Blood cancer is a type of cancer that’s caused by abnormal blood cells that reproduce quickly. Those cells affect how normal blood cells function. Blood cancers usually start in the bone marrow, which is the part of the bone where the body makes new blood cells.
There are three main types of blood cancers:
— Leukemia: caused by the production of too many abnormal white blood cells. White blood cells help our body fight infection and are part of the immune system. The immune system helps to prevent infections and diseases. Those abnormal white blood cells can no longer fight infection. These malignant white blood cells also prevent the bone marrow from producing two other important types of blood cells: red blood cells and platelets.
— Lymphoma: a type of cancer related to your body’s lymphatic system. This network of organs and tissues produces cells that help the immune system; it also helps rid the body of cellular waste and maintain body fluid levels. Lymphoma causes the body to produce abnormal lymphocytes, a white blood cell that normally helps ward off infection. Those abnormal cells can gather in your lymph nodes and weaken your immune system.
— Myeloma: Plasma cells are a type of white blood cell that help your body produce antibodies that fight off disease and infection. Myeloma halts the normal production of those antibodies, which can weaken your immune system.
Each type of blood cancer has subtypes. Some of the most commonly diagnosed blood cancers include non-Hodgkin lymphoma, chronic lymphocytic leukemia and multiple myeloma.
Scientists aren’t sure what causes blood cancer. They believe it may be a mix of environmental and genetic factors. There are no broadly defined genetic causes, such as is the case with the BRCA gene associated with breast cancer in some patients, says Dr. Catherine Diefenbach, a hematologist/oncologist and director of hematology translational research and the Clinical Lymphoma Program at NYU Langone’s Perlmutter Cancer Center in New York City.
Some types of cancer, however, are associated with certain forms of blood cancer. For instance, people with breast cancer may develop acute myeloid leukemia in the future, says Dr. Guenther Koehne, deputy director and chief of stem cell transplantation, hematologic oncology and benign hematology at Miami Cancer Institute, part of Baptist Health South Florida in Miami.
Treatments for Blood Cancers
The treatment for blood cancer varies depending on the type of cancer a person has. Generally speaking, the treatments used for blood cancer include:
— Chemotherapy, or the use of drugs that cause cancer cells to die.
— Immunotherapy, or using the person’s immune system to fight cancer. The body’s immune cells are supposed to recognize and kill cancer cells, but that doesn’t always happen. Immunotherapy helps restore the ability of the immune cells to track and destroy cancer cells, says Dr. Felipe Samaniego, an associate professor in the department of lymphoma/myeloma at the Division of Cancer Medicine at MD Anderson Cancer Center in Houston. Immunotherapy is also called biologic therapy because it involves the use of biological material like cells, proteins and even viruses to treat cancer.
— Radiation, or the use of high-energy waves, usually X-rays, to kill cancer cells. Other energy waves used include gamma rays, electron beams and protons.
— Targeted therapy, which are drugs designed to specifically target cancer cells without harming healthy cells. This is more precise than chemotherapy, which usually kills cancer cells and some healthy cells. Targeted therapy can turn off the process that causes cancer cells to grow, cause cancer cells to die on their own or directly kill cancerous cells.
— Watching and waiting. Some blood cancers, such as certain types of lymphomas, may not need any immediate treatment because they are not fast moving, Koehne says. Doctors will watch these cancers over time to decide whether you need treatment.
Immunotherapy and Blood Cancer
Immunotherapy is an approach that’s become more popular for cancer treatment. That’s because it has helped treat cancers that have not been responsive to established treatments such as chemotherapy or radiation. Immunotherapy has been successful in aiding the treatment of a variety of cancer types, including kidney and lung cancer, as well as melanoma. Immunotherapy is often combined with other cancer treatments to boost its effectiveness. Some types of immunotherapy treatments are used in patients who haven’t responded to other types of cancer treatment.
Doctors who treat blood cancer are excited about the possibilities that immunotherapy has. “It treats the disease at its origin and not as a broad-spectrum treatment like chemotherapy,” Koehne says. The first immunotherapy, rituximab, was approved by the U.S. Food and Drug Administration in 1997.
However, there still needs to be more research to pinpoint how to make immunotherapy more effective and safer for patients, says Dr. Nicole Lamanna, a hematologist/oncologist and associate clinical professor of medicine in the hematologic malignancies section of the Hematology/Oncology Division at Columbia University Irvine Medical Center in New York City. That’s because immunotherapy is newer than traditional treatments, so it doesn’t have as much long-term research. And like many other cancer treatments, it also has side effects such as fatigue, fever and an increased risk for infection.
Types of Immunotherapy Used for Blood Cancer
There are several types of immunotherapy used for blood cancers:
— Checkpoint inhibitors.
— Bispecific antibodies.
Short for chimeric antigen receptor T-cell therapy, this approach takes immune cells called T-cells from a person with cancer and then combines them with a virus to teach those cells how to attach to cancer cells. The modified T-cells are then given to that person again after chemotherapy so they can attach to and kill the cancer cells. Success rates for CAR-T therapy vary depending on the type of cancer and how advanced it is. One type of blood cancer that responds well to CAR-T is acute lymphoblastic leukemia, Koehne says.
A 2018 study published in the Annals of Hematology compared the CAR-T therapy called tisagenlecleucel with chemotherapy in 92 patients with acute lymphoblastic leukemia and found a complete remission rate of 90.9% in the CAR-T group, versus 37.9% in the chemotherapy group. The survival rate at 12 months was 61% in the CAR-T group, versus 10% in the chemotherapy group.
This type of therapy uses antibodies from a person’s immune system to boost up a patient’s immune cells to help kill the tumor. They help the immune cells to work better and carry out their intended function of killing tumor cells, Samaneigo says. Hodgkin lymphoma is one type of blood cancer that can be treated with checkpoint inhibitors.
For instance, a checkpoint inhibitor called pembrolizumab led to the shrinking or disappearing of tumors in 65% of patients with Hodgkin lymphoma who did not respond to other previous treatments or who had their cancer return, according to a 2016 study in the Journal of Clinical Oncology. This study led to the approval of pembrolizumab to treat Hodgkin lymphoma.
The term bispecific antibodies are lab-engineered proteins that are developed to bind to two different antigens, substances that produce an immune response in the body — a sort of “boosted” antibody for killing cancer cells. Blinatumomab was the first bispecific antibody approved by the FDA for adult or pediatric patients with relapsed or refractory leukemia in 2017.
More types of immunotherapy are available and continue to emerge. There are also many drugs in development within each type of immunotherapy.
The frequency of immunotherapy will depend on the type of cancer you have and its severity. It also will depend on your body’s response to the therapy. You may get immunotherapy daily or weekly, or you may have a period of time with treatment and then a rest time to allow your body to respond to immunotherapy.
Your doctor will schedule regular checks to find out how your cancer is responding to immunotherapy and other treatments. This could include:
— Blood tests.
— Physical exams.
— Scans that examine the tumor size.
Side Effects of Immunotherapy for Blood Cancer
Just like other treatment for blood cancer, immunotherapy also can cause side effects. The side effects may differ depending on the type of immunotherapy used. The side effects from immunotherapy are less predictable compared with chemotherapy, Diefenbach says. Here are some of the typical side effects of immunotherapy for blood cancer:
— Autoimmune diseases such as arthritis or diabetes.
— Blood pressure changes.
— Body aches.
— Cytokine release syndrome. This syndrome is associated with CAR-T and has some serious symptoms, such as a high fever, heart dysfunction and liver failure. However, there are now medications used along with CAR-T to help prevent or treat cytokine release syndrome, Lamanna says.
— Higher risk of infection.
— Neurological toxicity. Also associated with CAR-T, this involves seizures, delirium and an inability to speak clearly. As with cytokine release syndrome, there are now medications available to help prevent neurological toxicity.
— Rash during or after intravenous use of immunotherapy.
Questions to Ask About Immunotherapy for Blood Cancer
If you have blood cancer and your doctor recommends immunotherapy, there are several questions you should ask:
— Do I need chemotherapy before my immunotherapy?
— How much experience does your hospital have with immunotherapy? You should get treated by a medical center that can offer both traditional and cutting-edge treatments such as immunotherapy, Diefenbach advises.
— How is immunotherapy different from other therapies?
— What are the risks and benefits of immunotherapy for me?
— What side effects are part of this treatment?
— What is the chance of remission or cure of my cancer with this therapy?
— What clinical trials might be helpful for me? There are many ongoing trials for immunotherapy right now.
— Will my insurance cover immunotherapy?
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