C0203 - Changes in Tumor Micro-Environment With Liquid Nitrogen Spray Cryotherapy and Chemoradiation in Locally Advanced Esophageal Cancer

Tilak Shah, MD, MHS, FACG¹, Jennifer Koblinski, PhD², Rio Boothello, PhD², Chetna Patel, PhD², Hugh Massey, MD³, Bhaumik Patel, MD^3
1McGuire VAMC/VCU, RIchmond, VA; ²Virginia Commonwealth University, Richmond, VA; ³McGuire VAMC/VCU, Richmond, VA

Introduction: In a pilot clinical trial, 44% of patients who underwent a single session of Liquid Nitrogen Spray Cryotherapy (LNSC) prior to neoadjuvant chemoradiation (CRT) had a long-term clinical response (compared to 25% - 30% in published studies of CRT alone). LNSC is hypothesized to enhance immune-mediated cell death of esophageal tumor cells and work synergistically with chemoradiation (CRT), but published studies are lacking. The aim of our study was to assess changes in tumor immune micro-environment (TIME) with LNSC and CRT.


Methods: Matched retrospective case-control study that included locally advanced EC patients who underwent a single session of LNSC plus concurrent chemoradiation (CRYOCHEMOXRT) vs. concurrent chemoradiation alone (CHEMOXRT). Groups were matched for age, histology, and pre-treatment stage. A tissue microarray was generated from the blocks and subjected to multiplex immunofluorescence staining for pancytokeratin (tumor cells), CD3 (overall T cell) and CD8 (Cytotoxic T cells), FOXP3 (regulatory T cells). The images were analyzed with Vectra Polaris Automated Quantitative Pathology Imaging System and data was analyzed using R Studio

Results: Paired pre- and post-treatment tissue was available for 5 patients in the CRYOCHEMOXRT group and 4 patients in the CHEMOXRT group. Intra-tumor total T lymphocytes (IT-TILs) increased at least five-fold pre- and post-treatment in 40% of patients in the CRYOCHEMOXRT group vs. 25% of patients in the CHEMOXRT group. IT-TILs increased at least five-fold pre- and post-treatment in 60% of patients in the CRYOCHEMOXRT vs. 50% in the CHEMOXRT group. However, regulatory T cells also increased more frequently with CRYOCHEMOXRT (40% vs. 25%). In the CRYOCHEMOXRT group, mean survival in patients who had a five-fold increase in IT-TILs vs. patients with less than five-fold response was 1402 days vs. 686 days (Table 1).

Discussion: In this exploratory study, LNSC increased likelihood of IT-TILs with CRT. Patients with a robust cytotoxic T cell response had a longer survival than patients who did not have a significant immune response. Larger studies are needed to corroborate these findings, and to better characterize tumor immune response with LNSC and CRT.



Disclosures:


Tilak Shah, MD, MHS, FACG¹, Jennifer Koblinski, PhD², Rio Boothello, PhD², Chetna Patel, PhD², Hugh Massey, MD³, Bhaumik Patel, MD³. C0203 - Changes in Tumor Micro-Environment With Liquid Nitrogen Spray Cryotherapy and Chemoradiation in Locally Advanced Esophageal Cancer, ACG 2022 Annual Scientific Meeting Abstracts. Charlotte, NC: American College of Gastroenterology.