ALK and non-small cell lung carcinoma: However, ALK rearrangements were mainly enriched in nonsmoking or smoking limited patients (49, 50), which was consistent with the aforementioned low TMB expression in ALK rearranged lung cancer, which led to the possibility that such tumours might have fewer neoantigens capable of generating immune responses, which might be one of the reasons affecting the efficacy of immunotherapy in patients with ALK rearranged NSCLC.