Can Lung Cancer Cause Blood Clots?

If you have been diagnosed with lung cancer, you likely understand that your immune system is weakened, making you highly susceptible to other medical conditions. For example, lung cancer can increase your risk of blood clots. In fact, if you have lung cancer, your risk for blood clots increases by four to seven times the amount compared to people without cancer. Up to 25 percent of cancer patients will develop blood clots during their lifetime.

Blood clots are often described as deeply painful and appear as a swollen, red area on the skin. You may also experience shortness of breath, increased heart rate, hemoptysis, and other associated symptoms. In severe cases, you may even experience a pulmonary embolism. A pulmonary embolism is a sudden blockage in your pulmonary arteries, which send blood to your lungs.

The deadly mineral asbestos often leads to the development of lung cancer. This connection means that if you were exposed to asbestos, you might have an increased risk of cancer and clotting. Understanding the symptoms and causes of these blockages is essential as blood clots are the second leading cause of death in cancer patients, after cancer itself. Learn about blood clots, their symptoms, deep vein thrombosis, and venous thromboembolism.

What is a Blood Clot?

The body engages in a normal bodily process called coagulation, which involves clotting the blood. When you experience a cut or injury, your body goes into action to prevent excessive blood loss through a process called coagulation. Platelets and proteins in your blood gather at the site of the injury and form a clot, which can be seen as a scab or dried clump of blood. This natural response helps to stop bleeding and allows the area to heal over time. It’s important to note that these types of blood clots are normal and nothing to worry about.

Although there is normal blood clotting, there are many other types of coagulation, named by the area they affect, including:

  • Thrombus (single) or thrombi (multiple).
  • Disseminated intravascular coagulation (DIC): A condition that is a complication of cancer that causes severe flooding and severe clotting simultaneously.
  • Thromboembolism: A thrombus that has broken loose and stuck in another blood vessel.
  • Deep vein thrombosis (DVT): A blood clot that occurs in a deep vein, such as in the arm or leg.
  • Pulmonary embolism (PE): A blood clot that has started elsewhere but breaks loose and sticks in the lungs.
  • Venous thromboembolism: A word used to describe both DVT and PE.

Infographic showing a healthy vein, a regular blood clot, and deep vein thrombosis with a leg with veins

Cancer itself and its associated treatment options can lead to the development of blood clots. Some cancers pose a higher risk for clotting, including cancers of the:

  • Pancreas
  • Stomach
  • Brain
  • Lungs
  • Uterus
  • Ovaries
  • Kidneys
  • Blood

A doctor may detect blood clots during a regular physical exam or if you are experiencing lung cancer symptoms. To formally diagnose blood clots, you may undergo a duplex ultrasound, an imaging test used to sound waves of blood flow, or a blood test, which detects clot formation. Once you receive your diagnosis, you will likely undergo treatment. Standard therapy options for blood clots include blood-thinning medications, thrombolysis, surgery, inferior vena cava filter placement, or clot dissolvers. Consult with your doctor to receive more tailored treatment for your blood clots.

What is Deep Vein Thrombosis (DVT)?

Deep vein thrombosis (DVT) occurs when a blood clot forms in one or more of the body’s deep veins, such as in the legs, arms, thigh, or pelvis. DVT usually occurs if you have certain medical conditions affecting blood clots, like lung cancer and mesothelioma, which affects the lungs. Additionally, a blood clot in the legs is more likely to develop if you do not move for a long time, like if you are bedridden.

DVT itself is not life-threatening. Half of those who develop DVT in their legs develop leg pain and swelling that can last years. These symptoms, called post-thrombotic syndrome, can occur due to damaged valves and the inner lining of your veins, leading to blood pooling more than it should. Common symptoms of DVT include blood pooling, swelling, increased pressure within your veins, increased pigmentation or discoloration, or ulcers. Unfortunately, deep vein thrombosis can have no noticeable symptoms other than swelling and pain, meaning it can go undiagnosed and untreated.

Deep vein thrombosis can become more severe when those blood clots break loose in the veins. When this occurs, the thrombi can travel through the bloodstream and get stuck in the lungs, blocking blood flow and resulting in pulmonary embolism. When these two clots occur in conjunction, doctors call it venous thromboembolism (VTE).

What is Venous Thromboembolism (VTE)?

Venous thromboembolism (VTE) is a significant vascular condition, ranking as the third most common diagnosis following a heart attack and stroke, and it affects a considerable number of Americans annually, ranging from 300,000 to 600,000 individuals. While VTE can potentially affect anyone, certain populations are more likely to develop this condition. These include:

  • Individuals over the age of 60: Advancing age is a contributing factor to the increased likelihood of VTE.
  • Overweight individuals: Excess weight can predispose individuals to VTE due to the impact on blood circulation.
  • Cancer patients: Cancer itself and certain cancer treatments can disrupt the body’s normal clotting mechanisms, making cancer patients more susceptible to VTE.
  • People with thick blood: Conditions such as hypercoagulability, where the blood has a higher tendency to clot, can increase the risk of VTE.
  • Pregnant or recently pregnant women: Pregnancy and the postpartum period can alter blood flow and increase the risk of clot formation.
  • Women on contraceptives or hormones: Some hormonal medications, including contraceptives, can affect blood clotting factors and raise the risk of VTE.

When treating DVT, PE, and VTE, the primary goal is to prevent further blood clot formation and break up existing clots. One common treatment option is the use of anticoagulant medications, which help dissolve blood clots and can be administered through injections or taken orally as tablets. Another approach to treating VTE is thrombolytic therapy, involving the use of clot-dissolving drugs such as tissue plasminogen activator (tPA). These medications are typically administered intravenously either through an arm vein or via a catheter inserted into a vein or lung.

What Stage of Lung Cancer Causes Blood Clots?

During lung cancer, the blood may become more prone to clotting, increasing the likelihood of developing a blood clot. This is especially true in later stages of cancer, such as stage three and stage four lung cancer. A recent study found that lung cancer patients have the highest likelihood of coexisting with a blood clot in the lungs, and doctors typically diagnose blood clots in the lungs within six months of diagnosing lung cancer.

One of the most concerning complications associated with lung cancer is hypercoagulability, which is when the blood has a higher tendency to form clots. This occurs because cancer cells release substances that promote clotting, and the cancer itself can trigger changes in the blood vessels and blood formation, leading to abnormal clotting. Tumors can compress blood vessels, impeding blood flow and increasing the risk of clot formation, making it another potential cause of blood clots.

Like later stages of cancer increase the risk of developing blood clots, some cancer treatments can increase the risk of clotting. These treatments can damage blood vessels or affect the natural balance of clotting factors. Cancer treatments that can cause blood clots include:

  • Chemotherapy
  • Lenalidomide
  • L-asparaginase
  • Platinum, such as cisplatin
  • Radiation therapy
  • Surgery
  • Tamoxifen
  • Thalidomide
  • Vascular endothelial growth factor (VEGF) inhibitors, such as bevacizumab
  • VEGF tyrosine kinase receptor inhibitors, such as sorafenib or sunitinib

Symptoms Associated with Lung Cancer and Mesothelioma

Mesothelioma and lung cancer are not only associated with various side effects such as fatigue, dry cough, and lung infections but can also increase the risk of developing blood clots. If you have received a diagnosis of either of these debilitating diseases, it is important to be aware of the heightened likelihood of blood clot formation. If you are experiencing symptoms like swollen legs or pain in your arms, it is crucial to consult with your doctor for appropriate testing to evaluate the presence of blood clots, including VTE and PE.

During this challenging period, seeking guidance from a cancer expert who can provide valuable support and assistance is recommended. Our team of knowledgeable professionals is available to connect you with leading cancer doctors, reliable attorneys specializing in related legal matters, and support groups, regardless of your location. We understand the importance of receiving comprehensive care and support and are here to help you navigate this difficult time.