Are rectal nodules responsible for all digestive complaints?

We have previously suggested that digestive complaints reported by women presenting with deep fibrotic endometriosis of the rectum can be explained by 3 major consequences of disease development: anterior or lateral fixation of the rectum to adjacent anatomic structures, rectal stenosis, and cyclic inflammation of the rectal wall.

Rectal fixation on uterosacral ligaments, uterine cervix, or vaginal fornix may be responsible for abnormal irreducible angulations of the digestive tract ( Figure 1 ), disturbing stool progression, and likely to result in defecation pain or constipation. Rectal stenosis is the consequence of nodule protrusion into the rectum ( Figure 2 ) and may be revealed as an intraluminal indentation on barium enema or computed tomography–based virtual colonoscopy (CTC; Figure 3 ). In low and midrectal nodules located up to 8-10 cm from the anus, stenosis may be clinically confirmed through examination by an intrarectal finger, whereas for nodules located above this limit, CTC examination provides more complete information.

Colorectal endometriosis responsible for abnormal irreducible angulations of the digestive tract

Roman. Bowel dysfunction, endometriosis, and surgery. Am J Obstet Gynecol 2013 .

Deep endometriosis infiltrating rectum and pushing internal rectal layers inside rectal lumen

Deep endometriosis infiltrating the rectum and pushing internal rectal layers inside the rectal lumen. A, Macroscopic view. B, Microscopic view.

Roman. Bowel dysfunction, endometriosis, and surgery. Am J Obstet Gynecol 2013 .

CTC revealing rectal stenosis

Computed tomography-based virtual colonoscopy (CTC) revealing rectal stenosis because of deep endometriosis infiltrating the anterior rectal wall. A, Two-dimensional sagittal view of the insufflated rectum showing an important reduction in rectal diameter. B, Three-dimensional virtual endoluminal view showing narrowing of the lumen corresponding to rectal stenosis. C, Three-dimensional transparent rendering mode double-contrast enema-like view displaying colorectal anatomy and exact location of the stenosis. D, Deep endometriosis nodule responsible for rectal stenosis.

Roman. Bowel dysfunction, endometriosis, and surgery. Am J Obstet Gynecol 2013 .

The thresholds used to define stenosis in imaging examination can vary through different series, and their correlation with clinical symptoms or surgical indications is yet to be established. However, the greater the rectal infiltration, the more frequent the rectal stenosis. A decrease in rectal diameter has been shown from CTC examination in up to 79% of patients whose nodules involved more than 20 mm of the rectum. With regard to clinical impact, women presenting with rectal endometriosis responsible for rectal stenosis had an increased prevalence of constipation, defecation pain, appetite disorders, a longer time necessary to defecate, and an increased stool consistency.

Stenosis responsible for subocclusive symptoms is more likely to occur at the rectosigmoid junction than at the rectal ampulla at which the diameter is naturally larger. Rectal stenosis appears to seldom lead to complete occlusion (1.2% in our series, unpublished data) ( Figure 4 ), which may occur during periods or during the flare-up phase of medical treatment using a gonadotropin-releasing hormone (GnRH) analog.

Magnetic resonance imaging

Magnetic resonance imaging revealing severe rectal stenosis caused by deep endometriosis infiltrating the rectum in a patient presenting with rectal occlusion. A, Sagittal T2-weighted view. B, Axial T2-weighted view.

Roman. Bowel dysfunction, endometriosis, and surgery. Am J Obstet Gynecol 2013 .

The inflammatory nature of endometriosis deposits located in close proximity to the terminal large bowel and local prostaglandin release may explain cyclic alteration of bowel function. Inflammation acts as an irritant factor, leading to an increase in the daily number of bowel movements (usually described as diarrhea and smooth or liquid stools), in defecation pain, and in a feeling of incomplete emptying of the rectum during menstruation.

In a recent study, we compared digestive symptoms in 3 groups of women with distinct localizations of pelvic endometriosis, respectively, superficial endometriosis of the Douglas pouch, deep endometriosis sparing the rectum, and rectal endometriosis. Although women presenting with rectal endometriosis were more likely to present cyclic defecation pain (67.9%), cyclic constipation (54.7%), and a significantly longer stool evacuation time, these complaints were also frequent in the other 2 groups. Because certain digestive complaints also occur in women free of any rectal involvement, the results suggest that, in women affected by rectal endometriosis, these complaints may be unrelated to rectal infiltration by the disease.

The inflammatory mechanism of cyclic digestive function in women with rectal endometriosis has recently been confirmed in a study in which anorectal manometry was performed in women presenting deep endometriotic nodules, which were mainly infiltrating the middle rectum. The most frequent complaints were of dyschesia and constipation (40%), feeling incomplete evacuation (36%), and stool fragmentation (52%). Anorectal manometry performed during the intermenstrual phase revealed the absence of abnormal bowel motility, rectal functional disorders, or nerve plexus dysfunction. The major alteration was an increase in resting pressure for the internal anal sphincter in 80% of women, which was most likely the consequence of chronic inflammation, resulting in pain and muscle spasm, similar to that observed in other inflammatory diseases.

The findings suggest that cyclic inflammation is a critical factor in digestive complaints and offer an explanation for the cyclic character of symptoms. Furthermore, they offer an explanation as to why colorectal resection does not systematically result in the relief of preoperative constipation.

For some women, the relationship between pelvic endometriosis and digestive complaints may be even more complex because of the hidden confounding effect of rectal hypersensitivity. Recent data demonstrated that digestive symptoms consistent with irritable bowel syndrome could be identified in 65% of women with minimal or mild endometriosis and in 50% of women with moderate and severe endometriosis, whereas they are absent in asymptomatic women undergoing laparoscopic sterilization. Rectal barostat examination revealed low rectal sensory threshold and low rectal compliance in women affected by endometriosis, suggesting an increase in rectal sensitivity in women with endometriosis, independent of stage of disease.

Women with endometriosis are at increased risk of developing inflammatory bowel diseases such as Crohn’s disease or ulcerative colitis, more than 20 years after the diagnosis of endometriosis, which may jeopardize the hypothetical causal relationship between presence of a rectal nodule and digestive complaints. Women with irritable bowel syndrome may present cyclic variation of pain intensity ; furthermore, in postmenopausal women the use of hormone replacement therapy seems to be associated with a high incidence of irritable bowel syndrome. A significant improvement in scores of bowel symptoms and quality of life was observed following GnRH analog administration, thus demonstrating that worsening of bowel symptoms during menses is mandatorily related to not only pelvic endometriosis but also to irritable bowel syndrome.

In conclusion, rectal nodules are not found to be responsible for all digestive complaints, and therefore, the presence of such complaints in women affected by rectal endometriosis cannot provide the basis of a strong argument in favor of mandatory colorectal resection.

Does rectal nodule removal relieve all digestive complaints?

There is increasing evidence that women treated surgically for rectal endometriosis may continue to experience postoperative digestive complaints. Despite successful surgery free of intra- and postoperative complications and significant improvement in well-being and pelvic pain, several unpleasant digestive symptoms may be incompletely cured by surgery.

In women undergoing colorectal endometriosis, the rate of women reporting diarrhea halved. Conversely, the rate of women presenting constipation only insignificantly decreased, whereas that of those reporting tenesmus postoperatively increased.

In another retrospective study including a series of women exclusively managed by colorectal resection, despite postoperative improvement in quality of life and gynecological and digestive symptoms, postoperative intensity of constipation only slightly decreased, whereas defecation pain and tenesmus were the same or increased in, respectively, 45%, 22%, and 59% of these women. A randomized controlled trial comparing colorectal resection by open and laparoscopic route provided detailed postoperative data showing that this postoperative improvement in digestive complaints does not apply to all patients or all symptoms, and the overall improvement in constipation was less marked than for dyschesia and diarrhea.

We recently reported preliminary results of a detailed evaluation of postoperative digestive symptoms using gastrointestinal standardized questionnaires in 75 patients treated for rectal endometriosis whose postoperative follow-up exceeded 12 months. Colorectal resection was performed in 35% of cases and conservative rectal surgery (shaving or full-thickness disc excision) in 65%.

For the diagnosis of constipation, the Knowles-Eccersley-Scott-Symptom Questionnaire (KESS) was used (range, 0–39, with overall values superior to 10 in patients with constipation), whereas the quality of life was evaluated using the Gastrointestinal Quality of Life Index (GIQLI) self-administered questionnaire (range, 0–144, and overall values inferior to 100 for patients suffering from gastrointestinal diseases). Mean values of the KESS constipation score and GIQLI were, respectively, 11 ± 7 (range, 0–29) and 104 ± 24 (range, 44–140), supporting evidence that rectal surgery does not provide mandatory relief of digestive symptoms, even though poor digestive outcomes are generally outweighed by relief of dyspareunia, pelvic pain, and an improvement in quality of sexual intercourse.

Several authors have suggested that performing a nerve-sparing technique avoids postoperative digestive complications related to rectal denervation. Landi et al reported their experience concerning nerve-sparing colorectal resection of rectal endometriosis, reporting that preservation of hypogastric plexus and splanhnic nerves may avoid unfavorable functional outcomes related to bladder voiding, rectal voiding, and vaginal lubrification. Patients having benefited from a nerve-sparing technique presented postoperative abnormal bowel movement in 20% vs 49% in controls. Although intraoperative identification of nerves appears to decrease unfavorable rectal functional outcomes following colorectal resection, it is likely that it cannot completely prevent rectal denervation and that rectal dysfunction is related to not only rectal denervation but is also multifactorial.