Abstract 3782: IASLC grading system predict distant metastases for resected lung adenocarcinoma

Abstract The International Association for the Study of Lung Cancer (IASLC) proposed a new histological grading system for invasive lung adenocarcinoma (LUAD). However, whether this new grading system is able to predict distant metastases in LUAD patients has not been evaluated. This study investigated the feasibility of using this grading system to predict the occurrence of brain and bone metastases in patients with resectable LUAD which identifies patients who have a high probability of developing distant metastases after surgery. We collected clinical information and pathological reports of 179 early stage LUAD patients who underwent resection during 2008 to 2015 from Wake Forest Comprehensive Cancer Center. All patients were followed up for 5 years and both bone and brain metastasis-free survival were calculated. Tumor grading of all samples was evaluated by both IASLC grading and predominant pattern-based grading systems. The ability of predicting distant metastases using IASLC grading and tumor stage were examined by receiver operating characteristic curves (ROC). 28 out of 179 patients developed distant metastases in five years with a median overall survival of 60 months for metastasis-free patients and 38. 9 for patients with distant metastasis. Compared to predominant pattern-based grading system, IASLC grading system showed a stronger correlation with distant metastasis incidence. Complex gland pattern is enriched in patients who developed bone and brain metastases compared to metastasis-free patients. IASLC grading system also showed a superior prediction power of distant metastasis compared to tumor stage with area under curve (AUC) of 0. 69 for brain metastasis and 0. 71 for bone metastasis. IASLC grading system is capable of predicting the incidence of distant metastasis among early-stage invasive LUAD patients. Citation Format: Yuezhu Wang, Margaret R. Smith, Yin Liu, Mary E. Green, Omer A. Hassan, Alexandra M. Balmaceda, Tammy Sexton, Wencheng Li, Fei Xing. IASLC grading system predict distant metastases for resected lung adenocarcinoma abstract. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts) ; 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84 (6Suppl): Abstract nr 3782.