Frequency of anaplastic lymphoma kinase rearrangements in Moroccan patients with non small cell lung cancer: a multi-institutional national retrospective study

BACKGROUND: Anaplastic lymphoma kinase (ALK) rearrangement is a predictive factor of response to ALK inhibitors in non small cell lung cancer (NSCLC). The prevalence of ALK rearrangements is well known in Whites and Asians. However, data identifying the frequency of this rearrangement in Moroccan and North African population are lacking. The objective of this study is to report the frequency of ALK rearrangement in a group of Moroccan patients with NSCLC. METHODS: A retrospective study was performed enrolling 120 Moroccan patients with NSCLC whose biopsy samples were tested for ALK rearrangement in order to identify the frequency of ALK rearrangement and its potential association with selected variables. The ALK testing was established using fluorescent in situ hybridization (FISH) or immunohistochemistry (IHC). RESULTS: The frequency of ALK rearrangement was 4.2% (5/120). All positive cases were males with advanced adenocarcinoma. ALK rearrangements prevalence was significantly higher in older patients. CONCLUSIONS: The frequency of ALK rearrangements among the Moroccan population tends to correlate with the average frequency reported worldwide, with some specific features. Further prospective studies with larger patients’ numbers are needed to verify these findings.