Medically reviewed by Michelle Nguyen, MD, FACS, RPVI, on May 12, 2025
There is no scientific evidence that varicose veins—or their root cause, chronic venous insufficiency—lead to or result from cancer. These are two distinct conditions with separate causes and mechanisms. Still, if you're living with cancer or supporting someone who is, concerns about blood clots or worsening vein symptoms are valid. Understanding the connection between cancer treatments and vascular health is essential to staying safe and well-informed.
This article, medically reviewed by Center for Vein Restoration (CVR) vein specialist Dr. Michelle Nguyen, explains how cancer and its treatments can affect your veins, especially if you already have vein disease, and what you can do to reduce your risk of complications such as blood clots. Dr. Nguyen is the lead vein physician in CVR vein clinics in Manassas, Virginia, and Reston, Virginia.
If you’re managing cancer or living with varicose veins, sudden leg pain or swelling can be alarming. But you don’t have to wait in a crowded emergency room to get the answers you need. Center for Vein Restoration (CVR), America’s largest physician-led vein care center, offers an office-based DVT rule-out service, providing fast, expert evaluation for suspected blood clots—so you can get peace of mind or prompt treatment without delay.
Contact your primary care provider, who can call 877-SCAN-DVT (877-722-6388) today to schedule a DVT screening and protect your health. Remember: every moment matters when it comes to blood clots.
Varicose veins are enlarged, twisted veins that typically appear in the legs. They form when the valves inside your leg veins weaken or become damaged. Instead of pushing blood back toward your heart, the faulty valves allow blood to pool in the veins. This condition is known as chronic venous insufficiency (CVI), a common form of vein disease.
Varicose veins can cause a wide range of symptoms, including:
Although varicose veins are sometimes dismissed as a cosmetic issue, they can indicate underlying vein problems that deserve medical attention.
Don't ignore the signs your legs are sending you! At Center for Vein Restoration (CVR), our board-certified vein doctors specialize in diagnosing and treating chronic venous insufficiency with personalized, minimally invasive care. Find a CVR vein clinic near you.
Questions? Call 240-965-3915 to speak with a CVR Patient Services Representative or schedule your consultation online at a CVR near you today.
Varicose veins do not cause cancer, and cancer does not directly cause varicose veins. However, cancer and its treatments can have an impact on vascular health, and that’s where the connection lies.
People with cancer, especially those undergoing chemotherapy or recovering from surgery, are at greater risk of developing blood clots. According to the Centers for Disease Control and Prevention (CDC), cancer patients have a significantly higher risk of deep vein thrombosis (DVT)—a blood clot in a deep vein, usually in the legs. As many as 50 percent of cancer patients with a central venous catheter for long-term chemotherapy get a DVT.
This risk is significant for people who already have vein disease. Weakened veins that aren’t moving blood efficiently are more likely to become sites where clots form, especially when cancer or its treatment adds extra strain to the vascular system.
According to the National Heart, Lung, and Blood Institute, about 600,000 people in the U.S. are affected by venous thromboembolism (VTE) each year. VTE includes both DVT and pulmonary embolism (PE), a serious condition where a clot travels to the lungs.
Certain types of cancer, including pancreatic, stomach, brain, lung, and ovarian cancers, carry the highest risk of blood clots. Treatments like chemotherapy, hormone therapy, and surgery also contribute. These therapies can damage the inner lining of the veins, slow blood flow, or change the composition of the blood in ways that make clots more likely.
Many of these factors fall under what doctors call the Virchow triad—a set of three conditions that increase clotting risk:
If someone already has varicose veins or venous insufficiency, these conditions may increase clotting risk during cancer care.
If you're navigating cancer treatment and have a history of varicose veins or venous insufficiency, your risk of blood clots may be higher than you think. Don’t leave your vein health to chance. At Center for Vein Restoration, our board-certified vein specialists are trained to identify clotting risks early and provide personalized care that supports your overall treatment journey.
Trust the nation’s leading vein center to keep your circulation—and your peace of mind—in check. Schedule your consultation online today or call 240-965-3915.
A study published in the Journal of Thrombosis and Haemostasis found that cancer patients with varicose veins were more likely to develop DVT than those without. Researchers concluded that varicose veins can independently raise the risk of blood clots in people with cancer.
This doesn’t mean that every person with vein disease and cancer will develop a clot, but it does mean that vascular health needs to be part of the discussion when managing cancer treatment.
If you’re currently undergoing cancer treatment, you may wonder whether it’s safe or necessary to treat your varicose veins.
The answer depends on your individual health, type of cancer, and where you are in your treatment journey. In some cases, minimally invasive procedures to treat varicose veins may be recommended before cancer therapy begins or after the most intensive phase of treatment ends.
In other cases, conservative approaches like compression therapy and activity modification may be more appropriate in the short term.
At Center for Vein Restoration, our vein specialists work closely with patients and their broader care teams to tailor treatment plans supporting cancer care and long-term vascular health.
It’s important to watch for warning signs that may indicate worsening vein disease or the development of a blood clot. These include:
If you notice these symptoms, don’t wait. Call a healthcare provider, 911, or go to the emergency room—especially if you have a history of cancer or varicose veins.
Trust the Vein Experts at Center for Vein Restoration
Your veins are essential to your overall health and deserve expert care, especially during or after cancer treatment.
Center for Vein Restoration (CVR) specializes in diagnosing and treating vein disease, including varicose veins, chronic venous insufficiency, and deep vein thrombosis. Our board-certified vein doctors provide advanced, minimally invasive treatments in a comfortable, outpatient setting, with the compassion and expertise you deserve.
If you're managing a cancer diagnosis and have concerns about your vein health, you’re not alone. We’re here to help you stay informed and safe and feel your best.
Call 240-965-3915 to speak with a Patient Services Representative, or schedule your consultation online at a CVR location near you.
1. Can varicose veins cause cancer?
No, varicose veins and their underlying cause—chronic venous insufficiency—do not cause cancer and are not caused by cancer. They are entirely separate conditions with different origins and mechanisms.
2. Why are cancer patients at higher risk for blood clots, especially if they have varicose veins?
Cancer and its treatments can damage blood vessels, slow blood flow, and increase clotting factors in the blood. If someone also has varicose veins, which already impair circulation, the combined risk of deep vein thrombosis (DVT) becomes even greater.
3. Should I treat my varicose veins if I’ve been diagnosed with cancer?
It depends on your overall health, type of cancer, and where you are in your treatment. A vein specialist can help determine whether treating your varicose veins during or after cancer care is safe and beneficial.
4. What are the warning signs of a blood clot I should watch for during cancer treatment?
Symptoms include sudden leg swelling, pain or tenderness (especially in the calf), redness or warmth in the leg, and shortness of breath (which could signal a pulmonary embolism). Seek medical attention immediately if you notice any of these signs.
5. Can a vein specialist help me manage vein problems during cancer care?
Yes. A board-certified vein doctor, like those at Center for Vein Restoration, can assess your risk, provide personalized treatment options, and collaborate with your oncology team to support your vascular health safely and effectively.