Blood clots can be a side effect of both lung cancer and the drugs you take to treat it. It’s important to know the warning signs of a clot and get medical attention right away if you think you have one.
Blood clots serve a vital purpose when you’re injured. After a cut, tiny cell fragments called platelets rush to the site, forming a protective seal to stop bleeding.
However, some blood clots form unnecessarily and dangerously, blocking vessels in critical areas like the brain or lungs and interrupting essential blood flow.
Lung cancer can increase the risk of blood clots inside your deep veins. This is called venous thromboembolism (VTE).
People with cancer are 4 to 7 times more likely to develop a clot than people without cancer. Cancer is responsible for about 1 out of every 5 cases of VTE.
Deep vein thrombosis (DVT), a specific type of VTE, occurs when a clot forms in one of your leg’s deep veins and requires immediate attention.
A DVT blood clot can break loose and travel to the lungs. This is called a pulmonary embolism (PE), and it can be fatal if it blocks blood supply.
These clots may also reach the brain, triggering a stroke.
Up to 20% of people with cancer will develop a blood clot. These painful and serious complications require prompt treatment. Blood clots are the
Cancer cells damage healthy tissues as they multiply and spread.
When your body detects damage, it sends platelets and clotting factors to repair it. This natural repair process includes forming clots to stop excess bleeding.
Cancer thickens your blood and releases the sticky clot-forming proteins. Tumors can also press on blood vessels, blocking blood flow. When blood flow slows, clots are more likely to form.
Certain people with lung cancer are more likely to develop blood clots, including those with:
- non-small cell lung cancer (NSCLC)
- adenocarcinoma
- stage 3 or 4 lung cancer
- chemotherapy or surgery to treat their cancer
Other factors that can increase blood clot risk include:
- personal or family history of blood clots
- limited physical activity
- extended hospital stays
- having a central line (a catheter placed in a large vein)
- using tobacco products, including cigarettes, vaping, or other forms
Some cancer treatments also raise blood clot risk. Chemotherapy can damage blood vessel walls and trigger clot formation.
Specific treatments known for causing clots include platinum-based chemotherapy drugs such as cisplatin and the targeted drug bevacizumab (Avastin).
Lung cancer surgery is another risk factor. During operations, blood can pool in your veins when you’re unable to move, leading to clots.
Hospitals should implement special measures to prevent blood clots following surgery.
Blood clots don’t always cause noticeable symptoms. When symptoms do occur, they may include:
- swelling, warmth, or pain in the back of the calf and thigh
- redness or other skin color changes
- chest pain that worsens with deep breathing
- rapid heart rate
- sudden shortness of breath
- coughing up blood
These symptoms require immediate medical attention. If you experience any of these symptoms, call 911 or go to an emergency room right away. Medical professionals can confirm the presence of blood through blood tests, CT scans, or ultrasound imaging.
If you have a clot, doctors can give you medication to dissolve it and prevent new clots from forming. These medications will help you heal while your body dissolves the clot.
Having a higher risk of blood clots means you should take preventive measures, not that clots are inevitable. You can reduce your risk with several practical approaches.
Limit extended periods of sitting by taking regular breaks to stand or stretch, if possible. Avoid crossing your legs for long periods because this can restrict blood flow.
You may need blood-thinning medications such as heparin to prevent clot formation. When making this decision, your doctor will balance your clotting risk against the potential bleeding risks from blood thinners.
After lung cancer surgery, when clot risk is higher, you may temporarily need blood thinners. Also, compression stockings or socks can help maintain blood circulation in your legs during recovery, reducing the likelihood of clot formation.
While your primary focus during cancer treatment is fighting the disease itself, being aware of blood clot risks remains essential.
If your doctor doesn’t discuss blood clots, consider bringing it up. Ask about your risk and how to avoid developing a clot.
Be alert for symptoms like swelling and pain in your leg and get medical help right away if you have them.