Anaplastic Large Cell Lymphoma Causes and Risk Factors

Anaplastic large cell lymphoma (ALCL) is a rare type of non-Hodgkin lymphoma, a cancer that starts in white blood cells called T-cells. Its exact causes are often unknown, but certain factors, including specific genetic changes, a weakened immune system, and textured breast implants, can increase your risk of developing it.

What is Anaplastic Large Cell Lymphoma Causes and Risk Factors?

Anaplastic large cell lymphoma (ALCL) is a rare cancer of the immune system, specifically affecting T-cells, a type of white blood cell. It is a subtype of non-Hodgkin lymphoma. While the precise reasons it develops are not fully understood, certain risk factors have been identified that can increase your likelihood of getting ALCL.

ALCL is characterized by the presence of large, abnormal T-cells. These cells grow and divide uncontrollably, forming tumors and interfering with the body's normal functions. It is considered a relatively aggressive lymphoma, meaning it can grow quickly. There are two main types of ALCL: systemic ALCL and breast implant-associated ALCL (BIA-ALCL). Systemic ALCL can affect lymph nodes and other organs throughout the body. BIA-ALCL is a very rare type of ALCL that develops in the fluid or scar tissue around breast implants. Understanding the potential causes and risk factors is important for both early detection and, in some cases, prevention. However, having a risk factor does not mean you will definitely get ALCL, and many people with ALCL have no known risk factors.

Symptoms

The symptoms of anaplastic large cell lymphoma (ALCL) can vary depending on where the cancer is located in your body. Common signs often include swollen lymph nodes, fever, night sweats, and unexplained weight loss, which are general symptoms seen in many types of lymphoma.

For systemic ALCL, the most common symptom is the painless enlargement of lymph nodes, often in the neck, armpit, or groin. These swollen lymph nodes (lymphadenopathy) may be noticeable as lumps under your skin. You might also experience general symptoms known as "B symptoms," which include fevers that come and go, drenching night sweats, and losing weight without trying. Other possible symptoms of systemic ALCL can include skin rashes or lumps, fatigue (extreme tiredness), and pain in bones or joints if the lymphoma has spread to those areas. The specific symptoms depend on which organs are affected by the cancer. For breast implant-associated ALCL (BIA-ALCL), symptoms typically appear around the breast implant. These can include new swelling or pain in the breast, a lump or mass near the implant, or a collection of fluid (seroma) around the implant. It's important to note that BIA-ALCL is not breast cancer, but a type of lymphoma.

Causes & risk factors

The exact causes of anaplastic large cell lymphoma (ALCL) are largely unknown, but scientists have identified several factors that can increase your risk. These include specific genetic changes within cells, a weakened immune system, and, in a rare form, the presence of textured breast implants.

One significant risk factor for systemic ALCL is a specific genetic change (mutation) in the cancer cells. About half of all systemic ALCL cases, especially in children and young adults, involve a rearrangement of the *ALK* gene (anaplastic lymphoma kinase). This genetic change causes cells to produce an abnormal protein that promotes uncontrolled cell growth. ALCL is then classified as either ALK-positive or ALK-negative, which affects treatment and outlook. Another risk factor is having a weakened immune system. People with conditions that suppress the immune system, such as HIV/AIDS, or those who take immunosuppressant medications after an organ transplant, have a higher risk of developing various lymphomas, including ALCL. A compromised immune system may be less effective at identifying and destroying abnormal cells before they become cancerous. For breast implant-associated ALCL (BIA-ALCL), the primary risk factor is having textured breast implants. While extremely rare, BIA-ALCL is more commonly associated with textured implants than with smooth ones. The exact mechanism is still being studied, but it's thought that chronic inflammation or an immune reaction to the implant surface may play a role in its development. It is crucial to remember that BIA-ALCL is not breast cancer and is considered very rare even among people with textured implants.

How it's diagnosed

Diagnosing anaplastic large cell lymphoma (ALCL) typically involves a biopsy, where a small sample of affected tissue, such as a swollen lymph node or fluid around a breast implant, is removed. This sample is then examined under a microscope to identify the specific cancer cells and confirm the diagnosis.

Your doctor will likely start with a physical exam, checking for swollen lymph nodes or other lumps. If ALCL is suspected, imaging tests like CT scans, PET scans, or MRI scans may be used to see where the lymphoma is in your body and if it has spread. Blood tests can also provide general information about your health and organ function. However, the definitive diagnosis of ALCL requires a biopsy. For systemic ALCL, this usually means a lymph node biopsy, where a whole lymph node or a piece of it is surgically removed. For BIA-ALCL, fluid around the breast implant (seroma fluid) or a piece of the capsule (scar tissue) surrounding the implant is typically collected. These samples are then sent to a pathologist. In the lab, the pathologist will examine the cells for specific features of ALCL. Special tests, such as immunohistochemistry and genetic testing, are performed on the biopsy sample. These tests help confirm the diagnosis, determine if the *ALK* gene rearrangement is present (ALK-positive or ALK-negative), and distinguish ALCL from other types of lymphoma or cancer. A bone marrow biopsy may also be done to check if the lymphoma has spread to the bone marrow.

Treatment options

Treatment for anaplastic large cell lymphoma (ALCL) usually involves chemotherapy, often combined with other therapies like targeted drugs or radiation. The specific treatment plan depends on the type of ALCL (systemic or BIA-ALCL), its stage, whether it's ALK-positive or ALK-negative, and your overall health.

For systemic ALCL, the primary treatment is typically chemotherapy. A common chemotherapy regimen is CHOP, which combines several different chemotherapy drugs. For ALK-positive ALCL, some targeted therapies that specifically block the ALK protein may be used. For ALK-negative ALCL, or if ALK-positive ALCL returns after initial treatment, other targeted drugs like brentuximab vedotin, which delivers a chemotherapy agent directly to lymphoma cells, may be used. Radiation therapy may be used in some cases, especially if the lymphoma is localized to a specific area. In situations where the lymphoma is aggressive, has returned, or is high-risk, a stem cell transplant (either using your own stem cells or those from a donor) might be considered after high-dose chemotherapy. For breast implant-associated ALCL (BIA-ALCL), the main treatment is often surgical removal of the breast implant and the entire surrounding capsule (the scar tissue that forms around the implant). In some cases, chemotherapy or radiation therapy may be recommended after surgery, especially if the disease has spread beyond the capsule. Your medical team will discuss the best approach based on your individual situation.

Recovery & outlook

The outlook for people with anaplastic large cell lymphoma (ALCL) varies significantly based on several factors, including the specific type of ALCL (ALK-positive or ALK-negative), how advanced it is at diagnosis, and how well it responds to treatment. Many people achieve remission, especially with ALK-positive ALCL.

For systemic ALCL, the presence of the *ALK* gene rearrangement (ALK-positive) generally indicates a better prognosis, particularly in children and young adults. Many people with ALK-positive ALCL respond well to treatment and have high rates of long-term remission or cure. ALK-negative systemic ALCL can be more aggressive and may require more intensive treatment, and its outlook can be more variable. For breast implant-associated ALCL (BIA-ALCL), the prognosis is often excellent, especially when the disease is caught early and treated with complete surgical removal of the implant and the surrounding capsule. Most cases of BIA-ALCL are confined to the fluid or capsule around the implant and are successfully treated with surgery alone. After treatment, regular follow-up appointments are crucial to monitor for any signs of recurrence or new symptoms. This typically involves physical exams, blood tests, and imaging scans. Your doctor will discuss your specific prognosis and what to expect during and after treatment, emphasizing that individual outcomes can differ.

When to see a doctor

You should see a doctor if you notice any persistent or unexplained symptoms that could indicate anaplastic large cell lymphoma (ALCL) or another serious condition. These include new or growing swollen lymph nodes, fevers, night sweats, unexplained weight loss, or any changes around a breast implant.

It's important to pay attention to your body and seek medical advice for any concerning symptoms. Specifically, contact your doctor if you experience: * **New or growing painless lumps:** Especially in your neck, armpit, or groin, which could be swollen lymph nodes. * **Persistent fevers:** Fevers that occur without a clear infection and don't go away. * **Drenching night sweats:** Sweats so heavy that they soak your clothes or bedding. * **Unexplained weight loss:** Losing a significant amount of weight (e.g., more than 10% of your body weight) without trying. * **Persistent fatigue:** Extreme tiredness that doesn't improve with rest. If you have breast implants, contact your doctor if you notice any new swelling, pain, a lump, or fluid collection around the implant. While these symptoms can be caused by many less serious conditions, it's essential to have them evaluated by a qualified clinician to rule out ALCL or other health issues. Early detection and diagnosis are key for effective treatment.

Frequently asked questions

Is anaplastic large cell lymphoma (ALCL) contagious?

No, anaplastic large cell lymphoma (ALCL) is not contagious. It is a type of cancer that arises from abnormal cell growth within your own body and cannot be spread from person to person through contact or any other means.

Can ALCL be prevented?

Generally, systemic ALCL cannot be prevented because its exact causes are largely unknown. However, for breast implant-associated ALCL (BIA-ALCL), choosing smooth breast implants over textured ones may reduce the risk, though BIA-ALCL is very rare regardless of implant type.

What is the difference between ALK-positive and ALK-negative ALCL?

The difference lies in a specific genetic change. ALK-positive ALCL means the cancer cells have a rearrangement of the *ALK* gene, which often leads to a better prognosis and response to certain targeted therapies. ALK-negative ALCL lacks this genetic change and can sometimes be more aggressive.

How rare is anaplastic large cell lymphoma (ALCL)?

Anaplastic large cell lymphoma (ALCL) is considered a very rare cancer. It accounts for a small percentage of all non-Hodgkin lymphomas, making it uncommon in the general population. Breast implant-associated ALCL (BIA-ALCL) is even rarer.

Are there different types of ALCL?

Yes, there are two main types: systemic ALCL, which can affect lymph nodes and other organs, and breast implant-associated ALCL (BIA-ALCL), which develops around breast implants. Systemic ALCL is further classified as ALK-positive or ALK-negative based on a genetic mutation.

Does ALCL only affect certain age groups?

No, ALCL can affect people of all ages, from children to older adults. However, ALK-positive systemic ALCL is more commonly seen in children and young adults, while ALK-negative systemic ALCL tends to occur more often in older adults.

Sources

• MedlinePlus — Anaplastic Large Cell Lymphoma Causes and Risk Factors
• Mayo Clinic — Anaplastic Large Cell Lymphoma Causes and Risk Factors
• Cochrane Library — Anaplastic Large Cell Lymphoma Causes and Risk Factors