Thrombocytopenia & Other Bleeding Disorders

Blood clotting, or coagulation, is a normal process that prevents excessive blood loss when you have a cut or an injury. Platelets combine with specialized proteins in the blood called clotting factors, forming clots that stop bleeding at the injured site. These small clots eventually dissolve after your injury heals. People who have an abnormally low level of clotting factors or platelets have a higher risk of bruising and excessive bleeding, especially after an injury or surgery.

The following are some causes of cancer-related bleeding disorders:

  • Antiangiogenesis drugs, which prevent the growth of new blood vessels that nourish tumors, can increase the risk of bleeding.
  • Certain cancers can increase the risk of bleeding. Cancer in the liver — either a primary liver tumor or metastatic cancer that has spread to the liver from elsewhere in the body — can decrease the production of clotting factors.

Having a preexisting condition that decreases the production of clotting factors or platelets can also increase some patients’ risk of bleeding. Some bleeding disorders are hereditary, but remain undiagnosed until several family members experience bleeding problems during surgery or trauma.


Another common type of bleeding disorder is called thrombocytopenia. Thrombocytopenia is a dangerous drop in the number of platelets in the blood that can increase a person’s risk of bleeding.

Thrombocytopenia does not occur only in people with cancer. However, it is a common side effect of cancer treatment that occurs when chemotherapy drugs damage bone marrow — where platelets are made — or speed up the destruction of platelets in the bloodstream, liver, or spleen.

Hematologists at Memorial Sloan Kettering are experts in the diagnosis and management of thrombocytopenia, whether it is a side effect of cancer treatment or results from other causes.


Many people who have a bleeding disorder — regardless of whether it is caused by an underlying condition, cancer, or cancer therapy — do not notice symptoms until they experience an injury or until a doctor detects excessive bleeding in the operating room. Some patients may have symptoms such as increased bruising or blood in their vomit or stool. Tell your doctor if you notice any of these symptoms.

Treating Bleeding Disorders

If you have an underlying bleeding disorder or have been given anticoagulant or thrombolytic medications to prevent the formation of blood clots, our hematologists and nurses will monitor your blood to determine if you are at risk of excessive blood loss during surgery or other procedures. If your blood does not have enough clotting factors, your doctor may recommend infusions of clotting factors, blood plasma, or platelets from donated blood.

If you have a low platelet count due to an immune condition called idiopathic thrombocytopenic purpura (ITP), our doctors will develop an individualized treatment plan that uses state-of-the-art treatments and is tailored to your specific condition.

Before treatment, our blood specialists work with your primary treatment team to screen for bleeding problems, including inherited conditions such as Von Willebrand disease and hemophilia as well as acquired disorders.