Additionally, in the LUX-Lung 8 clinical trial, which included patients with stage IIIB/IV lung squamous cell carcinoma progressing after platinum-based chemotherapy, patients with ERBB4 mutations showed a trend toward better PFS [HR = 0.21 (0.02–1.94)] and OS [HR = 0.22 (0.05–1.04)] when treated with afatinib than erlotinib; however, the number of patients in this subgroup was small (n = 14), and other treatment comparators were lacking160. Here, ERBB4 is linked to squamous cell lung carcinoma.