Cancer starts when cells begin to grow out of control. Cells in nearly any part of the body can become cancer, and can spread to other areas. To learn more about how cancers start and spread, see What Is Cancer?

Lymphoma is a cancer that starts in white blood cells called lymphocytes, which are part of the immune system. The main types of lymphomas are:

• Hodgkin lymphoma (also known as Hodgkin’s lymphoma, Hodgkin disease, or Hodgkin’s disease)
• Non-Hodgkin lymphoma (also known as non-Hodgkin’s lymphoma, NHL, or sometimes just lymphoma), which includes all skin lymphomas

Lymphocytes are in the lymph nodes (small, bean-sized collections of immune cells throughout the body) and other lymphoid tissues (such as the spleen, bone marrow, and some other organs, including the skin). Lymphomas can start in any of these places.

When a non-Hodgkin lymphoma starts only in the skin (not in other organs or tissues) it is called a skin lymphoma (or cutaneous lymphoma). A lymphoma that starts in lymph nodes or another part of the body and then spreads to the skin is not a skin lymphoma (because it didn’t start there).

Hodgkin lymphoma and other types of non-Hodgkin lymphoma are discussed on separate pages.

The lymph system and lymphoid tissue

To understand what lymphoma is, it helps to know something about the lymph system (also known as the lymphatic system). The lymph system is part of the immune system, which helps fight infections and some other diseases. The lymph system also helps fluids move around the body.

Lymphocytes

The lymph system is made up mainly of lymphocytes, a type of white blood cell. The main types of lymphocytes are:

• B lymphocytes (B cells): B cells normally help protect the body against germs (bacteria or viruses) by making proteins called antibodies. The antibodies attach to the germs, marking them for destruction by other parts of the immune system.
• T lymphocytes (T cells): There are several types of T cells, each with a special job. Some T cells destroy germs or abnormal cells in the body. Other T cells help boost or slow the activity of other immune system cells.

Both types of lymphocytes can develop into lymphoma cells. In the skin, T-cell lymphomas are more common than B-cell lymphomas.

Doctors can tell B cells and T cells apart with lab tests that detect certain proteins on their surfaces and certain features of their DNA. These tests also can recognize several stages of B-cell and T-cell development. This can help doctors figure out which type of lymphoma a person has, which can help determine their treatment options.

Lymph tissue

Most lymphocytes are in lymph nodes, which are bean-sized collections of lymphocytes and other immune system cells throughout the body. Lymph nodes are connected to each other by narrow tubes like blood vessels called lymphatics (or lymph vessels), which carry a colorless, watery fluid (lymph) that contains lymphocytes.

Along with the lymph nodes, lymphocytes can be found in the blood and in lymphoid tissues in many other places in the body, including the:

• Spleen
• Bone marrow (the soft, inner parts of certain bones)
• Thymus
• Adenoids and tonsils
• Digestive tract
• Skin
• Other organs

Lymphomas can start in any part of the body that contains lymph tissue.

Some other types of cancer, such as lung cancer or colon cancer, can spread to lymph tissue such as the lymph nodes. But cancers that start in these places and then spread to the lymph tissue are not lymphomas.

Research into the causes, prevention, and treatment of lymphoma of the skin is being done in many medical centers throughout the world.

Genetics

As noted in What Causes Lymphoma of the Skin? scientists are making progress in learning how changes in the DNA inside normal lymphocytes can cause them to develop into lymphoma cells. Understanding these changes can provide insight into why these cells grow too quickly, live too long, and don’t develop into normal mature cells. It might also lead to new drugs that specifically target these processes.

Our understanding of these DNA changes has already led to the development of highly sensitive lab tests for detecting this disease. For example, polymerase chain reaction (PCR) is a very sensitive test that can help tell if a lymphoma has been destroyed by treatment or if a relapse is likely. These types of tests could help doctors pick out those patients who need more intensive treatment.

Skin-directed treatments

Several newer types of skin-directed treatments are now being studied for the treatment of early stage skin lymphomas.

Photodynamic therapy (PDT)

For this treatment, a light-activated drug called aminolevulinic acid (ALA) is applied to the skin lesions. A special type of laser light is then focused on the lesions. This light changes the drug that has collected inside the lymphoma cells, which kills them.

The advantage of PDT is that it can kill cancer cells with very little harm to normal cells. But because the chemical must be activated by light, it can only kill cancer cells near the surface of the skin. This limits its use to early-stage skin lymphomas that have not grown deeply into the skin. Even then, PDT might only be used if other types of skin-directed therapies are not effective. You can find out more about PDT in Photodynamic Therapy.

Topical imiquimod and resiquimod

These drugs affect a protein called TLR7. When applied to a skin lesion as a cream or gel, they can cause a local immune reaction, which can kill skin lymphoma cells. More research is needed to help determine their safety and effectiveness, although imiquimod is already available to treat some other skin conditions, so doctors can use it off-label to treat skin lymphomas.

Chemotherapy

Many clinical trials are studying newer chemotherapy drugs. One that has shown some promise in early clinical trials is forodesine. Research on this and other new drugs continues.

Other studies are looking at ways of combining drugs already known to be effective in new ways or using different doses or different sequences of these drugs.

Targeted drugs

Newer drugs known as targeted therapies have shown clear benefit in certain kinds of skin lymphoma. The drugs vorinostat (Zolinza) and romidepsin (Istodax) are forms of targeted therapy that can help treat some skin lymphomas. Doctors are now studying how to use these drugs most effectively.

Other targeted drugs are also being studied for skin lymphomas, including everolimus (Afinitor), lenalidomide (Revlimid), and bortezomib (Velcade).

Monoclonal antibodies

Lymphoma cells have certain proteins on their surface. Special man-made antibodies that recognize these proteins can be targeted to destroy the lymphoma cells while causing little damage to normal body tissues.

Several such drugs, including rituximab (Rituxan) and brentuximab vedotin (Adcetris), are already used to treat some skin lymphomas. These are discussed in Whole Body (Systemic) Treatments for Skin Lymphomas.

New monoclonal antibodies are also being developed. One example is mogamulizumab, an antibody that targets the CCR4 protein. This drug has shown promise for treating skin lymphoma in a recent late-stage clinical trial.

Immune checkpoint inhibitors

A promising newer area of cancer treatment is immunotherapy, which helps a person’s own immune system attack cancer cells in the body. Immunotherapy drugs called checkpoint inhibitors are monoclonal antibodies that help boost the immune response. These drugs have been found to be helpful in treating many types of cancer, and some of them are now being studied for use against skin lymphomas. Examples include pembrolizumab (Keytruda), durvalumab (Imfinzi), and atezolizumab (Tecentriq). Some studies are testing these drugs along with other treatments such as radiation therapy, which might help them work better.

Stem cell transplant

High-dose chemotherapy followed by a stem cell transplant is sometimes used to treat lymphomas that no longer respond to other treatments. Researchers continue to improve stem cell transplant methods, including new ways to harvest these cells before transplantation.

A lot of research is focusing on reducing graft-versus-host disease in allogeneic transplants (using stem cells from a donor). This work involves altering the transplanted T-cells so that they won’t react with the patient’s normal cells but will still kill the lymphoma cells.

Because this type of lymphoma affects the skin, it is often noticed fairly quickly. But the actual diagnosis of skin lymphoma might be delayed because the symptoms often resemble other, more common skin problems. The diagnosis of skin lymphoma can only be confirmed with a skin biopsy (described below). Other tests might be needed as well.

Medical history and physical exam

When a doctor takes your medical history, you will be asked about your symptoms, possible risk factors, family history, and other medical conditions. The doctor will ask when you first noticed the changes in your skin, if they have changed in size or appearance, and if they are itchy or painful. You may be asked if you have any other symptoms, like fever or weight loss. Because skin lymphomas can be hard to tell apart from allergies and other causes of rashes, you might also be asked if you have any allergies or have recently been exposed to something that could be causing your skin problems, such as a new medicine or a new laundry detergent or any new creams or lotions.

During the physical exam, your doctor will note the size, shape, color, and texture of any area(s) of skin in question. The rest of your body will be checked for other areas of skin involvement.

The doctor might also feel the lymph nodes (small, bean-sized collections of immune cells) under the skin in your neck, underarms, or groin, as lymphomas can sometimes cause lymph nodes to become enlarged.

If you are being seen by your primary doctor, you may be referred to a dermatologist (a doctor who treats skin diseases), who will look at your skin more closely.

Skin biopsies

A biopsy is a procedure in which a doctor removes a sample of body tissue for viewing under a microscope or other lab tests. A biopsy is needed to diagnose lymphoma of the skin.

There are several types of skin biopsies, and the doctor’s choice of which one to use is based on each person’s situation. Usually a skin biopsy is done by a dermatologist.

Punch biopsy

For a punch biopsy, the doctor uses a tool that looks like a tiny round cookie cutter (usually a little more than 1/8 inch across). Once the skin is numbed with a local anesthetic, the doctor rotates the punch biopsy tool on the surface of the skin until it cuts through all the layers of the skin.The piece of skin is then removed. Often the biopsy site is closed with a stitch.

Incisional and excisional skin biopsies

For these types of biopsies, a surgical knife is used to cut through the full thickness of skin. An incisional biopsy removes only part of the tumor, while an excisional biopsy removes the entire tumor. The piece of skin is removed for testing, and the edges of the cut are sewn together. These biopsies are usually done using a local anesthetic (numbing medicine).

Regardless of the type of skin biopsy, once the samples are removed, they are sent to a doctor called a pathologist, who will look at them under a microscope and might do other tests on them (see below).

Many of the more common forms of skin cancer (and other skin diseases) can be diagnosed just by looking at the biopsy samples under a microscope. But diagnosing and classifying lymphomas of the skin often requires one or more special lab tests (see below).

Diagnosing some forms of skin lymphoma can be very challenging. Sometimes, especially if the diagnosis is unclear, the skin samples may need to be sent to a dermatopathologist, a dermatologist or a pathologist with additional training in diagnosing skin samples. Even with this expertise, in some cases several biopsies may be needed over a period of time before the diagnosis is confirmed.

Lymph node biopsies

Skin lymphomas often spread to lymph nodes, so your doctor may recommend a lymph node biopsy to help confirm the diagnosis or to help determine how widespread the lymphoma is. This is more likely to be done if the doctor detects enlarged lymph nodes, either during a physical exam or with imaging tests (see below).

Excisional or incisional lymph node biopsies

These are the most common types of lymph node biopsy. In these procedures, a surgeon cuts through the skin to remove either the entire lymph node (excisional biopsy) or a small part of a large tumor (incisional biopsy). If the node is just under the skin, this is often a simple operation that can be done with local anesthesia. But if the node is inside the chest or abdomen, the patient will need to be asleep or deeply sedated during the biopsy.

Removing a lymph node almost always provides enough tissue to diagnose the exact type of lymphoma. Most doctors prefer this type of biopsy, if it can be done without too much discomfort to the patient.

Needle biopsy

 In a needle biopsy, the doctor uses a thin, hollow needle to remove a small amount of tissue from a tumor. This can be done as a fine needle aspiration (FNA), which uses a very thin needle, or a core needle biopsy, which uses a slightly larger needle.

If an enlarged node is just under the skin, the doctor can aim the needle while feeling the node. If the enlarged node is deep inside the body, the doctor can guide the needle while viewing it with an imaging test such as an ultrasound or a CT scan (see below).

A needle biopsy does not require surgery, but in some cases this type of biopsy (especially an FNA) might not remove enough tissue to make a definite diagnosis of lymphoma. But advances in lab tests (discussed later in this section) and the growing experience of many doctors have improved the accuracy of this procedure.

Other types of biopsies

These procedures may sometimes be done to confirm a diagnosis of lymphoma, but they are more often done to help determine the stage (extent) of a lymphoma that has already been diagnosed. Not everyone with lymphoma of the skin needs these tests.

Bone marrow aspiration and biopsy

These tests are sometimes done after lymphoma has been diagnosed to help figure out if it has spread to the bone marrow (the soft, inner part of certain bones). The two tests are often done at the same time. The samples are usually taken from the back of the pelvic (hip) bone, but in some cases they may be taken from other bones.

In bone marrow aspiration, you lie on a table (either on your side or on your belly). The doctor cleans the skin over the hip and then numbs the area and the surface of the bone by injecting a local anesthetic. This may cause a brief stinging or burning sensation. A thin, hollow needle is then inserted into the bone and a syringe is used to suck out a small amount of liquid bone marrow. Even with the anesthetic, most patients still have some brief pain when the marrow is removed.

A bone marrow biopsy is usually done just after the aspiration. A small piece of bone and marrow is removed with a slightly larger needle that is pushed down into the bone. This may also cause some brief pain. Once the biopsy is done, pressure will be applied to the site to help stop any bleeding.

Lumbar puncture (spinal tap)

This test looks for lymphoma cells in the cerebrospinal fluid (CSF), which is the liquid that bathes the brain and spinal cord. Most people with skin lymphoma will not need this test. But doctors may order it if a person has symptoms that suggest the lymphoma might have reached the brain.

For this test, you may be asked to lie on your side or sit up. The doctor first numbs an area in the lower part of the back over the spine. A small, hollow needle is then inserted between the bones of the spine to withdraw some of the fluid.

Lab tests of biopsy or blood samples

Lab tests are done on the biopsy samples (and in some cases, blood samples) to help diagnose lymphoma and determine what type it is. Pathologists can sometimes tell which kind of lymphoma a patient has by just looking at the cells under a microscope, but usually these other types of tests are needed to confirm the diagnosis.

Flow cytometry and immunohistochemistry

For both flow cytometry and immunohistochemistry, samples of cells are treated with special antibodies that stick to certain proteins on cells. For immunohistochemistry, the cells are then looked at under a microscope to see if the antibodies stuck to them (meaning they have these proteins), while for flow cytometry a special machine is used.

These tests can help determine whether a lymph node is swollen because of lymphoma, some other cancer, or a non-cancerous disease. The tests can also be used for immunophenotyping – determining which type of lymphoma a person has, based on certain proteins in or on the cells. Different types of lymphocytes have different proteins on their surface.

Chromosome tests

Normal human cells have 23 pairs of chromosomes (strands of DNA), each of which is a certain size and looks a certain way under the microscope. But in some types of lymphoma, the cells have changes in their chromosomes, such as having too many, too few, or abnormal chromosomes. These changes can often help identify the type of lymphoma.

Cytogenetics: In this lab test, the cells are looked at under a microscope to see if the chromosomes have any abnormalities. A drawback of this test is that getting the results usually takes about 2 to 3 weeks because the cells must grow in lab dishes for a couple of weeks.

Fluorescent in situ hybridization (FISH): This test looks more closely at lymphoma cell DNA using special fluorescent dyes that only attach to specific genes or parts of chromosomes. FISH can find most chromosome changes that can be seen in standard cytogenetic tests, as well as some gene changes too small to be seen with cytogenetic testing. FISH is very accurate and can usually provide results within a couple of days.

Polymerase chain reaction (PCR): PCR is a very sensitive DNA test that can find gene changes and certain chromosome changes too small to be seen with a microscope, even if very few lymphoma cells are present in a sample.

Blood tests

Blood tests measure the amounts of certain types of cells and chemicals in the blood. They are not used to diagnose lymphoma, but they can sometimes help determine how advanced the lymphoma is. They may also be used during certain types of treatment (such as chemotherapy) to monitor how well the bone marrow and other organs are functioning.

• Complete blood count (CBC): This test measures the levels of different cells in the blood, such as the red blood cells, the white blood cells, and the platelets. The CBC is often done with a differential (or “diff”) which counts the numbers of different types of white blood cells. If a person’s blood counts are low, it might mean that the lymphoma is growing in the bone marrow and slowing normal blood cell production. People with Sezary syndrome will have Sezary cells in the blood, which can be found on the differential.
• Blood chemistry tests: These tests look at how well organs such as the kidneys and liver are working.
• If lymphoma has been diagnosed, another blood test called lactate dehydrogenase (LDH) may be done. LDH levels are often abnormally high in patients with widespread lymphoma.
• For some types of lymphoma or if certain treatments might be used, your doctor may also advise you to have tests to see if you’ve been infected with certain viruses, such as hepatitis B virus (HBV), human T-cell lymphotropic virus (HTLV-1), or human immunodeficiency virus (HIV). Infections with these viruses might affect your treatment.

Imaging tests

Imaging tests use x-rays, sound waves, magnetic fields, or radioactive particles to make pictures of the inside of the body. In someone with known or suspected lymphoma, these tests might be done for a number of reasons, including:

• To help find suspicious areas that might be cancer
• To learn how far the lymphoma has spread
• To find out if treatment is working
• To look for possible signs of the lymphoma coming back after treatment

Imaging tests aren’t always needed for people with skin lymphomas who have only a few skin lesions, but they are often done if a lot of the skin is affected, or if lymphoma cells are found in the lymph nodes or blood.

If you’d like to learn more about any of the imaging tests discussed here, see Imaging (Radiology) Tests.

Chest x-ray

An x-ray of the chest may be done to look for enlarged lymph nodes in this area.

Computed tomography (CT) scan

The CT scan uses x-rays to make detailed, cross-sectional images of your body. Unlike a regular x-ray, CT scans can show the detail in soft tissues (such as internal organs). This scan can help tell if any lymph nodes or organs in your body are enlarged.

CT-guided needle biopsy: A CT scan can also be used to guide a biopsy needle into a suspicious area. For this procedure, you lie on the CT scanning table while the doctor advances a biopsy needle through the skin and toward the area. CT scans are repeated until the needle is in the right place. A biopsy sample is then removed and sent to the lab to be looked at under a microscope.

Magnetic resonance imaging (MRI) scan

Like CT scans, MRI scans show detailed images of soft tissues in the body. But MRI scans use radio waves and strong magnets instead of x-rays. MRI scans are very helpful in looking at the brain and spinal cord, but they are not often used to evaluate skin lymphomas unless a CT scan can’t be done for some reason.

Ultrasound

Ultrasound can be used to look at lymph nodes near the surface of the body or to look inside your abdomen for enlarged lymph nodes or organs such as the liver and spleen. (It can’t be used to look at organs or lymph nodes in the chest because the ribs block the sound waves.) It is sometimes used to help guide a biopsy needle into an enlarged lymph node.

This is an easy test to have, and it uses no radiation. You simply lie on a table, and a technician moves the transducer over the part of your body being looked at.

Positron emission tomography (PET) scan

For a PET scan, you are injected with a slightly radioactive form of sugar, which collects mainly in cancer cells. A special camera is then used to create a picture of areas of radioactivity in the body. The picture is not detailed like a CT or MRI scan, but it can look for possible areas of lymphoma in all areas of the body at once.

A PET scan can help tell if an enlarged lymph node contains lymphoma or is benign. It can also help spot small areas that might be lymphoma, even if the area looks normal on a CT scan.

PET scans can also be used to tell if an advanced skin lymphoma is responding to treatment. Some doctors will repeat the PET scan after a few courses of chemotherapy. If the chemo is working, the abnormal areas will no longer take up the radioactive sugar.

Doctors often use a machine that does both a PET and CT scan at the same time (PET/CT scan). This lets the doctor compare areas of higher radioactivity on the PET scan with the more detailed appearance of that area on the CT scan.

Lymphomas of the skin can be seen and felt. They can appear as:

• Papules (small, pimple-like lesions)
• Patches (flat lesions)
• Plaques (thick, raised or lowered lesions)
• Nodules or tumors (larger lumps or bumps under the skin)

The lesions are often itchy, scaly, and red to purple. The lymphoma might show up as more than one type of lesion and on different parts of the skin (often in areas not exposed to the sun). Some skin lymphomas appear as a rash over some or most of the body (known as erythroderma). Sometimes larger lesions can break open (ulcerate).

Along with skin problems, in rare cases lymphoma of the skin can cause general symptoms, such as:

• Unexplained weight loss
• Fever
• Profuse sweating (enough to soak clothing), particularly at night
• Severe itchiness

Sometimes a skin lymphoma can reach the lymph nodes (small, bean-sized collections of immune cells), which can make them bigger. An enlarged lymph node might be felt as a lump under the skin in the neck, underarm, or groin area.

Most of these symptoms are more likely to be caused by other, less serious conditions. Still, if you have any of them it's important to have them checked by a doctor so that the cause can be found and treated, if needed.

It’s important to have honest, open discussions with your cancer care team. They want to answer all of your questions, no matter how minor they might seem. For instance, consider asking these questions:

When you're told you have lymphoma of the skin

• What kind of skin lymphoma do I have?
• Has my biopsy been reviewed by a pathologist who is an expert on skin lymphoma?
• How sure are you of my diagnosis?
• What is the stage (extent) of the lymphoma, and what does that mean in my case?
• Do I need any other tests before we can decide on treatment?
• Do I need to see any other types of doctors?
• If I’m concerned about the costs and insurance coverage for my diagnosis and treatment, who can help me?

When deciding on a treatment plan

• How much experience do you have treating this type of lymphoma?
• Should I get a second opinion before starting treatment? Can you suggest a doctor or cancer center?
• What are my treatment choices?
• What do you recommend and why?
• Do we need to treat the lymphoma right away?
• What is the goal of the treatment?
• What should I do to be ready for treatment?
• How long will treatment last? What will it be like? Where will it be done?
• What are the risks or side effects of the treatments you suggest?
• How will treatment affect my daily activities?
• What is my outlook for survival?
• What are the chances of the lymphoma coming back with these treatment plans?
• What would we do if the treatment doesn’t work or if the lymphoma recurs?

During treatment

Once treatment begins, you’ll need to know what to expect and what to look for. Not all of these questions may apply to you, but getting answers to the ones that do may be helpful.

• How will we know if the treatment is working?
• Is there anything I can do to help manage side effects?
• What symptoms or side effects should I tell you about right away?
• How can I reach your office on nights, holidays, or weekends?
• Are there any limits on what I can do? 
• Can you suggest a mental health professional I can see if I start to feel overwhelmed, depressed, or distressed?

After treatment

• What type of follow-up will I need after treatment?
• What symptoms should I watch for?
• How will we know if the lymphoma has come back? What would my options be if that happens?

Along with these sample questions, be sure to write down some of your own. For instance, you might want more information about recovery times so that you can plan your work or activity schedule. Or you might ask about clinical trials.

Keep in mind that doctors aren't the only ones who can give you information. Other health care professionals, such as nurses and social workers, might be able to answer some of your questions. See The Doctor-Patient Relationship.

The American Cancer Society’s most recent estimates for all types of non-Hodgkin lymphoma (NHL) in the United States for 2018 are:

• 74,680 new cases of NHL (41,730 in men and 32,950 in women)
• 19,910 deaths from NHL (11,510 in men and 8,400 in women)

However, lymphomas of the skin are uncommon, accounting for only about 4% of all non-Hodgkin lymphomas. The rate of skin lymphomas has been rising over the past few decades, although it seems to have leveled off in recent years. The reasons for this are not known.

Survival rates for skin lymphomas can vary a great deal, depending on the type of lymphoma, how advanced it is, and how well it responds to treatment.

A risk factor is anything that increases your chance of getting a disease like cancer. Different cancers have different risk factors. Some risk factors, like smoking, can be changed. Others, like a person’s age or family history, can’t be changed.

But having a risk factor, or even several, does not mean that a person will get the disease. And many people who get the disease may have few or no known risk factors.

While most people with lymphoma of the skin may have some factors (such as their age or gender) that make them more likely to get this disease, in most people there is no clear cause of the lymphoma.

Age

Age is an important risk factor for this disease, with most skin lymphomas occurring in people in their 50s and 60s. But some types of skin lymphoma can appear in younger people, even in children.

Gender and race

Most (but not all) types of skin lymphoma are more common in men than in women. Most also tend to be more common in African-Americans than in whites. The reasons for this are not known.

Having a weakened immune system

Skin lymphomas may be more common in people who have a weakened immune system. This includes people with acquired immunodeficiency syndrome (AIDS), as well as people who have had an organ transplant such as a heart, kidney or liver transplant, who must take drugs that suppress their immune system.

Certain infections

Infection with certain viruses or other germs has been suggested as a possible cause of some skin lymphomas.

Infection with the HTLV-1 virus has been linked with the rare adult T-cell leukemia/lymphoma, although most people infected with this virus do not develop lymphoma. This infection is most often seen in parts of Japan and the Caribbean.

Infection with Epstein-Barr virus (EBV) has been linked with some types of lymphoma, including extranodal NK/T-cell lymphoma, nasal type. But EBV infection is common, and most people infected with EBV do not go on to develop lymphoma.

In parts of Europe (but not in the United States), infection with Borrelia, the bacteria that causes Lyme disease, has also been linked with some skin lymphomas. This link has only been reported in a small number of cases—most people with skin lymphoma have not had Lyme disease, and most people with Lyme disease do not develop lymphoma of the skin.

Infection with the human immunodeficiency virus (HIV), the virus that causes AIDS, may increase a person’s risk of skin lymphoma by weakening their immune system.

Some studies have suggested that infections with other viruses might also be linked with skin lymphomas, but more research is needed on this.

Some risk factors can make a person more likely to get lymphoma of the skin, but it’s not always clear exactly how these factors might increase risk.

Scientists have learned how certain changes in the DNA inside normal lymphocytes (immune system cells) might cause them to become lymphoma cells. DNA is the chemical in each of our cells that makes up our genes, which control how our cells function. We usually look like our parents because they are the source of our DNA. But DNA affects more than just how we look.

Some genes control when our cells grow, divide into new cells, and die at the right time:

• Certain genes that help cells grow, divide, or live longer are called oncogenes.
• Genes that help keep cell division under control or cause cells to die at the right time are called tumor suppressor genes.

Cancers can be caused by DNA changes that turn on oncogenes or turn off tumor suppressor genes.

Some people inherit DNA mutations (changes) from a parent that increase their risk of developing some types of cancer. But lymphoma of the skin is not one of the cancer types often caused by inherited mutations.

DNA changes related to lymphoma of the skin are usually acquired after birth, rather than being inherited. Some of these acquired changes may have outside causes (such as infections), but often they occur for no apparent reason. They seem to happen more often as we age, which may help explain why most types of skin lymphomas usually occur in older people.

Scientists are learning about the exact gene changes that cause skin lymphomas. But even though they have found some of these gene changes, they still do not know why these changes occur.

The immune system seems to play an important role in some skin lymphomas. People with weakened immune systems (such as people with acquired immunodeficiency syndrome (AIDS) and people who have had an organ transplant) seem to have a greater chance of developing skin lymphoma, but it’s not clear why.

Some types of infections might also raise the risk of skin lymphomas. This might be because the infections force the body’s immune system to constantly be active. As more lymphocytes are made to fight the infection, there is a greater chance that some of these cells will have DNA mutations in key genes, which might eventually lead to lymphoma. Researchers are still studying this. 

Most lymphomas of the skin have no known cause, so there is no sure way to prevent them from developing.

Having a weakened immune system may raise your risk of skin lymphoma, so making sure your immune system stays healthy might be one way to limit your risk. An example of this would be to avoid known risk factors for infection with HIV (the virus that causes AIDS), such as intravenous drug use or unprotected sex with someone whose HIV status is unknown. You can read more about HIV infection in HIV, AIDS, and Cancer.

This type of lymphoma first appears in the skin, so it is usually found earlier in the course of the disease than many other types of cancer. Unfortunately, it is sometimes hard even for experienced doctors to diagnose skin lymphomas right away because they often look like other, more common skin problems such as infections or eczema.

The best approach is to see a doctor if you notice symptoms that might be from a skin lymphoma (or another type of skin cancer). This includes any new lesion (abnormal area) on the skin, especially if it is raised, if it breaks open or bleeds, if it doesn’t go away, or if it is growing.

For some people with skin lymphoma, treatment can remove or destroy the cancer. Completing treatment can be both stressful and exciting. You may be relieved to finish treatment, but find it hard not to worry about the lymphoma coming back. (When cancer comes back after treatment, it is called a recurrence.) This is a very common concern if you've had cancer.

For many people, the lymphoma may never go away completely. These people may get regular treatments such as chemotherapy, radiation, or other therapies to help keep the lymphoma under control for as long as possible and to help relieve symptoms from it. Learning to live with lymphoma that doesn't go awayt can be difficult and very stressful. It has its own type of uncertainty. See Managing Cancer as a Chronic Illness for more about this.

Follow-up care

Whether you have completed treatment or are still being treated, your doctors will still want to watch you closely with regular physical exams, blood tests, and possibly imaging tests. It's very important to go to all of your follow-up appointments. Your doctor visits are a good time to ask questions and talk about any changes or problems you notice or concerns you have.

Exams and tests

During your follow-up visits, your doctor will ask about symptoms, examine you, and may order some tests. For example, you may need to have frequent blood tests to monitor your bone marrow function, to check that you have recovered from treatment, and to look for possible signs of disease recurrence.

The choice of other tests depends on the type, location, and extent of your lymphoma. If lymph nodes or other organs are affected, CT scans may be used to measure the size of any remaining tumors. PET scans may be done if your doctors aren’t sure if an abnormal area on a CT scan is an active lymphoma or scar tissue.

Ask your doctor for a survivorship care plan

Talk with your doctor about developing a survivorship care plan for you. This plan might include: 

• A suggested schedule for follow-up exams and tests
• A schedule for other tests you might need in the future, such as early detection (screening) tests for other types of cancer, or tests to look for long-term health effects from your cancer or its treatment
• A list of possible late- or long-term side effects from your treatment, including what to watch for and when you should contact your doctor
• Diet and physical activity suggestions

Keeping health insurance and copies of your medical records

Even after treatment, it’s very important to keep health insurance. Tests and doctor visits cost a lot, and even though no one wants to think of their lymphoma coming back, this could happen.

At some point after your treatment, you might find yourself seeing a new doctor who doesn’t know about your medical history. It’s important to keep copies of your medical records to give your new doctor the details of your diagnosis and treatment. Learn more in Keeping Copies of Important Medical Records.

Can I lower my risk of the lymphoma progressing or coming back?

If you have (or have had) a skin lymphoma, you probably want to know if there are things you can do that might lower your risk of it growing or coming back, such as exercising, eating a certain type of diet, or taking nutritional supplements. Unfortunately, it’s not yet clear if there are things you can do that will help.

Adopting healthy behaviors such as not smoking, eating well, getting regular physical activity, and staying at a healthy weight might help, but no one knows for sure. However, we do know that these types of changes can have positive effects on your health that can extend beyond your risk of lymphoma or other cancers.

About dietary supplements

So far, no dietary supplements (including vitamins, minerals, and herbal products) have been shown to clearly help lower the risk of skin lymphoma progressing or coming back. This doesn’t mean that no supplements will help, but it’s important to know that none have been proven to do so.

Dietary supplements are not regulated like medicines in the United States – they do not have to be proven effective (or even safe) before being sold, although there are limits on what they’re allowed to claim they can do. If you’re thinking about taking any type of nutritional supplement, talk to your health care team. They can help you decide which ones you can use safely while avoiding those that might be harmful.

If the lymphoma comes back

If the lymphoma does come back at some point, further treatment will depend on the type of lmphoma, where it recurs, what treatments you’ve had before, and your health and preferences. For more information, see Treatment for Specific Types of Skin Lymphoma. For more general information on dealing with a recurrence, see Coping with Cancer Recurrence.

Can I still get another type of cancer?

Unfortunately, being treated for skin lymphoma doesn’t mean you can’t get another cancer. People who have had lymphoma of the skin can still get the same types of cancers that other people get. In fact, they might even be at higher risk for certain types of cancer, such as other lymphomas.

Because of this, it’s important to do what you can to lower your cancer risk, such as not smoking, staying at a healthy weight, staying active, and eating a healthy diet. And be sure to talk to your doctor about which cancer screening tests are right for you.

Getting emotional support

Some amount of feeling depressed, anxious, or worried is normal when cancer is a part of your life. Some people are affected more than others. But everyone can benefit from help and support from other people, whether friends and family, religious groups, support groups, professional counselors, or others. To learn more about this, see Coping With Cancer.