Polypoid endometriosis simulating an advanced ovarian neoplasm with infiltration of the intestinal wall: Echoendoscopic description of the case

A 45-year-old patient with a history of endometriotic disease in whom a transvaginal ultrasound revealed a pseudopapillary cystic formation adjacent to the right adnexal mass. The CA-125 marker was 27.8 U/ml (normal: <35 U/ml). Magnetic resonance imaging (MRI) showed 2 cystic formations of 4 cm with an irregular solid component of 17 mm adjacent to the right ovary with pathological enhancement suggestive of mucinous cystadenocarcinoma (Figs. 1 and 2) and probable sigmoid involvement. To assess the infiltration of the wall, a rectal endoscopic ultrasound was requested, which showed a hypoechoic arboriform lesion of 20 mm × 20 mm vascularised inside a cystic cavity (Figs. 3 and 4), without the sigmoid colon being compromised. The surgical specimen revealed endometriotic foci without signs of degeneration.

Figure 1.

Cross-sectional T2 magnetic resonance image.

Figure 2.

Sagittal section T2 magnetic resonance image.

Figure 3.

Conventional rectal endoscopic ultrasound image. Frequency 6 MHz.

Figure 4.

Rectal endoscopic ultrasound image elastography in which the lesion acquires a purplish hue that could simulate a neoplastic lesion.

The novelty of the case that is presented lies, firstly, in the rarity of the polypoid presentation of endometriosis, with around 65 cases having been described in the literature.^1–3 This manifestation raises the differential diagnosis with a neoplastic lesion as the MRI suggested.¹ Secondly, it is the first case in which its appearance is described by digestive endoscopic ultrasound, and thus the dissemination of its ultrasound characteristics among gastroenterologists dedicated to endoscopic ultrasound is of interest.