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Simple Summary: Targeted therapies have revolutionized the treatment of patients with non-small cell lung cancer (NSCLC). Adenocarcinoma, the most common histological subtype of NSCLC, is the posterchild of this therapeutic approach because of its high rate of treatable targets. In our study, we provide evidence that squamous cell carcinoma (SCC), the second most common histological subtype of NSCLC, also harbors a significant number of treatable targets, although at a lower rate than adenocarcinoma. Furthermore, we show that most SCC patients harboring such an alteration were >50 years of age and current or former smokers, questioning restrictive molecular testing strategies. Based on our data, we propose that broad molecular profiling should be performed in all newly diagnosed NSCLC cases, irrespective of histological subtype, but also irrespective of age or smoking status. Due to the success story of biomarker-driven targeted therapy, most NSCLC guidelines agree that molecular reflex testing should be performed in all cases with non-squamous cell carcinoma (non-SCC). In contrast, testing recommendations for squamous cell carcinoma (SCC) vary considerably, specifically concerning the exclusion of patients of certain age or smoking status from molecular testing strategies. We performed a retrospective single-center study examining the value of molecular reflex testing in an unselected cohort of 316 consecutive lung SCC cases, tested by DNA- and RNA-based next-generation sequencing (NGS) at our academic institution between 2019 and 2023. Clinicopathological data from these cases were obtained from electronic medical records and correlated with sequencing results. In 21/316 (6.6%) cases, we detected an already established molecular target for an approved drug. Among these were seven cases with an EGFR mutation, seven with a KRAS G12C mutation, four with an ALK fusion, two with an EGFR fusion and one with a METex14 skipping event. All patients harboring a targetable alteration were >50 years of age and most of them had >15 pack-years, questioning restrictive molecular testing strategies. Based on our real-world data, we propose a reflex testing workflow using DNA- and RNA-based NGS that includes all newly diagnosed NSCLC cases, irrespective of histology, but also irrespective of age or smoking status. [ABSTRACT FROM AUTHOR]