QS130 - Is Luminal Stenosis an Absolute Contraindication to Watch and Wait?

Sunday, June 2, 2024

1:42 PM – 1:45 PM ET, USA

Location: Room 327

Quick Shot Presenter(s)

Chad Becnel, MD, MBA

Research Fellow
Ochsner Clinic Foundation
New Orleans, LA, United States

All relevant financial disclosures have been managed and will be listed below.
This individual has no financial relationships with ineligible companies.

Author(s)

CL

Catherine Lawton, BS

Medical Student
University of Queensland, Ochsner Clinical School
New Orleans, Louisiana, United States

Disclosure information not submitted.
DK

Danielle Kay, MD

Staff Surgeon
Ochsner
New Orleans, LA, United States

Disclosure information not submitted.
William Kethman, MD, FACS, FASCRS

Staff Surgeon
Ochsner Health
New Orleans, Louisiana, United States

Disclosure information not submitted.
W. Forrest Johnston, MD

Ochsner Health
University of Queensland
New Orleans, LA, United States

All relevant financial disclosures have been managed and will be listed below.
This individual has no financial relationships with ineligible companies.
David Vargas, MD

Senior Staff Surgeon and Vice Chair
Ochsner Clinic
New Orleans, Louisiana, United States

Disclosure information not submitted.
Brian R. Kann, MD, FACS, FASCRS

Chairman & Program Director, Deptartment of Colon & Rectal Surgery
Ochsner Medical Center
University of Queensland/Ochsner Clinical School
New Orleans, Louisiana, United States

Disclosure information not submitted.
CW

Charles Whitlow, M.D., F.A.C.S., F.A.S.C.R.S.

Associate Medical Director, Surgery
Ochsner Medical Center
New Orleans, Louisiana, United States

Disclosure information not submitted.

Senior Author(s)

Jennifer L. Paruch, MD MS FASCRS (she/her/hers)

Staff Surgeon
Ochsner Medical Center
Ochsner Medical Center
New Orleans, Louisiana, United States

Disclosure information not submitted.

Purpose/Background: Patients experience a complete clinical response (cCR) in 30-40% of cases with locally advanced rectal cancer treated with total neoadjuvant therapy (TNT). Stenosis following TNT is considered a contraindication to Watch and Wait although the actual rate of occult malignancy is not known. We hypothesized that stenosis is high risk for persistent cancer. The aim of the study was to establish the rate of occult malignancy present in stenosis following TNT.

Methods/Interventions: A retrospective analysis was performed for patients with locally advanced rectal cancer who underwent treatment with TNT at a single institution between 2019 and 2023. Patients with residual stenosis on their post-treatment exam were identified. Patient demographics, tumor characteristics, surgical pathology reports, and treatment details were obtained by chart review. Patients with residual stenosis were stratified into two groups: stenosis alone (SA), and stenosis with additional exam or imaging features of incomplete clinical response (ICR). Descriptive statistics were used.

Results/Outcomes: A total of 660 patients with rectal cancer were treated during the study period, and 281 (42.6%) received TNT. Post-treatment luminal stenosis was identified in 22 (7.8%) TNT patients, with 18 of these patients going on to surgery. Of the 4 patients who did not receive surgery, one was offered palliative therapies due to prohibitive operative risk, one died prior to intervention, one declined surgery, and one was lost to follow-up. Among patients who underwent resection, 9 (50%) had an ICR, and 9 (50%) had SA based on preoperative assessment. In the ICR group, 8 (88.9%) patients had residual cancer in their surgical specimen, and 1 patient had a complete pathologic response (cPR). In the SA group, cancer was found in 5 (55.6%) of surgical specimens, and 4 (44.4%) patients had cPR (Figure 1). Of the 4 SA patients with a traversable stenosis, 2 had a cPR and 2 had residual cancer. The traversable stenosis group had two patients who were asymptomatic, one patient with clustering and thin bowel movements, and one patient who was diverted at the time of assessment. Type of TNT (long course vs. short course), time from last radiation dose, clinical stage, and height from the anal verge were not significantly associated with cPR (p=0.684, 0.920, 0.571, 0.938, and 0.798 respectively).

Conclusion/Discussion: Patients with residual stenosis after TNT for locally advanced rectal cancer have a high rate of tumor in their surgical specimens. This was found even when the stenosis was endoscopically traversable or there were no other endoscopic or imaging findings of residual tumor. This suggests stenosis is a marker for persistent cancer following total neoadjuvant therapy and supports using residual stenosis as a contraindication to Watch and Wait in patients who are surgical candidates.