Prognostic parameters affecting the effectiveness of removing benign epithelial neoplasms of the LST type in the colon and rectum

Background. It is an undeniable fact that colon polyps are associated with colorectal cancer. The main measure for preventing colorectal cancer is the removal of epithelial neoplasms. However, the effectiveness of resection depends on various factors.

Aim. To determine whether the size, location, macroscopic type, morphology, and the method of resection influence the effectiveness of removal of laterally spreading tumors in the colon and rectum.

Methods. We conducted a retrospective analysis of cases of removal of LST type epithelial neoplasms in the colon and rectum in 2023. Endoscopic resection was performed in 165 patients with benign epithelial neoplasms ranging in size from 11 to 30 mm, with an average size of 15 ± 4.43 mm. Eight patients with giant epithelial neoplasms measuring 6–14 cm in length, up to 2/3 of the circumference of the rectal lumen, underwent SILS-transanal resection. Patients were invited for follow-up examination at 3, 6 and 12 months after removal.

Results. We found a relationship between the relapse of the LST type epithelial neoplasm and the size (from 20 to 30 mm, p = 0.010), macroscopic type (granular mixed-nodular, p = 0.012) and morphology (tubulovillous adenoma, p = 0.028) of the previously resected lesion. In all cases, when removing the epithelial lesion, the edges of the wound on the mucosa were carefully examined for residual tissue. If found, the residual tissue was removed completely. We suggest that tubulovillous adenoma cells might have been implanted into the submucosa with an injector or a snare during removal of the lesion. The SILS-TAR group showed no relapses. However, the SILS-port (COVIDIEN) was recently discontinued.

Conclusion. The possibility of accidental implantation of benign adenoma cells into the submucosa with an injector or a snare during resection warrants further study. It is also necessary to continue the search for and development of new affordable and effective methods for removing giant villous adenomas of the rectum.

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