Explaining bone marrow, its cancer and treatment!

Dr Dinesh Bhurani, Director, Hemato-Oncology and BMT, Rajiv Gandhi Cancer Institute and Research Center, New Delhi explains all the basics about bone marrow, its cancer and the kind of treatment that would work best in the patients

0
45
Download PDF

Bone marrow is a soft, spongy tissue inside our bones that makes blood-forming cells (blood stem cells). These cells turn into blood cells including white blood cells to fight infections. Red blood cells are known to carry oxygen throughout the body. Bone marrow cancer affects more than one area of our body.

The two types of bone marrow are red bone marrow, called myeloid tissue, and yellow bone marrow, or fatty tissue. Red bone marrow consists of a delicate, highly vascular fibrous tissue containing hematopoietic stem cells also known as blood-forming stem cells.

Yellow bone marrow contains mesenchymal stem cells also recognized as marrow stromal cells are responsible for producing fat, cartilage, and bone. Doctors suggest that stem cells are small cells that can change into a number of different types of cell.

Hematopoietic stem cells in the bone marrow increase to two main types of cells: myeloid and lymphoid lineages. These include monocytes, macrophages, neutrophils, basophils, eosinophils, erythrocytes, dendritic cells, and megakaryocytes or platelets, as well as T cells, B cells, and natural destroyer cells. The different types of hematopoietic stem cells differ in their reproductive capacity and strength. Some are multipotent, oligopotent or unipotent as determined by how many types of cell they can create.

Pluripotent hematopoietic stem cells contain can replicate another cell identical to themselves. These cells are responsible for generating one or more subsets of more mature cells.

What happens when bone marrow gets cancer?

Cancer is a harmful disease and it becomes worse when it starts growing in the bone marrow. There are several symptoms of bone marrow cancer such as bone pain and easily broken bones. People diagnosed with this disease may also have frequent infections and fevers, excessive thirst, or increased urination. Additionally, nausea, weight loss, and constipation may occur. There are various types of bone marrow cancers such as:

Multiple Myeloma: This is the most usual type of bone marrow cancer that affects plasma cells. These are white blood cells that help fight infection and disease. In multiple myeloma, cancerous plasma cells move out normal, healthy ones and destroy or weaken/destroy the bones.

Lymphomas: These generally start in lymph nodes, but they can begin in the bone marrow. Non-Hodgkin’s lymphoma begins in the lymphocytes, a type of white blood cell that can live in the bone marrow.

Leukemia: If you have this type of cancer, your body makes abnormal blood cells that can’t fight infection or prevent bleeding. Usually, it forms in the white blood cells, but it can occur in other types of cells, too. It can be either fast-growing (acute) or slow-growing (chronic). There are many types of leukemia. All of them have different treatments.

Childhood Leukemia: This is the most usual form of cancer in children and youth. About 3 out of every 4 childhood-leukemias are sensitive lymphocytic leukemia. This forms in newly formed white blood cells and progresses quickly. The rest are usually acute myeloid leukemia. This type of cancer moves quickly into the blood and can spread to other parts of the body, easily.

To reduce the risk of the bone marrow cancer doctors and experts suggest for bone marrow transplant therapy. It is a special therapy for people diagnosed with certain cancer or other diseases. A bone marrow transplant includes taking cells that are usually found in the bone marrow (stem cells), filtering those cells, and giving them back either to the donor (patient) or to another person. The aim of bone marrow therapy is to transfer healthy bone marrow cells into a person after his or her own harmful bone marrow has been treated to kill the abnormal cells. In past bone marrow transplant has shown successful results. This is not all bone marrow transplant has been used successfully to treat diseases such as leukemias, lymphomas, aplastic anemia, immune deficiency disorders, and some solid tumour cancers since 1968.

Why bone marrow transplant is needed and what are the benefits?

A bone marrow transplant is usually recommended to replace diseased, non-functioning bone marrow with healthy functioning bone marrow (for conditions such as leukemia, aplastic anemia, and sickle cell anemia). Besides this, through this therapy, the patient can have a new immune system because this therapy regenerates a fresh new immune system in a human body that will fight existing or residual leukemia or other cancers not killed by the chemotherapy or radiation used in the transplant.

Moreover, with the help of bone marrow transplant the bone marrow also get replaced and restored to its normal function after the high doses of chemotherapy and/or radiation are given to treat a malignancy. This process is often called rescue (for diseases such as lymphoma and neuroblastoma.

About Author: Dr Dinesh Bhurani, Director, Hemato-Oncology and BMT, Rajiv Gandhi Cancer Institute and Research Center, New Delhi.