Lymphoma is a type of cancer that starts in immune cells called lymphocytes. When lymphoma affects the skin, it may cause a rash that appears as one or more scaly, reddish-to-purple patches, plaques, or nodules.
A lymphoma rash, such as mycosis fungoides (MF), can be easy to confuse with other skin conditions, such as psoriasis or eczema, which can cause similar symptoms. A person may also experience other symptoms, and these can help doctors make the correct diagnosis.
Early diagnosis and treatment are vital, and the combination of approaches will depend on the type of lymphoma a person has. In this article, learn more about lymphoma rashes.
A lymphoma rash is not a term that doctors usually use, but some people use the term to describe skin-related symptoms of lymphoma.
Skin rashes are uncommon symptoms of Hodgkin lymphoma, but they may result more often from other types of lymphoma that start in T or B cells.
The American Cancer Society note that nearly half of all skin lymphomas are MF. The most common type of cutaneous T cell lymphoma, MF occurs when cancerous T cells are present in the skin with a characteristic presentation of patches, plaques, and sometimes tumor-like lesions.
The most common sign of MF is a rash consisting of one or more scaly, inflamed patches of skin. These patches are generally itchy, and they are easiest to recognize in a bathing suit distribution, commonly appearing on the buttocks and thighs.
Over time, the rash may become more severe and spread to other areas. The affected skin may get thick and hard, and form raised plaques. The plaques may darken and possibly bleed. Some form tumor-like raised lesions.
Other people with MF may experience a very dry and itchy redness over a majority of their skin, and this can indicate Sezary syndrome.
Doctors consider Sezary syndrome to be relatively distinct from typical MF. In Sezary syndrome, the cancerous T cell is a different type from that of MF.
While MF is the most common type of cutaneous T cell lymphoma, there are many other types, some of which are very rare.
Any additional symptoms may depend on the type of lymphoma that a person has.
Some people with MF experience no other symptoms, at first, beyond the rash.
The rash and plaques may get worse as the condition progresses. In some individuals, tumor-like lesions develop on the skin. The cancer may spread to the lymph nodes or other areas of the body.
Symptoms of spreading or progression can include:
- worsening itching
- lumps and bumps (lymphadenopathy)
- a fever
- night sweats
- weight loss
These symptoms can result from many types of lymphoma, including those that originate in areas other than the skin, known as systemic lymphomas.
The early symptoms can be easy to overlook, even for an experienced dermatologist, making the diagnosis challenging.
No standard diagnostic criteria for MF exist, and a diagnosis largely relies on the findings of a skin biopsy. To make matters more difficult, eczema and similar conditions can look like MF on a biopsy. For this reason, the doctor will usually take multiple biopsies.
Lymphoma can occur in anyone, though some people have a higher risk.
According to the American Cancer Society, lymphomas in the skin, such as MF, are more common in people in their 50s and 60s.
Also, males are almost twice as likely to develop MF as females.
Diagnosing a lymphoma rash, such as MF, can take time. The symptoms of lymphoma can be easy to miss at first, so seeing a doctor early on is vital.
Additionally, the patches and plaques on the skin can be similar to those of conditions such as eczema.
The diagnostic process will include physical examinations, questions about additional symptoms, and, often, blood tests.
The doctor will likely also check for signs of enlarged lymph nodes, and if these are present, they may request a biopsy of an enlarged node.
In addition, imaging tests can help doctors determine whether skin lymphoma has spread to other areas of the body. A doctor may use any of the following:
These imaging techniques help doctors check the organs and tissues for any abnormalities.
Treatment for lymphoma depends on the type and how far it has progressed.
Standard cancer therapies, such as the following, are common treatments for lymphoma:
For skin lymphomas, such as MF, doctors may recommend prescription topical creams or ointments that contain corticosteroids, chemotherapy drugs, or retinoids. These may help control pain and itchiness or clear the rash and help slow the progress of the cancer.
Most people with MF may also benefit from phototherapy, which uses ultraviolet light. Narrow-band ultraviolet B treatment is a very common phototherapy for MF.
In some cases, the doctor may prescribe a particular medication that aids treatment with ultraviolet A rays. The medical term for this combination is psoralen and ultraviolet A, or PUVA, therapy.
Combination therapies can be very effective in some cases. Authors of 2016 research found that 81% of people included in the study who had MF and a combination of drug and UV light therapy responded to treatment.
Surgery is not a common treatment for cutaneous T cell lymphoma unless a person has only an isolated plaque, which can occur with certain types of this lymphoma.
The outlook for a person with cutaneous T cell lymphoma depends on the type of the disease and how far it has advanced by the time that they receive a diagnosis.
Other factors also affect the outlook, such as the person's age, general health, and how well the cancer responds to treatment.
Many people with MF are able to manage symptoms and keep the cancer from progressing for long periods. In others, the disease progresses quickly and moves to other areas of the body.
Currently, there is no definitive cure for MF. Treatment aims to control the progression of the cancer and manage symptoms.