Blood cancer is a serious group of diseases. It affects the blood, bone marrow, and lymphatic system, which are all integral parts of the body’s ability to produce blood cells and fight infections. Rather than a single condition, blood cancer encompasses various distinct types, each with unique characteristics.
Understanding Blood Cancer
Blood cancer develops when abnormal blood cells grow uncontrollably, disrupting the normal function of healthy blood cells. This process originates in the bone marrow, the soft, spongy tissue inside bones where blood cells are produced. These abnormal cells can then spill into the bloodstream or affect the lymphatic system, a network of tissues and organs that helps rid the body of toxins and waste.
Healthy blood consists of red blood cells, which carry oxygen; white blood cells, which fight infection; and platelets, which help blood clot. In blood cancer, the cancerous cells multiply unchecked, crowding out the healthy cells and preventing them from functioning. This leads to a shortage of normal blood cells, impairing oxygen transport, pathogen defense, and bleeding control. The underlying cause is a mutation or change in the DNA within blood cells, causing them to behave abnormally.
Main Forms of Blood Cancer
The term “blood cancer” covers three main categories: leukemia, lymphoma, and myeloma, each affecting different blood cell types or parts of the blood-forming and immune systems. These distinctions are based on the cell type involved and where the cancer originates.
Leukemia begins in the blood and bone marrow, marked by overproduction of abnormal white blood cells. These cancerous white blood cells, often immature, crowd out healthy blood cells, hindering the bone marrow’s production of red blood cells and platelets. Leukemia is classified as either acute, progressing rapidly, or chronic, with a slower growth pattern. Subtypes include acute myeloid leukemia (AML), more common in older adults, and acute lymphocytic leukemia (ALL), more common in children.
Lymphoma develops in the lymphatic system, affecting lymphocytes, a white blood cell type crucial to the immune system. These cancerous lymphocytes can form tumors in areas like the lymph nodes, spleen, or thymus gland. It divides into two main types: Hodgkin lymphoma, characterized by Reed-Sternberg cells, and non-Hodgkin lymphoma, a broader range without these cells.
Myeloma, often referred to as multiple myeloma, affects plasma cells, specialized white blood cells in the bone marrow that produce antibodies. In myeloma, abnormal plasma cells accumulate in the bone marrow, interfering with healthy blood cell production and damaging bones, weakening the immune system. It is termed “multiple” because it frequently affects several sites within the bone marrow.
How Blood Cancer is Identified
Identifying blood cancer often begins with recognizing common signs and symptoms. These can include persistent fatigue, unexplained weight loss, recurrent fevers or chills, easy bruising or bleeding, and swollen lymph nodes in the neck, armpits, or groin. Shortness of breath, frequent infections, or bone and joint pain may also be present. These symptoms can also indicate less serious conditions, so medical evaluation is necessary for an accurate diagnosis.
Diagnosis starts with blood tests, such as a complete blood count (CBC), checking for abnormal levels of red blood cells, white blood cells, and platelets. A blood chemistry test may also detect unusual proteins in the blood. If these tests suggest a problem, a bone marrow biopsy may be conducted, involving a small sample of bone marrow from the hip bone. This sample is then examined under a microscope to identify abnormal cells or genetic mutations.
For suspected lymphoma, a lymph node biopsy is necessary, where a sample of lymph tissue or an entire lymph node is removed for analysis. Imaging scans, such as CT, PET, and MRI scans, can also detect enlarged lymph nodes or assess if cancer has affected other body parts. Flow cytometry, a specialized test, detects cancer cells in bone marrow or blood by identifying specific protein markers.
Managing Blood Cancer
Managing blood cancer involves various treatment approaches, tailored to the cancer’s type and stage, and the patient’s overall health. The goal of treatment is to slow, stop, or eliminate the cancer and manage associated symptoms.
Chemotherapy
Chemotherapy uses drugs to kill cancer cells throughout the body. These drugs are administered intravenously or orally, with different types used for different blood cancers.
Radiation Therapy
Radiation therapy uses high-energy rays, like X-rays, to damage cancer cell DNA, preventing multiplication. It can be used alone or in combination with other treatments, and may alleviate pain.
Targeted Therapy
Targeted therapy focuses on specific weaknesses in cancer cells related to genetic mutations, blocking their growth and spread. Distinct from chemotherapy, these treatments are given orally or intravenously.
Immunotherapy
Immunotherapy works by boosting the immune system to fight cancer. Examples include monoclonal antibodies and CAR T-cell therapy, enhancing the immune system’s ability to recognize and destroy cancer cells.
Stem Cell Transplantation
Stem cell transplantation, also known as bone marrow transplantation, involves replacing diseased blood-forming stem cells with healthy ones. This procedure follows high-dose chemotherapy to destroy abnormal stem cells. There are two main types: autologous transplants use the patient’s own healthy stem cells, collected and stored before treatment, while allogeneic transplants use stem cells from a donor.