Myelosuppression

Myelosuppression occurs when the bone marrow makes too few blood cells to replace the spent blood cells. Myelosuppression is not a painful condition, but it is a serious one, can it can lead to fatigue, excessive bleeding, or an increased vulnerability to certain infections.

These three conditions are a direct result of reduced bone marrow production, as they reflect the shortage of specific blood cells with specific purposes:

-- Anemia is due to a shortage of red blood cells and causes fatigue.

-- Thrombocytopenia, or excessive bleeding, occurs when there is a shortage of platelets.

-- Neutropenia is defined as a shortage of white blood cells, notably neutrophils, and it leaves patients open to the risk of serious infection.

Causes of Myelosuppression

In the context of cancer treatment, myelosuppression is generally a consequence of anti-cancer treatment like chemotherapy. You can look at the side effects of almost any major chemotherapy drug and see 'myelosuppression' listed. Though a serious condition, it is typically not permanent, and when anti-cancer treatments cease, the bone marrow usually returns to its normal production of blood cells.

When cancer treatment causes myelosuppression, the next step is typically at the discretion of the patient's physicians. Responding to myelosuppression may involve halting chemotherapeutic treatment to allow the bone marrow to recover; it may involve a red blood cell transfusion to overcome the effects of anemia, or it may involve an injection of so-called growth factors, that encourage the bone marrow to produce neutrophils.

If myelosuppression is mild, and the patient is not affected, there may be no intervention at all. The decision would be made by the patient's oncology team based on their specific set of circumstances.

To that end, sometimes myelosuppression is treated in a prophylactic manner—meaning before it begins. This can be achieved by using the likes of granulocyte colony-stimulating factor (G-CSF) which can sometimes reduce the severity of the distress on the bone marrow from cancer treatment.

Sources

- Medscape: Chemotherapy-Induced Myelosuppression
- American Cancer Society: Bone marrow suppression