Abstract 4519: Preliminary data of a stool test for lung cancer from a prospective study

Abstract Lung cancer is the biggest cancer killer Worldwide with a limited prognosis despite personalized treatment regimens. Low-dose CT scanning as a means to early diagnosis has been disappointing due to the high false positive rate. Other non-invasive means of testing need to be developed that offer both timely diagnosis and predict prognosis. Methods: In the course of stool testing in a large scale testing of patients at increased risk of CRC we were able to ascertain 55 patients documented to have prospectively been diagnosed with lung cancer. Stool and colonic effluents were tested for anti-adenoma antibody (Adnab-9) reactivity by ELISA and Western blot. Survival data were obtained where available. Results: Of 55 cancers 40% were squamous (SSC), 23.7 were adenocarcinoma, 14.6 small, 12.7 large cell and 9% were designated NSCLC. 49.1% of the lung cancer patients had adnab-9 testing. Overall 53.6% (14 of 26) had positive testing compared to 2 of 11 controls (18.2%) which bordered on significance (OR5(CI1-29)). Cancers with higher lethality were more likely to test positive (67% for both small and large cell lung cancers, 50% SCC and adenocarcinoma, 33% NSCLC). In the larger groups overall survival was worse in those testing positive (474 versus 844 days in SCC and 54 versus 749 days in adenocarcinoma patients). Most importantly the time from a positive test to the clinical diagnosis ranged from 2.72 years for small cell, 3.13 for adenocarcinoma, 5.07 for NSCLC, 6.07 for SSC, and 6.24 for large cell cancer). In excluded cases where lung cancer was believed to be metastatic 75% of cancers were positive. Conclusions: At a projected real world sensitivity of 0.53 and specificity of 0.82 and the ability to predate diagnosis by up to 4.7 years overall, this test could help direct lung cancer screening. In addition, the Adnab-9 testing selectively detects worse tumor types (67%) and those with worse prognosis amongst the more common, favorable phenotypes thus making early diagnosis possible in those patients who stand to benefit most from this strategy. Metastatic lung cancer also detected by the test should be identified by the follow-up imaging studies and therefore would not be considered to be a major pitfall. Citation Format: Martin Tobi, Yosef Y. Tobi, Fadi Antaki, MaryAnn Rambus, Michael Lawson. Preliminary data of a stool test for lung cancer from a prospective study [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4519.