Diagnosis of an unexpected colonic submucosal lesion by double-clip traction endoscopic submucosal dissection

Endoscopic submucosal dissection (ESD) is a reference method for the management of extensive lesions of the digestive tract. Its development extended the indications of ESD to lesions that were previously difficult to treat such as recurrences, lesions invading a diverticulum or the appendix, and submucosal lesions that may not be treatable by endoscopic mucosal resection [1] [2].

Colonic submucosal lesions are common, and their definitive diagnosis can be problematic. En bloc resection is essential in cases of submucosal tumors because of the potential for such to be carcinoid tumors or gastrointestinal stromal tumors (GISTs), and careful histological analysis is required [3] [4]. The submucosal nature of these lesions makes classic ESD challenging.

We report here the case of a 75-year-old patient in whom a submucosal lesion in the right colon was detected during a screening colonoscopy ([Fig. 1]). The submucosal lesion was < 1 cm in diameter. Previous biopsies yielded ambiguous findings. We hypothesized that the patient had a GIST or carcinoid tumor, and so we performed resection by ESD to facilitate diagnosis and, potentially, be curative.

Fig. 1 Submucosal lesion in the right colon.

After injection and circumferential incision, traction using the double-clip traction method [5] was performed to ensure complete resection ([Fig. 2]). This method showed a small submucosal space immediately beneath a hard, whitish submucosal lesion ([Video 1]). The patient was discharged the day after the resection and did not develop any complications. Histopathological analysis revealed an unexpected diagnosis of a submucosal nematode with an inflammatory reaction as a gigantocellular epithelioid granuloma with free lateral and deep margins ([Fig. 3], [Fig. 4]).

Fig. 2 Circumferential submucosal dissection.

Video 1 Diagnosis of an unexpected colonic submucosal lesion by double-clip traction endoscopic submucosal dissection.

Fig. 3 Submucosal nematode.

Fig. 4 Submucosal nematode (zoom).

This case demonstrates the complexity of management and the difficulty of histological prediction of colonic submucosal tumors, which range from digestive parasitosis to carcinoid tumor. ESD is a less invasive and efficient method of diagnosing and potentially treating patients with colonic submucosal tumors.

Endoscopy_UCTN_Code_CCL_1AD_2AJ

Competing Interest

The authors declare that they have no conflict of interest.

• References

• 1 Lambin T, Yzet C, Albouys J. et al. Endoscopic submucosal dissection of a subepithelial neuroendocrine tumor located in the duodenum using a countertraction technique. Endoscopy 2021;
• 2 Albouys J, Geyl S, Guyot A. et al. Endoscopic submucosal dissection with double-clip traction for recurrent adenoma. Endoscopy 2020; 52: E439-E440
• 3 Liu Z, Sun Y, Li Y. et al. Colonic gastrointestinal stromal tumor: a population-based analysis of incidence and survival. Gastroenterol Res Pract 2019; 2019: 3849850
• 4 Kukar M, Kapil A, Papenfuss W. et al. Gastrointestinal stromal tumors (GISTs) at uncommon locations: a large population based analysis. J Surg Oncol 2015; 111: 696-701
• 5 Bordillon P, Pioche M, Wallenhorst T. et al. Double-clip traction for colonic endoscopic submucosal dissection: a multicenter study of 599 consecutive cases (with video). Gastrointest Endosc 2021; 94: 333-343

Publication History

Article published online:
21 November 2022