Kasim L Mirza, MD1, Andreas M Kaiser, MD, FACS, FASCRS2. 1Keck USC Dept of Surgery, 2Keck USC Dept of Surgery, Division of Colorectal Surgery
Introduction: Transanal local excision is an excellent treatment choice for benign rectal lesions. For rectal cancer, however, local full-thickness excisions are fraught with high local recurrence rates – even if limited to early and best selected lesions. This corroborated observation is likely caused by a combination of missed nodal disease and direct implantation of tumor cells into the mesorectum, which upstages even early T1 lesions to at least a T3 lesion. The treatment of choice for invasive adenocarcinoma consists of an oncological total mesorectal resection, possibly with other modalities. Rectal tumors of uncertain behavior can present a treatment dilemma between over-treatment vs under-treatment.
Concept: If the nature of a lesion is not certain or if contradictory results have been obtained, we propose a superficial local excision as a mucosal excisional biopsy to establish the diagnosis while avoiding interference with subsequent definitive treatment modalities by preserving the integrity of the external rectal wall and mesorectum. A benign final pathology concludes the treatment, whereas a detection of invasive cancer will be managed with a subsequent oncological resection.
Methods: This is a case report of a 70-year-old woman found to have a 4.4cm villous lesion in the mid to distal rectum without proven or disproven invasive cancer. A TEMS-guided mucosal resection of the rectal mass at 3 cm above the anal verge was performed whereby the lesion was dissected off the underlying muscularis.
Results: With preoperative discrepant ERUS and MRI staging uT0-1 vs cT3 lesion, a technically successful mucosal resection of the large rectal mass was carried out. Pathology revealed a tubulovillous adenoma without high grade dysplasia or malignancy and a complete resection.
Conclusion: TEMS mucosal excisional biopsy of rectal tumors of uncertain behavior allows for a less invasive diagnostic approach that may (a) be definitive treatment if the lesion is proven benign, or (b) confirm the need for more aggressive treatment without having burned any treatment bridges or upstaged an early tumor by violating the mesorectal plane. An oncologic resection with appropriate (neo-)adjuvant chemotherapy can be carried out while preventing the potential for tumor seeding at initial operation.
Presented at the SAGES 2017 Annual Meeting in Houston, TX.
Abstract ID: 88479
Program Number: P201
Presentation Session: iPoster Session (Non CME)
Presentation Type: Poster