Women with Deep Infiltrating Endometriosis Have a Higher Risk of Appendix Involvement

Endometriosis of the appendix is a known cause of infertility

Key Points

Highlights:

• Women with deep infiltrating endometriosis have a higher risk of developing endometriosis of the appendix compared to women with superficial endometriosis or those without.

Importance:

• Endometriosis of the appendix is a rare condition but a known cause of infertility. The risks and benefits associated with an elective coincidental appendectomy should be considered.
• There is no consensus about which patients have a higher risk of appendiceal involvement and might benefit from the appendectomy.

What’s done here?

• Researchers analyzed 395 women who underwent benign gynecological surgery between July 2009 and February 2014 at a tertiary referral center in the U.S.
• They compared the rate of endometriosis of the appendix in women who were diagnosed with deep infiltrating endometriosis (DIE), superficial endometriosis, or no endometriosis. 

Key results:

• Women with deep infiltrating endometriosis have a 5.9 times higher risk of developing appendiceal endometriosis compared to women without endometriosis 
• Women with deep infiltrating endometriosis have 2.7 times increased risk of developing appendiceal endometriosis compared to women with superficial endometriosis.
• Overall, endometriosis was identified in 151 (38.2%) women during surgery, of whom 82 (54.3%) had DIE. All women with an ovarian endometrioma had concurrent DIE.
• Women with DIE were older than those with superficial endometriosis.
• Women with DIE or with superficial endometriosis had a lower BMI than those without the disease. More women with DIE and superficial endometriosis were nulliparous and had chronic pelvic

  pain as compared with women without the disease.

Limitations of the study:

• The study has been conducted using data obtained from a single site, which may influence the findings.
• Not all women undergoing gynecologic surgery desired appendectomy; thus, the overall prevalence of appendix involvement was not possible.
• It was not possible to prospectively study a cohort of patients to determine whether coincidental appendectomy prevents future surgical intervention for endometriosis or pelvic pain. 

Lay Summary

Women with deep-infiltrating endometriosis, a form of endometriosis that invades the abdominal and pelvic cavity, have an increased risk of developing endometriosis of the appendix. It is therefore important to check women with deep infiltrating endometriosis for appendix involvement during endometriosis surgery in these patients.

Researchers from the University of North Carolina, Chapel Hill, NC, USA, led by Dr. Joanne Garrett, conducted a study to determine whether women with deep infiltrating endometriosis have an increased risk of appendiceal endometriosis compared to those with superficial endometriosis or no endometriosis, published in the International Journal of Gynecology & Obstetrics. 

The team analyzed women who underwent benign gynecological surgery between July 2009 and February 2014. During this period, 395 women were examined, and endometriosis diagnosed in 151 (38.2%) of them, and 82 had deep infiltrating endometriosis.The presence of endometriosis confirmed by histopathologic evaluation and was considered deeply infiltrating if it penetrated more than 5 mm. 

A total 52 women had endometriosis of the appendix (13.2 percent of all 395 women). When they analyzed subgroups of women depending on the type of endometriosis that they had, the researchers found that 39 percent of women with deep infiltrating endometriosis also had endometriosis of the appendix, while only 11.6 percent of women with superficial endometriosis had endometriosis of the appendix as well. 

Using statistical analysis, the researchers calculated that women with deep infiltrating endometriosis had a 5.9 times higher risk of developing endometriosis of the appendix compared to women without endometriosis, and 2.7 times higher risk compared to those with superficial endometriosis.

Endometriosis of the appendix is a very rare condition thought to affect less than one percent of all women with endometriosis. However, when it happens it can cause infertility. The condition is difficult to diagnose since the symptoms are very similar to those of acute appendicitis. It can be treated with surgery.

Research Source: https://www.ncbi.nlm.nih.gov/pubmed/28755505