In a letter to the editor of the Spanish Journal of Gastroenterology, a research group at the Hospital General Universitario Reina Sofía in Murcia, Spain, described a series of cases of intestinal endometriosis, a condition that occurs when endometrial cells infiltrate the bowel and spread in the vicinity of the uterus.

Although often asymptomatic, symptoms that do occur tend to be unspecific and resemble other gastrointestinal conditions, such as irritable bowel syndrome. At times, however, intestinal endometriosis can be characterized by an acute pain in the abdomen.

Because of this, the presence of endometrial cells in the bowel is often detected during surgery conducted for other reasons. The endometrial cells most commonly attach to a part of the colon known as the rectosigmoid colon, but other parts of the intestines can also be affected.

If clinicians suspect intestinal endometriosis, clinical history and physical examination are conducted in combination with imaging techniques. Sometimes clinicians need to expand investigations with explorative laparoscopy, a surgical method of identifying abnormalities in the bowel. A definitive diagnosis, however, cannot be obtained without histological confirmation.

In the case report, “Intestinal endometriosis. Our experience,” the researchers described 17 women diagnosed with the condition between 2006 and 2015. Three of the women, ages 21-53, had previous surgery for endometriosis and were followed on average 24.8 months, although follow-up times varied between one to 60 months.

Two patients were treated only with hormones and radiology, with good response, and another also received non-surgical treatment. In addition, eight patients who underwent surgery were given hormonal therapy.

Surgery as the only treatment was performed in two patients who had deep endometriosis and obstruction of the intestines. Three patients, amounting to 17.6 percent, had a recurrence of endometriosis.

The choice of surgical approaches depends on the site of the endometriosis and is also affected by patients’ wishes to become pregnant. Both open surgery and less invasive techniques are often used, and if patients do not wish to become pregnant, removing the uterus or ovaries might be an option.

Intestinal endometriosis affects between 3 percent and 37 percent of all women diagnosed with endometriosis.