Screening for Anaplastic Lymphoma Kinase (ALK) gene rearrangements in non-small cell lung cancer (NSCLC) in New Zealand.

Abstract

BACKGROUND:Lung cancer is a major cause of death in New Zealand. In recent years, targeted therapies have improved outcomes. AIM:To determine the uptake of ALK testing, and the prevalence, demographic profile and outcomes of ALK-positive NSCLC, in NZ, where no national ALK-testing guidelines or subsidized ALK tyrosine kinase inhibitor (TKI) therapies are available. METHODS:A population-based observational study reviewed databases to identify patients presenting with nonsquamous NSCLC over 6.5 years in northern NZ. We report the proportion tested for ALK gene rearrangements and the results. NSCLC samples tested by Fluorescence In Situ Hybridisation (FISH) were retested by Next Generation Sequencing (NGS) and ALK immunohistochemistry (IHC). A survival analysis compared ALK-positive patients treated or not treated with ALK TKI therapy. RESULTS:From a total of 3130 patients diagnosed with nonsquamous NSCLC, 407 (13%) were tested for ALK gene rearrangements, and patient selection was variable and inequitable. Among those tested, 34 (8.4%) had ALK-positive NSCLC. ALK-positive disease was more prevalent in younger versus older patients, nonsmokers versus smokers, and in MĀori, Pacific or Asian ethnic groups than in NZ Europeans. FISH, IHC and NGS showed broad concordance for detecting ALK-positive disease under local testing conditions. Among patients with ALK-positive metastatic NSCLC, those treated with ALK TKIs survived markedly longer than those not treated with ALK TKIs (median overall survival 5.12 versus 0.55 years). CONCLUSION:Lung cancer outcomes in NZ may be improved by providing national guidelines and funding policy for ALK testing and access to subsidized ALK TKI therapy. This article is protected by copyright. All rights reserved.