ATF3 and neoplasm: <h4>Background</h4>ATF3 was found to play a complex role in various cancers; however, its systematic function in kidney renal clear cell carcinoma (KIRC) and across pan-cancer contexts remained incompletely understood.<h4>Methods</h4>A comprehensive evaluation of ATF3 expression, diagnostic efficacy, prognostic relevance, and its association with the tumor immune microenvironment was conducted across multiple cancer types using publicly available databases.