Can a Tumor Biopsy or Surgery Cause Cancer to Spread?

Medically reviewed by Thanh U. Barbie, MD

There’s little reason to worry that a biopsy or other surgical procedure will allow cancer cells to escape and spread within the body, specialists say.

“A common patient concern is that biopsies may cause microscopic cells from cancers to metastasize to other parts of the body,” says Thanh Barbie, MD, a breast surgeon in the Susan F. Smith Center for Women’s Cancers at Dana-Farber. “However, medical evidence supports that this is unlikely, as most cancer cells that get displaced into the surrounding environment will likely be cleared by the surrounding immune cells.”

In fact, a study of more than 2,000 patients carried out by Mayo Clinic scientists dispelled the myth that cancer biopsies cause disease to spread. The researchers showed that patients who have biopsy procedures to confirm their diagnosis and determine the cancer’s stage had a better outcome and longer survival than patients who did not have a biopsy.

“Biopsies are incredibly valuable for the patient, as having a definitive cancer diagnosis is important in determining and planning the correct treatment for the patient,” adds Barbie. “And if benign disease is found, a patient may be spared from an unneeded surgery. The potential gain from biopsies outweighs the risks, which are commonly limited to discomfort at the biopsy site and bleeding.”

The National Cancer Institute has also addressed this concern in a statement on Common Cancer Myths and Misconceptions:

“The chance that surgery will cause cancer to spread to other parts of the body is extremely low. Following standard procedures, surgeons use special methods and take many steps to prevent cancer cells from spreading during biopsies or surgery to remove tumors. For example, if they must remove tissue from more than one area of the body, they use different surgical tools for each area.”