Cancer and Blood Clot Risk: What You Need to Know

If you or a loved one has cancer, you’ve probably heard about chemotherapy, radiation, and surgery. One hidden danger many overlook is the higher chance of blood clots. Those clots can cause serious problems like deep‑vein thrombosis (DVT) or even a pulmonary embolism. Knowing why this happens and what you can do about it can save lives.

Why Cancer Increases Clotting

Cancer cells release chemicals that make your blood thicker. Tumors also press on nearby veins, slowing blood flow. On top of that, treatments such as chemo and hormonal therapy can irritate blood vessels. All these factors combine to turn a normally smooth‑running system into a sticky one, raising clot risk dramatically.

Age and other health conditions matter, too. Older patients, those with heart disease, or people who are less mobile after surgery are especially vulnerable. Even a short period of bed rest can let blood pool in the legs, giving clots a chance to form.

Practical Steps to Lower Your Risk

First, stay moving. Simple leg lifts, ankle pumps, or short walks (as your doctor allows) keep blood flowing. If you’re on a long hospital stay, ask about compression stockings; they gently squeeze the legs and help prevent pooling.

Second, watch your hydration. Dehydration thickens blood, so aim for at least eight glasses of water a day unless your doctor says otherwise. A balanced diet with enough vitamin K can also support healthy clotting, but talk to your doctor before taking supplements.

Third, discuss medication options. Some cancer patients benefit from low‑dose blood thinners (anticoagulants) during high‑risk periods. Your oncologist can weigh the benefits against bleeding risks and prescribe the right dose.

Fourth, know the warning signs. Look for swelling, pain, or redness in one leg, sudden shortness of breath, or chest pain that worsens when you breathe deeply. If any of these pop up, seek medical help right away—early treatment can prevent serious complications.

Finally, keep regular follow‑up appointments. Your care team will monitor blood tests, adjust meds, and catch problems before they get out of hand. Don’t skip those check‑ins, even if you feel fine.

Living with cancer is tough, but taking a few practical steps can dramatically cut your clot risk. Stay active, stay hydrated, know the signs, and keep the conversation open with your doctors. Small changes add up to big protection.