Primary cutaneous follicle centre lymphoma

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.

Not Applicable
Module Rule
Module 6: PH12
Alternate Names
Crosti's disease
PCFCL, leg type
Primary cutaneous follicle center lymphoma
Reticulohistiocytoma of the dorsum
This is a tumor of neoplastic follicle centre cells, including centrocytes and variable numbers of centroblasts, with a follicular and diffuse growth pattern that generally presents on the head or trunk. This is the most common type of primary cutaneous B-cell lymphoma. It mainly affects adults.
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.

Disease 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.
Definitive Diagnostic Methods
Genetic testing
Histologic confirmation
Polymerase chain reaction (PCR)
Genetics Data
Amplification of C-REL gene
BCL2 rearrangements
BCL2 +/-
BCL6 +/-
CD10 +/-
Ig negative
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
C85.7 Other specified types of non-Hodgkin's lymphoma
Corresponding ICD-10-CM Codes (U.S. only)
C82.6 Cutaneous 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
Weigh loss (for no known reason)
Diagnostic Exams
CT (CAT) scan
Complete blood count (CBC)
Laparoscopy (rarely performed)
Laparotomy (rarely performed)
MRI (magnetic resonance imaging)
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
Incidence: most common primary cutaneous B-cell lymphoma (60%)
Sex: slight male predominance
Survival: 5 year survival over 95%