Novel PPFIA1-ALK, ALK-C2orf91(intergenic) double-fusion responded well to alectinib in an advanced lung adenocarcinoma patient: a case report

Abstract

Non-small cell lung cancers (NSCLCs) with anaplastic lymphoma kinase (ALK)-rearrangement have favorable responses to ALK inhibitors. However, ALK fusion mutations harbored approximately 90 distinct fusion partners. Patients with different ALK fusions might respond distinctly to different-generation ALK inhibitors. In this case report, we identified a novel non-reciprocal ALK fusion, ALK-C2orf91(intergenic) (A19: intergenic) and PPFIA1-ALK (P2:A20), by next-generation DNA sequencing in an advanced lung adenocarcinoma patient. After 2 months of alectinib, the targeted lung lesion regressed significantly, and evaluation of therapeutic efficiency indicated partial response. To date, the patient had achieved 12 months of progression-free survival from alectinib treatment. Our study extended the spectrum of ALK fusion partners in ALK-positive NSCLC, and we reported a new ALK fusion, PPFIA1-ALK and ALK-C2orf91(intergenic), and its sensitivity to alectinib firstly in lung cancer. We believe that this case report has an important clinical reference.