Genetic analysis of benign deep-infiltrating endometriosis lesions revealed the presence of genetic mutations in genes commonly associated with cancer, according to a study published in the New England Journal of Medicine. This finding may help develop new diagnostic tools to distinguish between aggressive and non-aggressive endometriosis.

“Our discovery of these mutations is a first step in developing a genetics-based system for classifying endometriosis so that clinicians can sort out which forms of the disorder may need more aggressive treatment and which may not,” Ie-Ming Shih, MD, PhD, senior author of the study, said in a press release. Shih is a professor of gynecologic pathology at Johns Hopkins University School of Medicine, Baltimore, Maryland.

In the study “Cancer-Associated Mutations in Endometriosis without Cancer” researchers conducted a genetic screen to evaluate the presence of genetic mutations in endometriosis tissue samples that could not be found in healthy endometrium tissue. Analysis of tissue samples collected from 24 women revealed that 79% of them had one or more mutations that were present only in their endometriosis tissue, but not in their normal endometrium tissue.

Five of the patients presented mutations in genes commonly associated with cancer, which included ARID1A, PIK3CA, KRAS and PPP2R1A. All these genes have important roles in controlling cell growth, cell invasion, and DNA damage repair, and have been associated with an aggressive form of ovarian cancer. These findings suggest that although endometriosis may start within normal cells, acquired mutations may change their fate.

“We were surprised to find cancer-linked genes in these benign endometriosis samples because these lesions do not typically become cancer,” said Nickolas Papadopoulos, PhD, professor of oncology and pathology at the Johns Hopkins Kimmel Cancer Center.

“We don’t yet understand why these mutations occur in these tissues, but one possibility is that they could be giving the cells an advantage for growth and spread,” he added.

The results of this study may contribute to a better understanding of endometriosis and pave the way for development of new molecular diagnostic tests and therapies to improve patients’ care. However, more studies are needed to fully understand the real impact these genetic variations may have in both disease aggressiveness and patient’s outcome, the authors added.