By Robert Preidt
SATURDAY, May 30, 2015 (HealthDay News) -- Thousands of breast cancer patients in the United States might be spared a second surgery if more tissue was removed during initial breast-conserving, partial mastectomy surgery, a new study suggests.
Partial mastectomy, often called lumpectomy, aims to conserve breast tissue and stops short of a full mastectomy.
More than half of the nearly 300,000 women in the United States diagnosed with breast cancer each year undergo this type of surgery, according to researchers from the Yale Cancer Center in New Haven, Conn. However, after the procedure, 20 percent to 40 percent of these patients still have cancer cells at the edges of the areas where tissue was removed. That often means a second surgery, to ensure that no cancer remains.
The new study was led by Dr. Anees Chagpar, an associate professor of surgery at Yale School of Medicine, and included 235 patients with stage 0 to III breast cancer who underwent partial mastectomy in the normal way.
All of the women were then randomly selected in the operating room to have additional tissue removed or not.
Removing the extra tissue reduced by half the chances of requiring a second surgery, the researchers found.
"Despite their best efforts, surgeons could not predict where the cancer was close to the edge," Chagpar noted in a Yale news release.
Removal of so-called "cavity shave margins" reduced the rate at which cancer cells remained in the tissue margin in half, "without compromising cosmetic outcome or increasing complication rates," according to Chagpar, who also directs The Breast Center at Smilow Cancer Hospital at Yale-New Haven.
Her team said it will track outcomes for the patients for five years to assess how the removal of extra tissue affects the risk of a cancer recurrence.
"This randomized controlled trial has the potential to have a huge impact for breast cancer patients," Chagpar said. "No one likes going back to the operating room, especially not the patients who face the emotional burden of another surgery."
However, two experts not involved with the study cautioned that there are good reasons to be conservative when it comes to tissue excision in the operating room.
"Randomly removing additional breast tissue is not necessarily in the best interest of the individual patient and may lead to negative cosmetic outcomes over time," said Dr. Susan Boolbol, chief of the division of breast surgery at Mount Sinai Beth Israel in New York City.
"When exploring ways to decrease the re-excision rate, we must be mindful of the fact that removing healthy, non-cancerous tissue does not help any patient and can potentially have a negative impact on their cosmetic outcome in the long term," she added.
Dr. Stephanie Bernik is chief of surgical oncology at Lenox Hill Hospital, also in New York City. She acknowledged that "needing to go back for additional surgery to obtain clear margins after breast cancer surgery is an age-old problem."
However, "more tissue removal can lead to a worse cosmetic result, even though this study did not find that to be true," she added.
Emerging technologies may lead to more precise surgeries in the future, Bernik said. "Devices to evaluate margins 'intra-operatively' are now being brought into use as well," she said. "All of these findings will ultimately help reduce the number of times a patient may have to return to the operating room."
The study was published online May 30 in the New England Journal of Medicine and is also slated for presentation on Saturday at the annual meeting of the American Society of Clinical Oncology, in Chicago.