Abstract 1649: Extent and location of tumor infiltrating lymphocytes in colon cancer predicts outcome to adjuvant active specific immunotherapy

• Published in: Cancer research (Chicago, Ill.) Vol. 74; no. 19_Supplement; p. 1649
• Main Authors: Hooijberg, Erik, Turksma, Annelies W., Shamier, Marc, Lam, Kevin, Coupe, Veerle MH, Weger, Vincent A. de, Belien, Jeroen AM, Eertwegh, Alfons J. van den, Meijer, Gerrit A., Meijer, Chris JLM
• Format: Journal Article
• Language: English
• Published: 01.10.2014
• ISSN: 0008-5472; 1538-7445
• DOI: 10.1158/1538-7445.AM2014-1649

Abstract Purpose: We investigated the prognostic and predictive value of tumor infiltrating lymphocytes (TIL) in colorectal cancer in a cohort of patients who previously took part in a trial on adjuvant Active Specific Immunotherapy (ASI). Experimental Design: We determined the numbers of CD3+ and CD8+ cells in archival tumor samples of 110 colorectal cancer patients as total infiltrating TIL, intraepithelial TIL and stromal TIL. Survival curves were used to determine the prognostic and predictive value of TIL. Results: Patients with microsatellite instable (MSI) tumors had higher numbers of intraepithelial CD3+ and CD8+ TIL compared to patients with microsatellite stable (MSS) tumors. Patients with MSI tumors had a good prognosis. Patients with MSS cancers with high intraepithelial or stromal TIL numbers had a better prognosis compared to those with low TIL numbers. Significant survival benefits were found for the disease specific survival (DSS) and recurrence free interval (RFI) for patients with high infiltrates of stromal CD3+ or intraepithelial CD8+ cells. Additionally high numbers of total CD8+ and high stromal CD8+ cells gave a significant difference in RFI compared to low TIL numbers. The numbers of TIL found in MSS tumors also have predictive value with respect to response to adjuvant ASI treatment. Compared to controls significance was reached in ASI treated patients with high total CD3, high stromal CD3 or high stromal CD8 numbers in DSS as well as RFI. Conclusion: ASI therapy is effective in patients with MSS colorectal tumors harboring high numbers of preexisting stromal CD3 or CD8 positive TIL. Citation Format: Erik Hooijberg, Annelies W. Turksma, Marc Shamier, Kevin Lam, Veerle MH Coupe, Vincent A. de Weger, Jeroen AM Belien, Alfons J. van den Eertwegh, Gerrit A. Meijer, Chris JLM Meijer. Extent and location of tumor infiltrating lymphocytes in colon cancer predicts outcome to adjuvant active specific immunotherapy. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 1649. doi:10.1158/1538-7445.AM2014-1649