Cutaneous B-Cell Lymphoma

Primary cutaneous B-cell lymphoma (PCBCL) is a rare type of non-Hodgkin lymphoma that starts in your skin. The cancer develops from white blood cells called lymphocytes, or B cells. It usually looks like a rash, bump or tumor on your skin. Your healthcare provider may call the abnormal skin “lesions.”

Understanding this cancer can feel challenging. This is because unlike most B-cell lymphomas, PCBCL doesn’t start in lymphatic system tissue, like your lymph nodes. Instead, it develops from B cells in your skin. As the cancer starts in B cells and not skin cells, it’s a lymphoma involving your skin — not a skin cancer.

The good news is that most cutaneous B-cell lymphomas respond well to treatment. This cancer isn’t usually life-threatening. Most people diagnosed live healthy lives with regular check-ups.

Types of PCBCL

The two most common forms of PCBCL grow slowly. Your healthcare provider may describe them as “indolent.” They are:

• Primary cutaneous follicle center lymphoma: Lesions usually appear on your head, neck or chest. It’s slightly more common in males. This is the most common type.
• Primary cutaneous marginal zone B-cell lymphoma: The lesions are usually on your arms or upper body. This type is twice as common in males. It’s also called a lymphoproliferative disorder.

A third type of PCBCL is rare. It tends to grow fast (aggressive) and is harder to treat:

• Primary cutaneous diffuse large B-cell lymphoma, leg type: Lesions usually appear on your lower legs. The cancer often spreads to places other than skin. It’s most common in females older than 65.

Symptoms of cutaneous B-cell lymphoma

PCBCL may involve one lesion or several. They may appear on just one part of your body or many areas. They may be close together or spread out. Cutaneous B-cell lymphoma may look like:

• Flat, thickened areas of skin (plaques)
• Large, firm bumps (nodules) or small, pimple-like bumps
• Slightly raised skin that’s solid and smooth (papules)
• Skin patches that are reddish, blue, purple or brown
• Fast-growing bumps on your legs that turn into ulcers

The rare, more serious form of PCBCL that usually affects your lower legs may cause “B” symptoms, like:

• Fever
• Night sweats
• Unexplained weight loss

Cutaneous B-cell lymphoma causes

Scientists don’t know the exact cause of PCBCL. But they do know that it starts in B cells that affect your skin.

The normal B cells develop an error (mutation) in their DNA. The mutation causes them to become cancer cells that multiply out of control. The cancer causes skin lesions.

Risk factors

The main risk factor for PCBCL is having a weak immune system over the long term. For example, people who have HIV and recipients of an organ transplant tend to have weakened immune systems. There’s also an association between hepatitis C infections and PCBCL.

How doctors diagnose this condition

Your healthcare provider can diagnose PCBCL with a physical exam and skin biopsy. During the exam, they’ll look for unusual skin lesions. During the biopsy, they’ll test tissue samples to look for PCBCL. The biopsy also shows what type you have.

Afterward, you’ll need tests to see if the cancer is only in your skin or if it’s spread. The treatment for lymphoma that’s only in your skin is different from lymphoma that’s in other places.

Tests include:

• Blood tests
• Imaging tests (CT scan or PET scan)
• Biopsies that check for cancer in your bone marrow and lymph nodes

Stages of B-cell skin lymphoma

The PCBCL stage describes whether the cancer has spread and how much. The cancer stage is important because it helps your provider plan treatment. Most PCBCL is stage 1E. This means it affects only your skin and hasn’t spread anywhere else. It may also be called stage 1AE if you don’t have “B” symptoms, like weight loss.

Your healthcare provider will explain how the cancer stage relates to your treatment.

How is cutaneous B-cell lymphoma treated?

Treatment for PCBCL depends on the type, how many lesions you have and how spread out they are. Usually, it involves destroying or removing the lesions. Options include:

• Active surveillance: With slow-growing PCBCL, you may not need medicine or a procedure right away. Instead, your provider may “watch and wait” until treatment is necessary.
• Radiation therapy: Usually, treatment involves getting radiation that destroys the lesions. Only the parts of skin with PCBCL get exposed to radiation.
• Surgery: You may have surgery if you only have a few lesions and they’re easy to remove. But radiation may be a better option if you’re worried about scarring.
• Corticosteroids: You may get this medicine rubbed on your skin. Or you may get it as an injection. This treatment is mostly for smaller lesions.
• Chemotherapy: Chemotherapy drugs treat the aggressive type of PCBCL. The chemo travels through your bloodstream to kill cancer throughout your body.
• Immunotherapy: Immunotherapy also treats aggressive PCBCL. You may also need this treatment if you have a slow-growing type of PCBCL but you’ve got lesions in many places. The most common treatment is rituximab.

When should I see my healthcare provider?

Contact your healthcare provider if you have any unusual chemotherapy or immunotherapy side effects. Your provider will explain possible side effects before you get treatment. Make sure you know which ones are to be expected and which ones require a doctor’s appointment.

Can cutaneous B-cell lymphoma be cured?

CBCL usually goes away with treatment. Half the time, it’s cured. It goes away and doesn’t come back. When it does come back, it usually goes away again with treatment. Most people with PCBCL live the rest of their lives with the condition. They don’t usually die from it.

It’s possible for PCBCL to progress to more serious forms of lymphoma. But this is incredibly rare. Still, your healthcare provider will monitor you closely to check for new growths.

What is the survival rate of cutaneous B-cell lymphoma?

The prognosis (likely outcome) for most CBCL is excellent. The more common types that grow slowly have a five-year survival rate of 95% to 100%. This means that most people diagnosed are alive five years later.

The rarer, more aggressive type has a five-year survival rate of 60% to 70%. This means 6 to 7 out of 10 people are alive five years later. Newer treatments, like immunotherapy, are helping people live longer than ever.

Is there anything I can do to feel better?

One of the best things you can do is understand how your diagnosis will affect your daily life. This includes knowing how often you’ll need check-ups to look for new lesions.

The frequency of appointments depends on factors unique to you. You may need a check-up every few weeks, months or annually. Follow-up appointments may involve skin checks, blood work, imaging tests or biopsies.