The Skin Itch You Can’t Ignore: Understanding Cutaneous Lymphoma

*This article was written in collaboration with our partners at the Cutaneous Lymphoma Foundation.

When most people think of blood cancers, such as lymphoma, they think of cancer that affects, as the name implies, the blood. But for those diagnosed with cutaneous lymphomas, the first signs often appear on the skin.

Lymphomas that arise in tissues or organs outside of the lymphatic system (tissues and organs that produce, store, and carry white blood cells) are called extranodal lymphomas. Extranodal lymphomas that arise and manifest in the skin are called cutaneous lymphomas. When lymphomas start in the skin and there is no evidence of disease outside of the skin, they are called primary cutaneous lymphomas. There are two types of primary cutaneous lymphomas depending on the type of lymphocytes involved, T-cells or B-cells. Each type can have different signs and symptoms, disease course, and prognosis.

Cutaneous lymphomas are rare and often misunderstood, frequently misdiagnosed as eczema, psoriasis, or another common skin condition. Yet, for those living with it, cutaneous lymphoma can be life-changing—not just because of the visible symptoms, but also due to the persistent itch and emotional toll it can take.

Cutaneous T-cell Lymphoma (CTCL)

CTCL is the most common kind of cutaneous lymphoma. It begins in T cells that are found in the skin, and symptoms often include dry, itchy skin (which can be severe), red patches or rashes, and swollen lymph nodes. Most people with CTCL only have skin symptoms, and some may never develop more serious disease. Others may progress quickly, with the cancer spreading to lymph nodes or internal organs. CTCL usually affects men more than women and is most common in people in their 50s and 60s.

Common Types of CTCL:

• Mycosis Fungoides (MF): The most common type of CTCL. It can appear as patches, plaques, or tumors on the skin.
• Sézary Syndrome (SS): A more serious form where cancer cells are found in the blood. It causes widespread red, itchy skin.

Many factors are considered to identify the most appropriate treatment for each patient, including the extent of skin involvement, the type of skin lesion, and whether the cancer has spread to the lymph nodes or other internal organs. Skin-directed therapies, such as topical treatments (medications applied to the skin), local radiation, and ultraviolet light, are generally used for earlier-stage disease and are typically useful for patches and limited plaques. While systemic treatment may be used in more advanced stage disease and in those with earlier stage diseases in whom skin-directed therapies did not help, were not tolerated, or are not available.

Cutaneous B-cell Lymphoma (CBCL)

CBCLs start in B cells in the skin and are usually slow-growing. It can appear as red bumps, lumps, or nodules that may be smooth and slightly raised. Although the disease often comes back in new spots on the skin, it usually doesn’t spread to other parts of the body. That means the outlook is generally good. CBCL makes up about 20–25% of all primary cutaneous lymphomas, while CTCL makes up 75–80%.

Types of CBCL:

• Primary Cutaneous Follicle Center Lymphoma: Grows slowly and often shows up on the head, neck, or upper body as red-brown bumps or nodules.
• Primary Cutaneous Marginal Zone B-Cell Lymphoma: Another slow-growing type, causing pink or red lesions, mostly on the torso or arms.
• Primary Cutaneous Diffuse Large B-Cell Lymphoma, Leg Type: A faster-growing type that shows up as one or more tumors on the legs, arms, or torso.
• Other Rare Types: Includes several rare and aggressive forms that often appear on the head, body, or limbs.

Treatment options for cutaneous B-cell lymphoma depend on the type of CBCL, the patient’s symptoms and overall health, and the stage of the disease. For slow-growing types, options include watchful waiting, radiation, or surgery. For more aggressive types, radiation with or without chemotherapy is often used. Clinical trials may also be an option. Although treatment can lead to remission, relapses are common.

Challenges with Cutaneous Lymphomas

One of the most challenging things about cutaneous lymphomas is reaching a correct diagnosis. A definitive diagnosis will help inform treatment decisions and potentially yield better outcomes. One of the key concepts for patients and their caregivers to understand is that a clear diagnosis may take time; in the case of cutaneous lymphoma, a definitive diagnosis sometimes takes years. The best approach for patients is to collaborate and work with their physicians. By definition, all cutaneous lymphomas present skin-related symptoms. When a patient presents with skin lesions, their physician will work to differentiate whether the lesions are the result of a reactive process versus a lymphoma of the skin. Since reactive processes and other types of inflammation can trigger symptoms similar to those of cutaneous lymphomas, evaluation by a provider with experience in diagnosing skin lymphoma is important if skin lymphoma is suspected. In many cases, test results (such as skin biopsy) may not initially be conclusive, which means they cannot clearly differentiate between lymphoma versus other skin reactions.

Skin biopsies over time are often needed to obtain a proper diagnosis. Whenever a biopsy is taken, a patient’s doctor, in conjunction with a pathologist, will work together to try to obtain the most accurate diagnosis. A definitive diagnosis cannot be obtained without a biopsy, and multiple biopsies are often necessary to confirm the diagnosis of cutaneous lymphoma. It is very important to confirm any diagnosis of cutaneous lymphoma by a specialized type of pathologist – dermatopathologist or a hematopathologist – who has expertise in diagnosing cutaneous lymphomas.

Lymphoma Research Foundation and Cutaneous Lymphoma Foundation’s Partnership

In 2024, the Lymphoma Research Foundation joined forces with the Cutaneous Lymphoma Foundation (CLFOUNDATION) to launch a powerful new partnership with a shared mission: to improve the lives of everyone affected by T-cell lymphoma. This collaboration was born out of a pressing need—despite progress in other areas of lymphoma research, advancements in understanding and treating T-cell lymphomas have significantly lagged behind those made for B-cell lymphomas. The challenges posed by the rarity of T-cell lymphomas are compounded by the smaller number of scientists and clinicians pursuing the study of these lymphoma subtypes and scarcity of funds available for related clinical trials. This situation presented the need for a platform to foster scientific collaboration to advance the field and meet the unique needs of this patient population.

The Lymphoma Research Foundation facilitates several disease-specific global consortia and scientific workshops, convening scientific experts from around the world to share research findings and collaborate, with a goal of advancing the most promising lymphoma and CLL research. In partnership with the Cutaneous Lymphoma Foundation, the Lymphoma Research Foundation will host the T-cell Lymphomas International Scientific Workshop in May 2025. The workshop will convene the world’s leading T-cell lymphoma experts to discuss the latest research findings, plan future studies, foster collaboration within the research community, and create a research agenda, which in turn could prioritize T-cell lymphoma research and improve outcomes.

In addition to scientific collaboration, the Foundations will continue working together to provide free education and support services nationwide to T-cell lymphoma patients and their families.