Cutaneous (Skin) Lymphoma Facts

July 13, 2024

This page was reviewed under our medical and editorial policy by Alex Herrera, M.D., associate professor, division of lymphoma, Department of Hematology & Hematopoietic Cell Transplantation, City of Hope® Cancer Center Duarte

Cutaneous lymphoma is a rare type of blood cancer, diagnosed in approximately 3,000 people in the United States each year. Also called skin lymphoma, this disease causes symptoms that appear on the skin, but it's not contagious and it isn't an infection.

What Is Cutaneous Lymphoma?

Cutaneous lymphoma is a type of non-Hodgkin lymphoma that affects the skin. 

Cutaneous lymphomas result in rashes, and sometimes tumors, which may be mistaken for other skin conditions. In a small number of people the disease may migrate to the lymph nodes or internal organs, causing serious complications. Skin lymphomas are rarer and behave very differently than systemic lymphomas, and usually require different treatments.

What Causes Skin Lymphoma?

When white blood cells called lymphocytes undergo genetic changes, they may develop into lymphoma cells. Lymphomas may form in any body parts that include lymphoid tissue, and when they develop in the skin, the resulting condition is known as cutaneous lymphoma. Researchers are unclear about what triggers these genetic changes to occur.

Types of Cutaneous Lymphoma

There are two main types of lymphocytes: B lymphocytes (B cells) and T lymphocytes (T cells). Cutaneous lymphomas are classified according to which cell type is involved. The subtypes are known as cutaneous T cell lymphoma and cutaneous B cell lymphoma.

Cutaneous T Cell Lymphoma

Cutaneous T cell lymphomas make up 75% to 80% of cutaneous lymphomas. Most CTCLs are indolent (slow-growing) and not life threatening.

The two most common CTCLs are listed below.

Mycosis Fungoides: Mycosis fungoides (MF) makes up about half of all cutaneous lymphoma cases. It tends to show up as flat, scaly, red lesions called patches; thicker, raised lesions called plaques; and raised lumps called tumors. In the early stages, MF may be easily confused with other skin problems, such as eczema, psoriasis, or dermatitis, making it difficult to diagnose.

Sezary syndrome: With this condition, patients develop a red rash that covers almost the entire body (called erythroderma). Unlike other types of CTCLs, which affect only the skin, Sezary syndrome affects both the skin and the blood. Lymphoma cells called Sezary cells are found in the skin and the blood, and lymph nodes are often enlarged. Sezary syndrome tends to grow and spread faster than mycosis fungoides. It is also more difficult to treat.

Rarer types of CTCL are listed below.
 
Lymphoproliferative disorders: This group includes primary cutaneous CD30-positive disease and its two main subtypes, lymphomatoid papulosis (LyP) and primary cutaneous anaplastic large cell lymphoma (C-ALCL); along with lymphomatoid papulosis and primary cutaneous anaplastic large cell lymphoma.
 
Subcutaneous panniculitis-like T cell lymphoma: This condition forms just under the skin and doesn't involve the lymph nodes.
 
Primary cutaneous aggressive epidermotropic CD8+ cytotoxic T cell lymphoma: This type of lymphoma typically causes red lesions on the skin.
 
Primary cutaneous Gamma/Delta T cell lymphoma: This cancer type typically causes large nodules on the skin, which may look like ulcers.
 
Primary cutaneous CD4+ small/medium sized pleomorphic T cell lymphoma: This condition may initially only appear as a single nodule that affects the patient's trunk or face.

Cutaneous B Cell Lymphomas

Cutaneous B cell lymphomas (CBCLs) are much rarer than cutaneous T cell lymphomas and make up about 20% to 25% of cutaneous lymphomas. More common systemic B cell lymphomas, such as Hodgkin lymphoma, can spread to the skin and mimic a CBCL.
 
The three main types of CBCL are:
 
Primary cutaneous marginal zone B cell lymphoma: This type of lymphoma may develop as red or pink bumps or tumors on the arms, torso or other areas.
 
Primary cutaneous follicle-center lymphoma: This condition may cause brownish-reddish bumps on the upper body.
 
Primary cutaneous diffuse large B cell lymphoma, leg type: This lymphoma type may lead to one or more nodules that appear on the legs, trunk or arms.

Cutaneous Lymphoma Risk Factors

Certain risk factors are associated with developing skin lymphoma, including those listed below. 

African American race: African-American patients are more likely to develop skin lymphoma than white patients. 

Immune system vulnerabilities: Patients who have weak immune systems may be more likely to develop cutaneous lymphoma. This may include individuals on immunosuppressant medications, those with acquired immunodeficiency syndrome (AIDS), and people infected with the Epstein-Barr virus. 

Male gender: Men are more commonly diagnosed with cutaneous lymphoma than women. 

Older age: Cutaneous lymphoma most frequently affects patients who are in their 50s or 60s, but the disease may occur among younger patients as well. 

Keep in mind that while risk factors may be useful in identifying high-risk individuals, they do not determine whether a person develops a disease. 

So far, large studies have not linked the environment, chemicals, or infections to developing cutaneous lymphoma.