MAYO RESEARCHERS FIND CANCER BIOPSIES DO NOT PROMOTE CANCER SPREAD

Mayo Researchers Find Cancer Biopsies Do Not Promote Cancer Spread

JACKSONVILLE, Fla. — A study of more than 2,000 patients by researchers at Mayo Clinic’s campus, has dispelled the myth that cancer biopsies cause cancer to spread. In the Jan. 9 online issue of Gut, they show that patients who received a biopsy had a better outcome and longer survival than patients who did not have a biopsy.

The image shows a pancreas tumor being biopsied with a needle as visualized by endoscopic ultrasound. The endoscope was located within the stomach (passed via the mouth). An ultrasound probe at the tip of the endoscope allows visualization of the pancreas which is located immediately next to the stomach. A long needle is guided through the endoscope and into the tumor under ultrasound guidance.

The researchers studied pancreatic cancer, but the findings likely apply to other cancers because diagnostic technique used in this study — fine needle aspiration — is commonly used across tumor types, says the study’s senior investigator and gastroenterologist Michael Wallace, M.D.

Fine needle aspiration is a minimally invasive technique that uses a thin and hollow needle to extract a few cells from a tumor mass. A long-held belief by a number of patients and even some physicians has been that a biopsy can cause some cancer cells to spread.

While there have been a few case reports that suggest this can happen — but very rarely — there is no need for patients to be concerned about biopsies, says Dr. Wallace.

“This study shows that physicians and patients should feel reassured that a biopsy is very safe,” he says. “We do millions of biopsies of cancer a year in the U.S., but one or two case studies have led to this common myth that biopsies spread cancer.”

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,” Dr. Wallace says.

Surgery for pancreatic cancer is “a very big operation,” and “most people should want to make sure they have cancer before they undergo surgery,” he says. One study has shown that 9 percent of patients who underwent surgery because of suspected pancreatic cancer actually had benign disease.

Dr. Wallace and his team have conducted two separate studies to examine the risk of biopsy.

In a 2013 study published in Endoscopy, the researchers examined outcomes in 256 pancreatic cancer patients treated at Mayo Clinic in Jacksonville, Florida. They 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, they examined 11 years (1998–2009) of Medicare data on patients with non-metastatic pancreatic cancer who underwent surgery. The researchers examined overall survival and pancreatic cancer-specific survival in 498 patients who had EUS-FNA and 1,536 patients who did not have a biopsy.

During a mean follow-up time of 21 months, 285 patients (57 percent) in the EUS-FNA group and 1,167 patients (76 percent) in the non-EUS-FNA group died. Pancreatic cancer was identified as the cause of death for 251 patients (50 percent) in the EUS-FNA group and 980 patients (64 percent) in the non-EUS-FNA group.

Median overall survival in the EUS-FNA group was 22 months compared to 15 months in the non-EUS-FNA group.

“Biopsies are incredibly valuable. They allow us to practice individualized medicine — treatment that is tailored for each person and designed to offer the best outcome possible,” Dr. Wallace says.

Source: Mayo Clinic News Network

A SIMPLE TECHNIQUE MAY BE MOST EFFECTIVE IN PREVENTING HEART DISEASE AFTER RADIATION THERAPY FOR BREAST CANCER

 Women who have breast cancer on their left side present a particular challenge to radiation oncologists. Studies have shown that the risk of heart disease is higher in this group of women after radiation treatment because it can be difficult to ensure that a sufficient dose of radiation is delivered to the left breast while adequately shielding the heart from exposure. New research shows a woman who holds her breath during radiation pulses can greatly reduce radiation exposure to the heart.

"Radiation therapy is commonly prescribed to patients with breast cancer following surgery as a component of first-line therapy," said first author Harriet Eldredge-Hindy, M.D., a Chief Resident and researcher in the Department of Radiation Oncology at Thomas Jefferson University "We wanted to determine how effective breath-hold could be in shielding the heart from extraneous radiation exposure during treatment of the left breast."

Recent studies have shown women with cancer in the left breast are at higher risk of heart disease, and that the risk increases proportionately with the dose of radiation the heart is exposed to during treatment. A number of techniques have been developed to reduce exposure to the heart including prone positioning (lying flat on the belly on a bed that only exposes the left breast), intensity-modulated radiation therapy (IMRT), and accelerated partial breast irradiation. The breath-hold technique allows doctors to monitor a patient's breath for the position that shifts the heart out of the range of the radiation beam.

In the largest prospective study to date, following women for 8 years post treatment, 81 women were asked to hold their breath during radiation treatment for breast cancer- a process that was repeated until therapeutic dose was reached. The researchers found that patients capable of holding their breath over the course of treatment had a 90 percent disease-free survival, and a 96 percent overall survival, with a median reduction in radiation dose to the heart of 62 percent. The findings were published online this week in the journal Practical Radiation Oncology.

"Given that this technique helps to shield the heart during radiation treatment for breast cancer," said Rani Anne, M.D., Associate Professor of Radiation Oncology at Thomas Jefferson University and senior author on the study, "we routinely offer breast cancer treatment with the breath hold technique at Jefferson."

Source: EurekAlert