Diverse clinical outcomes for the EGFR‑mutated and ALK‑rearranged advanced non‑squamous non‑small cell lung cancer.

EGFR and ALK are key driver mutations in non-small cell lung cancer (NSCLC). Tyrosine kinase inhibitors are recommended as the first-line treatment for advanced NSCLC with driving oncogenes because they have fewer side effects and provide better disease control than chemotherapy. The present retrospective analysis aimed to investigate how altered driver genes impact cancer outcomes and clinical presentation. A total of 628 patients with advanced-stage NSCLC and documented EGFR and ALK mutations were enrolled at Changhua Christian Hospital in Taiwan between August 2011 and January 2021. EGFR mutations were identified by PCR. ALK rearrangements were identified by immunostaining. Patients without EGFR or ALK mutations were labeled as wild-type (WT). EGFR mutation was detected in 446 (71.02%) patients, ALK rearrangement in 36 (5.73%) patients and WT in 146 (23.25%) patients. EGFR mutations resulted in higher frequency of lung, brain and multiple extrapulmonary metastases than ALK rearrangement. The ALK group exhibited the longest median overall survival (OS), followed by EGFR and WT groups (ALK: 51.60±13.32, EGFR: 24.03±1.22 and WT: 19.63±2.43 months, respectively; P=0.011). In patients with brain metastases, ALK group had a longer median OS than the EGFR group. Because there were few recruited patients with ALK rearrangement, the results were not significant. According to the results of Cox regression model analysis, driver mutations with EGFR and ALK, lower smoking pack-years, younger age, better performance status, no pleural metastasis and fewer extrapulmonary metastases were key prognostic factors. In conclusion, diverse clinical outcomes are driven by different driver mutations. EGFR mutation leads to more extrapulmonary metastases. Median OS was superior in ALK-rearranged NSCLC than EGFR-mutated NSCLC regardless of brain metastases.