As shown in Fig. 5, the distribution of tumor sites with initial progressive disease after first-line EGFR-TKIs treatment failure were generally similar among the three groups, except that there were more patients with cranial PD in the uncommon EGFR mutation group (31.1%) than that in the 19del group (9.2%) or L858R group (13.6%) (p < 0.001). The gene discussed is EGFR; the disease is neoplasm.