US Quiz of the Month – March 2015


A 38 year-old female patient, with no relevant previous medical history, was referred to our unit for evaluation of recurrent left iliac fossa pain, without associated symptoms. No blood test abnormalities were found. Physical examination, pelvic and abdomen ultrasound were normal. Colonoscopy was then performed identifying, at 15 cm from the anal verge, a 3cm bulge in the lumen covered by normal mucosa. These findings were suggestive of a subepithelial lesion (Figure 1).

Figure 1. Colonoscopy: 3cm subepithelial lesion, at 15 cm from the anal verge.


Endoscopic ultrasonography (EUS) showed a 30mm hypoechoic heterogeneous mass, with no precise limits and with all layers involved (Figure 2).

Figure 2. EUS: 30mm hypoechoic heterogeneous mass, with no precise limits and with all layers involved.


FNA (22G needle) of the lesion was performed and cytologic examination revealed the combination of endometrial glands and stroma. These findings were compatible with endometriosis.

Pelvic MRI (Figure 3) and endovaginal ultrasound found no other endometriotic lesions in the pelvis. According to patient preference, hormonal therapy was started and symptoms remission was achieved.


Figure 3. Pelvic MRI: coronal (left) and transverse (right) planes. Rectosigmoid endometriosis, with no other endometriotic lesions in the pelvis.



Subepithelial lesions of the gastrointestinal tract are commonly incidentally discovered during routine upper endoscopy and colonoscopy. In the colon, subepithelial lesions mostly occur in the rectum and cecum, but lipomas (the most frequent colonic subepithelial lesion) may be seen in any part of the colon 1. Lipomas are usually yellowish, soft and deformable subepithelial lesions and colonoscopic inspection with demonstration of the pillow sign is enough for a definitive diagnosis.  EUS is the goldstandard for evaluation of other distal colonic subepithelial lesions. In EUS series, the most frequent colonic subepithelial lesions are GISTs, carcinoid tumors and rectosigmoid endometriosis 1.

Bowel endometriosis affects between 3.8% and 37% of women with endometriosis and is referred to the infiltration of the intestinal wall by endometrial-like gland and stroma reaching at least the subserous fat tissue and the subserous part of the enteric plexus. It is associated with the presence of other endometriotic lesions in the pelvis in over 99% of patients. Nodules infiltrating the intestinal muscular layer cause a wide range of symptoms that may mimic an irritable bowel syndrome. Rectal EUS has been used for bowel endometriosis evaluation as it permits to estimate the depth of infiltration in the intestinal wall (namely muscularis propria infiltration), the maximum diameter of the lesions (usually hypoechoic lesions, with no precise limits) and the distance of the lesions from the anus 2. EUS has shown high sensitivity and specificity in the diagnosis of endometriosis of the rectovaginal septum and of the rectal wall 2. Hormonal or surgical therapy may be considered depending on nodules size, severity of symptoms and desire of the patient to conceive 3.



1. Menon L, Buscaglia J. Endoscopic approach to subepithelial lesions, Therap Adv Gastroenterol. 2014; 7(3): 123–30.

2. Ferrero S, Camerinin G, Maggiore U, et al. Bowel endometriosis: Recent insight and unsolved problems, World J of Gastrointestinal Surgery. 2011; 3(3): 31–38.

3. Remorgida V, Ferrero S, Fulcheri E, et al. Bowel endometriosis: presentation, diagnosis and treatment. Obstet Gynecol Surv 2007; 62(7):461-70.



José Pedro Rodrigues1, Susana Marques1, Maria Ana Túlio1, Pedro Barreiro1, Pedro Pinto Marques2, Cristina Chagas1.

1. Gastroenterology Department, Centro Hospitalar de Lisboa Ocidental, Lisbon, Portugal

2- Gastroenterology Department, Garcia de Orta Hospital, Lisbon, Portugal