What Is Bone Marrow Cancer?

Bone marrow is the tissue in the center of bones that produces blood cells. Cancers that develop in the bone marrow include leukemia, which affects the infection-fighting white blood cells, multiple myeloma, which affects the plasma cells, and myelodysplastic syndromes (MDS), which can keep blood cells made by the bone marrow from becoming mature.

In addition, there are myeloproliferative neoplasms (MPN) that may be benign (noncancerous), precancerous, or cancerous. This article will review the types of bone marrow cancer, how they are diagnosed, treated, and how to cope if you’ve been diagnosed with one. 

Types of Bone Marrow Cancer

There are several types of bone marrow cancer, each affecting the different types of blood cells produced by the bone marrow.

Leukemia is a type of cancer affecting white blood cells and can be acute or chronic. Acute leukemias grow quickly, whereas chronic leukemias grow more slowly. Examples of leukemia include:

• Acute lymphoblastic leukemia
• Acute myeloid leukemia
• Chronic lymphocytic leukemia
• Chronic myelogenous leukemia

Multiple myeloma is a cancer that affects the plasma cells, which are responsible for producing antibodies to help the body fight infection.

Myelodysplastic syndromes (MDS) are a group of disorders that affect the production of blood cells in the bone marrow. The blood cells don’t grow to the full maturity they are supposed to, which results in them not working properly.

Examples of types of MDS include:

• Refractory anemia
• Refractory anemia with ringed sideroblasts
• Refractory anemia with excess blasts
• Refractory cytopenia
• Unclassifiable MDS

Myeloproliferative neoplasms are a group of diseases in which too many of a certain type of cell (white blood cells, red blood cells, or platelets) are made. The abnormal growth of these cells can prevent them from working properly and can lead to other problems. These conditions may be benign, precancerous, or cancerous.

The types of MPN include:

• Polycythemia vera (too many red blood cells)
• Primary myelofibrosis (progressive scarring of the bone marrow)
• Essential thrombocythemia (too many platelets)

Chronic leukemias may also be classified in this group.

Bone Marrow Cancer Symptoms

Symptoms of bone marrow cancers can differ depending on the type and stage of the cancer. However, some common symptoms of bone marrow cancers can include:

• Fatigue
• Weakness
• Unintentional weight loss
• Frequent infections
• Fever
• Bone pain
• Joint pain
• Easy bruising or bleeding

In some cases, no symptoms may be present or may be so mild they aren’t noticed or are attributed to something else. Additionally, symptoms other than the ones listed above may be present, depending on the type of cancer. 

Causes

Cancer develops when the DNA (genetic material) in the affected cells becomes abnormal in some way. In many cases, the exact cause of these cancers is not fully understood. But there are known risk factors that can increase someone’s chance of developing these cancers.

Risk factors for developing leukemia can vary somewhat depending upon the type. However, common risk factors include:

• Exposure to radiation
• Exposure to chemicals such as benzene
• Family history of leukemia
• Increasing age
• Smoking
• Having other bone marrow disorders
• Having genetic disorders such as Klinefelter's syndrome or Li-Fraumeni syndrome

Risk factors for developing multiple myeloma include:

• Increasing age
• Exposure to radiation
• Family history of myeloma
• Male sex

Multiple myeloma is diagnosed more often in Black people.

Risk factors for MPN and MDS are similar and  include:

• Family history of MPN or MDS
• Increasing age
• Exposure to radiation
• Exposure to benzene
• Presence of a Janus kinase 2 (JAK2) mutation
  

Diagnosis

The diagnosis of bone marrow cancers requires multiple steps, often starting with a medical history and physical examination by a healthcare provider.

Laboratory tests may be taken to evaluate the complete blood count (CBC). This test provides a result of the numbers of white blood cells, red blood cells, and platelets, as well as abnormalities in the shape and size of blood cells. Additional blood testing can evaluate kidney and liver function, electrolytes, and more.

If indicated, a bone marrow biopsy may be performed. This involves removing a small amount of bone marrow tissue and examining it under a microscope. This can determine any abnormalities within the bone marrow, and further testing of the marrow can look for genetic changes or mutations.

Imaging studies such as computed tomography (CT) scans or positron-emission tomography (PET) scans can help identify the extent of the cancer and if it has spread to other parts of the body.

Treatment

Once the diagnosis is made, and all blood and imaging tests have been completed, the healthcare provider will determine the best treatment plan. The treatment of bone marrow cancers can vary depending on the specific type and stage of cancer. Some common treatments include:

• Chemotherapy: Uses medications to kill fast-growing cells, including cancer cells
• Radiation therapy: Uses high-energy radiation to destroy cancer cells
• Bone marrow or stem cell transplantation: Replaces cancerous bone marrow with healthy cells from the person or a donor
• Immunotherapy: Uses the immune system to help fight cancer cells
• Targeted therapies: Specifically target certain proteins or genes that contribute to the growth and spread of cancer cells.

The choice of treatment may also depend on the person's age and overall health. In some cases, depending on the type of cancer, no treatment other than observation may be indicated. In this instance, it is called watchful waiting.

Prognosis 

The prognosis for people living with bone marrow cancers can vary widely depending on the type and stage of cancer, as well as the person's overall health. Some types, such as chronic lymphocytic leukemia, have a relatively good prognosis, while others, such as acute myeloid leukemia, have a poorer prognosis. 

Prognosis is also affected by other factors, such as age, the presence of certain genetic mutations, and the response to treatment. Over the years, as treatment options have improved, prognosis has improved for some types of bone marrow cancer.

Coping 

Coping with bone marrow cancer can be difficult for the individual and their loved ones. Those living with bone marrow cancer need a support system of family, friends, and healthcare providers to help them through the emotional and physical aspects of the disease.

Some may find benefits in joining a support group to share their thoughts and feelings. Open and honest communication is so important for a person to maintain with their healthcare provider to ensure they receive the best possible care and support throughout their cancer journey.

Summary

Bone marrow cancers are a disease of the cells of the bone marrow, which make white blood cells, red blood cells and platelets. When these cells develop abnormally, cancer can grow. There are multiple types of bone marrow cancers, and the treatment and prognosis can vary for each.