Prognostic impact and distinctive characteristics of surgically resected anaplastic lymphoma kinase-rearranged lung adenocarcinoma.

OBJECTIVE

Anaplastic lymphoma kinase (ALK) rearrangement is a representative lung cancer with driver mutation because of the efficacy of ALK-tyrosine kinase inhibitors. ALK-tyrosine kinase inhibitors are extensively used for ALK-rearranged lung cancer, whereas the therapeutic benefit of surgery remains unclear. Thus, we aimed to assess the clinical benefit of surgery in ALK-rearranged lung cancer and to elucidate the oncologic characteristics of ALK-rearranged lung cancer through surgically resected cases.

METHODS

We retrospectively evaluated 1925 lung adenocarcinoma cases surgically resected between 1996 and 2017 at our institute. Moreover, 75 ALK-rearranged and 75 non-ALK-rearranged cases were extracted using propensity score matching. The survival rates, prognostic factors, and post-recurrence state were assessed.

RESULTS

Multivariable analysis revealed that ALK rearrangement was an independent prognostic factor for improved cancer-specific survival (hazard ratio, 0.2; 95% confidence interval, 0.05-0.88; P = .033). In the matched cohort, the 5-year cancer-specific survival rates after surgery in the ALK-rearranged and non-ALK-rearranged groups were 97% and 77%, respectively. The ALK-rearranged group had a significantly better cancer-specific survival than did the non-ALK-rearranged group (log-rank test; P = .003). With respect to post-recurrence state, oligo-recurrence was highly frequent in the ALK-rearranged group, and post-recurrence survival was significantly improved by administration of either ALK-tyrosine kinase inhibitors (log-rank test; P = .011) or local ablative therapies (log-rank test; P = .035).

CONCLUSIONS

Surgically resected ALK-rearranged lung adenocarcinoma has excellent long-term outcome. Not only ALK-tyrosine kinase inhibitors but also a combination of local and systemic therapies may be important treatment strategies for ALK-rearranged lung adenocarcinoma even in the post-recurrence state.