September is Blood Cancer Awareness Month, a time to raise awareness about this serious disease and its impact on patients and families. Blood cancer is a severe disease, but treatment has advanced significantly in recent years.
Understanding Blood Cancer
Blood cancer is a group of diseases in which abnormal blood cells are produced in the bone marrow or from blood cells that were derived from the bone marrow residing in other locations. Blood cancers come in a variety of forms and each type affects a different type of blood cell and has distinct symptoms or treatment options.
● Leukemia is a cancer of the bone marrow’s blood-forming cells. It has the potential to harm normal white blood cells, red blood cells, and platelets. The most common type of blood cancer in children is leukaemia.
● Lymphoma is a type of cancer that affects the lymph nodes, which are small bean-shaped organs that aid the body in fighting infection. Lymphoma comes in many varieties and can affect people of all ages.
● Myeloma is a type of cancer that affects plasma cells, which are white blood cells that produce antibodies. Myeloma is most prevalent in people over the age of 60.
Immunotherapy is a type of cancer treatment that employs the body’s own immune system to combat the disease. Many different types of blood cancer, including leukaemia, lymphoma, and myeloma, have been shown to benefit from this type of treatment. CAR-T cell therapy is one type of immunotherapy used to treat blood cancer. CAR-T cell therapy involves genetically engineering patient’s own T cells (a type of white blood cell) to target cancer cells. These altered T cells are then reintroduced into the patient’s body, where they attack and kill cancer cells. This is like a live drug which keeps continuously fighting the cancer keep it at bay.
Another form of immunotherapy is using antibodies which are natural proteins produced by our body to fight infections to target cancer cells. For example, in B cell lymphoma Rituximab, an antibody that recognises cancer cells expressing CD20 antigen significantly improves the cure rate without major side effects.
2. Targeted Therapies: Precision Medicine for Blood Cancer
A type of treatment that targets specific molecules involved in cancer growth is known as targeted therapy. Traditional chemotherapy, which targets all rapidly dividing cells, including healthy cells, is effective but has major side-effects because of the collateral damage it causes to normal cells. Imatinib is one example of a targeted therapy used to treat blood cancer. Imatinib is a drug that targets the BCR-ABL protein, which is found in chronic myeloid leukaemia (CML). Imatinib has been shown to be very effective in the treatment of CML, assisting many patients in achieving long-term remission.
3. Advancements in Stem Cell Transplants
Stem cell transplants are a type of treatment in which a patient’s diseased bone marrow is replaced with healthy stem cells. This can be done with either a donor or the patient’s own bone marrow. Stem cell transplantation is frequently used to treat blood cancer, particularly leukaemia. In leukaemia not only this treatment eradicates the cancer and the new immune system derived from donor significantly impairs the chances of leukaemia coming back. Other diseases, such as multiple myeloma stem cells from the patient are used to allow higher doses of chemotherapy to be administered which would not be otherwise possible.
4. Innovative Drug Combinations
There has been an increase in interest in using combination therapies to treat blood cancer in recent years. This method entails combining two or more different types of treatment. Combination therapies may be more effective than single-agent treatments, and they may also aid in the reduction of resistance and side effects.
5. Gene Editing and Blood Cancer
Gene editing is a relatively new technology that enables scientists to make precise changes to genes. This technology is being researched for a variety of applications, including blood cancer treatment.
Targeting genes involved in cancer growth is one-way gene editing could be used to treat blood cancer. Scientists could potentially stop cancer cells from growing and spreading by editing these genes. Gene editing technology is also used to manufacture CAR-T cells which is a type of immunotherapy.
6. Antibody drug conjugates (ADC)
ADC’s are where a monocolonal antibody is linked to a chemotherapeutic drug. As the antibody has a specific target and if the target is the cancer cell the antibody (vehicle) delivers the chemotherapeutic agent (payload) directly and specifically to the cancer cell there by avoiding damage to the normal cells. For example, Inotuzumab ozogamicin is once such drug used to treat blood cancer.
7. Bispecific T cell engager (BiTE)
BiTE’s are a class of artificial monoclonal antibodies which can bring two cells together. Normally naturally occurring antibodies will have single specificity. For example, Blinatumomab is a bi-specific T cell engager which brings the cancerous B cell with normal immunocompetent T cell together so that T cells recognise the cancer and starts attaching it.
All these newer forms of treatment increase the chances for cure in the future and brings a lot of hope for further improvements in already promising progress in the fight against blood cancers in the modern era.
Authored by Dr. Stalin Ramprakash, Sr. Consultant – Paediatric Haematology, Oncology & BMT, Aster CMI Hospital, Bangalore