A study of more than 2000 patients refutes the idea that biopsies cause cancer to spread.
In a study published in Gut, researchers showed that patients who received a biopsy had better overall survival and similar cancer-free survival rates as patients who did not have a biopsy.
The team studied pancreatic cancer but said their findings likely apply to other cancers because the diagnostic technique used in this study—fine needle aspiration—is commonly used across tumor types.
“This study shows that physicians and patients should feel reassured that a biopsy is very safe,” said study author Michael Wallace, MD, of the Mayo Clinic in Jacksonville, Florida.
“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.”
This is the second study Dr Wallace and his team have conducted to examine the risk of biopsy.
In a 2013 study published in Endoscopy, the researchers examined outcomes in 256 pancreatic cancer patients treated at the Mayo Clinic in Jacksonville. The team found no difference in cancer recurrence between 208 patients who had ultrasound-guided fine needle aspiration (EUS-FNA) and the 48 patients who did not have a biopsy.
In the current study, the researchers examined 11 years (1998-2009) of Medicare data on patients with non-metastatic pancreatic cancer who underwent surgery. The team examined overall survival and pancreatic cancer-specific survival in 498 patients who had EUS-FNA and in 1536 patients who did not have a biopsy.
During a mean follow-up time of 21 months, 285 patients (57%) in the EUS-FNA group and 1167 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.
The median overall survival in the EUS-FNA group was 22 months, compared to 15 months in the non-EUS-FNA group. Multivariate analysis showed that receipt of EUS-FNA had a borderline significant association with improved overall survival (hazard ratio=0.84, P=0.03).
The median cancer-specific survival was 24 months in the EUS-FNA group and 18 months in the non-EUS-FNA group. Multivariate analysis revealed no significant difference between the two groups (hazard ratio=0.87, P=0.12).
“[Biopsies provide] very valuable information that allow us to tailor treatment,” Dr Wallace noted. “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.”
