Extended Full-thickness Transanal Local Excision to Treat Ultra-low Rectal Cancer: an Initial Clinical Exploration

Objective: To investigate the feasibility of extended full-thickness transanal local excision for rectal cancersinvading anorectal junction.
Methods: Four patients with small (size ≤3cm) unfixed rectal cancer, which extendedinto the upper anal canal, were submitted to transanal local excision with a dissection plane extended to thestriated muscle layer around the upper anal canal, so that a portion of striated muscle beneath or around thetumor was excised en bloc with the anorectal wall. The defect in the anorectal wall was laid open to granulate andepithelize.
Results: The mean operative time was 28±6 min, with no related mortality. Postoperative pathologicalexamination confirmed clear resection and revealed 1 T2, 2 T1, and 1 Tis carcinoma. The median follow-upwas 3.2 months (range, 1.5-13.0 months). Minor soiling with flatus incontinence was common during the firstpostoperative month. Two patients with a follow-up longer than 3 months had perfect anal continence. No localrecurrence was observed.
Conclusion: Extended full-thickness transanal local excision for rectal tumors lyingat the anorectal junction is safe and simple. Patients with partial excision of striated muscle around the upperanal canal may still enjoy good anal continence. Further studies on extended full-thickness transanal excisionare worthwhile.