Biopsies Do Not Promote Cancer Spread

Endoscopic ultrasound-guided fine needle aspiration (EUS-FNA) does not cause pancreatic cancer to extend, according to a new study.

Researchers at the Mayo Clinic (Jacksonville, FL, USA) conducted a study involving 2,034 patients with locoregional pancreatic cancer who underwent curative intent surgery from 1998 to 2009; of these, 498 (24%) patients received EUS-FNA within the peri-diagnostic period (EUS-FNA group). The other 1,536 patients who did not receive EUS evaluation, or who underwent EUS without FNA, were included in the non-EUS-FNA group. Overall survival and pancreatic cancer-specific survival were compared after controlling for relevant covariates.

The results showed that during a mean follow-up time of 21 months, 285 patients (57%) in the EUS-FNA group and 1,167 patients (76%) in the non-EUS-FNA group died. Pancreatic cancer was identified as the cause of death for 251 patients (50%) in the EUS-FNA group and 980 patients (64%) in the non-EUS-FNA group. After controlling for age, race, gender, tumor histology, tumor stage, tumor grade, tumor location, radiation, chemotherapy, and other factors, EUS-FNA was marginally associated with improved overall survival, but did not affect cancer-specific survival. The study was published online on January 9, 2015, in Gut.

“Biopsies offer very valuable information that allow us to tailor treatment; in some cases, we can offer chemotherapy and radiation before surgery for a better outcome, and in other cases, we can avoid surgery and other therapy altogether,” said senior author, gastroenterologist Prof. Michael Wallace, MD, MPH. “Physicians and patients should feel reassured that a biopsy is very safe. We do millions of biopsies of cancer a year in the US, but one or two case studies have led to this common myth that biopsies spread cancer.”

During EUS-FNA, a flexible endoscope is inserted into the patient's body through the mouth or the anus. The tip of the endoscope has a small rotating ultrasound system that can peer about 10 cm into surrounding tissue. When the site that needs to be biopsied has been located, a fine needle is inserted down a canal in the endoscope and inserted into the area. Several samples of tissue are then retrieved and examined by a pathologist who is often in the room during the procedure.

Related Links:
Mayo Clinic