rearrangements
TR genes are clonally rearranged


BCL2 faint expression or negative
BCL6 expression
CD5 negative
CD10 expression
CD20 expression
CD43 negative
CD79Aa expression
FOXP1 negative


Radiation therapy

Transformations to

There are no known transformations

Transformations from

There are no known transformations

Corresponding ICD-9 Codes

202.0 Nodular lymphoma

Corresponding ICD-10 Codes

C82.7 Other types of follicular non-Hodgkin lymphoma

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

C82.6 Cutaneous follicle center lymphoma (effective October 01, 2015)
C82.5 Diffuse follicle center lymphoma (effective October 01, 2015)

Signs and Symptoms

Drenching night sweats
Fever (for no known reason)
Firm erythematous or violaceous plaques, nodules or tumors of varying sizes
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
CT (CAT) scan
Cytogenetic analysis
Flow cytometry
Laparoscopy (rarely performed)
Laparotomy (rarely performed)
Lymph node biopsy
PET (positron emission tomography) scan

Progression and Transformation

Cutaneous relapses noted in ~30% of patients
Recurrences usually proximate to the initial site of the tumor
Untreated skin lesions increase in size, rarely metastases to other sites

Epidemiology and Mortality

Age: 51 years median age
Sex: slight male predominance
Survival: 5 year survival over 95%


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 B-cell neoplasms
Pages: 282-284

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)