TTF1 and adenocarcinoma: Consistent with previous studies, most cases with SMARCA4‐NSCLCs and SMARCA4‐UTs were negative for squamous cell carcinoma and neuroendocrine markers (CK5/6, p40, chromogranin A, and CD56), and the vast majority of SMARCA4‐UTs (60%) were negative for adenocarcinoma marker TTF‐1, reinforcing their distinction from conventional NSCLC.19, 25, 26