Anaplastic lymphoma kinase rearrangements in patients with non-small cell lung cancer in Jordan.

OBJECTIVE

Anaplastic lymphoma kinase () rearrangement is an important oncogenic driver in some non-small cell lung cancers (NSCLC). Treatment with ALK tyrosine kinase inhibitors improves survival. The availability of diagnostic immunohistochemistry (IHC) has led to a paradigm shift in ALK testing. This study examined the prevalence of rearrangement in Jordanian patients with NSCLC and compared the results of IHC and fluorescence in situ hybridization (FISH) for detecting rearrangement.

METHODS

This retrospective study on 449 patients with NSCLC treated at the King Hussein Cancer Center in Jordan tested biopsy samples for rearrangement using FISH and/or IHC (D5F3) between 2018 and 2020.

RESULTS

Eighteen patients (4%) had ALK-positive NSCLC. The calculated sensitivity and specificity of ALK immunostaining compared with FISH were 87.5% and 96%, respectively. ALK-positive patients were significantly younger than their ALK-negative counterparts, and women were three times more likely to carry rearrangement than men. rearrangement was significantly associated with smoking history, with most ALK-positive patients being non-smokers, former smokers, or light smokers.

CONCLUSIONS

IHC is a reasonable alternative to FISH for ALK testing with advantages in terms of robustness, turnaround times, and cost-effectiveness.