Chronic lymphocytic leukemia (CLL) is a type of cancer that affects white blood cells in the bone marrow and blood. It is a relatively uncommon type of cancer — only about 1% of new cancers diagnosed each year are CLL — but it’s the most common type of leukemia in adults.

Treatment options for CLL can differ from person to person based on factors like age, overall health, CLL symptoms, and the presence of certain molecular risk factors.

For many diagnosed with CLL (stage 0), simple observation without active treatment is an option. If active treatment is necessary, a variety of different therapies may be used, including:

  • chemotherapy
  • targeted medications
  • radiation therapy
  • surgery
  • leukapheresis (removal of cells from the blood)
  • stem cell transplant

The variety of therapeutic options available for CLL may make treatment confusing, leading to certain misconceptions. In this article, we look at some common myths about CLL treatment, including the evidence available on the use of complementary therapies for people with this disease.

Fact: New and improved treatment options have made CLL a survivable condition with the potential for long periods of remission.

Although there still isn’t a cure for CLL, some people living with the condition may be able to achieve long periods of remission with treatment. This is known as “progression-free survival.”

One 2016 study found that almost 54% of people with CLL who had a particular genetic marker — a mutated IGHV gene — achieved remission for nearly 13 years when treated with chemoimmunotherapy involving fludarabine, cyclophosphamide, and rituximab (FCR).

These results are encouraging, but FCR is an intense treatment and is not ideal for everyone.

A 2022 study comparing FCR with a more tolerable CLL regimen — ibrutinib plus rituximab (IR) — showed that more people who received IR experienced disease progression than people who received FCR, regardless of IGHV mutation status. In this study, 78% of people who received IR were still in remission after 5 years, compared with 51% who received FCR.

As treatment options for CLL have improved, so has the disease’s survivability. Data suggest that more than 70% of people with CLL live for at least 10 years after receiving their diagnosis, and survival rates have continued to increase since then.

Fact: Active surveillance is the standard treatment option for people with early CLL without symptoms.

In some cases, people with CLL may not have any symptoms and the changes in their blood counts may be low. In these cases, oncologists may choose a wait-and-watch approach known as active surveillance to monitor how their CLL progresses.

For some, the effects of CLL may be minimal for many years. Treatment may not be needed until blood counts start to increase or symptoms occur. Waiting to start treatment helps people with CLL avoid the side effects of treatment when it isn’t necessary without compromising survival later.

Fact: A diet high in processed foods may increase the risk of getting CLL. But there isn’t evidence that a diet change, fasting, or calorie restriction can reverse the course of the disease or improve treatment. A nutritious diet does make it easier to manage CLL symptoms and treatment.

There may be some truth to this myth. A study of nearly 2,000 people in Spain found that participants who ate a diet high in high fat dairy products, processed meats, refined grains, and sweets were more likely to develop CLL than those who didn’t.

These results suggest that a diet high in processed foods may contribute to the risk of developing CLL, but it doesn’t tell us whether a diet change can affect treatment.

Still, the Leukemia and Lymphoma Society recommends a diet rich in proteins, fruits, and vegetables to help your body cope with the effects of CLL and treatment and promote a healthy immune system.

Calorie restriction is not recommended because it can lower your body’s energy levels. Fasting can also affect the way certain medications used to treat CLL work in the body.

Fact: Some vitamins and supplements may boost your immune system, but there can be unintended negative effects on cancer treatment.

Many people believe that vitamins and supplements can help the body fight off cancer. But the evidence is limited, and there are risks with some supplements to be aware of.

Research has found that curcumin may play a role in the immune system’s anti-tumor response. One study found that curcumin may increase the efficacy of certain types of CLL medications, but this was looked at in cancer cells, not people. It’s still not clear whether curcumin supplements can affect the course of CLL or treatment in people with the condition.

Vitamin D deficiency is common in people with CLL, and one study found that over one-quarter have severe vitamin D deficiency (less than 10 ng/mL). According to a 2011 study, people with CLL who are vitamin D deficient are more likely to need treatment sooner and may have shorter overall survival.

But it’s not clear if taking vitamin D supplements helps. A 2016 study found that in people with CLL who were given vitamin D supplements (up to 4,000 IU per day), over one-third still didn’t achieve recommended levels of vitamin D in their system. Too much vitamin D can also cause other concerns, such as a toxic buildup of calcium in the blood known as hypercalcemia.

Certain types of supplements, like vitamins C and E, can also decrease the effectiveness of cancer medications or increase the likelihood of side effects.

Talk with your oncologist if you think a supplement may be needed.

Fact: People with CLL can benefit from regular physical activity.

Fatigue is common with cancer and cancer treatment. Some people with CLL may feel that their treatment makes it too difficult for them to exercise.

But research has found that people with CLL are still capable of meaningful physical activity. In one study involving older adults with CLL, participants were able to complete an average of 5 sessions per week for 12 weeks of high intensity interval training, which was linked to improved immune function and muscle strength.

Participants in the study also reported meaningful improvements in several measures of well-being, including physical, social, emotional, and functional well-being, as well as lymphoma symptoms.

Fact: Prescription cannabinoids may provide relief from some chemotherapy side effects, but their anticancer effects are limited in CLL.

The relationship between cannabis and cancer is complex. There’s some evidence that cannabis use may increase the likelihood of developing certain types of cancer, such as testicular cancer, melanoma, and prostate cancer. It’s not yet clear whether cannabis use is linked to CLL.

Cannabinoids are a type of molecule found in cannabis (marijuana). Two types of cannabinoids, dronabinol and nabilone, are approved for the treatment of nausea and vomiting caused by chemotherapy in cancer treatment. Your oncologist will be able to help you decide whether these medications are right for you.

There’s also some evidence that cannabinoids may have anticancer effects, but research has found that these effects are limited in CLL cells.

CLL is a chronic and slow-progressing cancer. While a complete cure is rare, the variety of therapeutic options that have become available over the years has increased survivability.

At the same time, the large number of treatment options and complementary therapies have generated certain misconceptions and made treatment confusing. It’s important to separate myths from facts and learn the limitations of certain popular therapeutic options to ensure that you receive the most effective treatment possible.