A novel fusion gene in a patient with metastatic lung adenocarcinoma and its response to crizotinib: a case report

Anaplastic lymphoma kinase ( ALK ) rearrangement occurs in approximately 5% of non-small cell lung cancers (NSCLCS), and EML4-ALK is the most commonly observed ALK fusion variant in NSCLC. However, growth hormone receptor ( GHR ) as the fusion partner for ALK and the clinical response to ALK tyrosine kinase inhibitors in patients with metastatic lung adenocarcinoma (LUAD) who carry the GHR-ALK variant have not been documented. This case describes a 63-year-old woman diagnosed with metastatic LUAD. Immunohistochemistry revealed positive ALK expression, and the patient was treated with crizotinib. After 3 weeks of treatment, the patient had a partial response. Because of treatment-related adverse events, the dose of crizotinib was reduced. After 3.7 months, computed tomography uncovered disease progression. Next-generation sequencing identified a novel GHR-ALK fusion in the plasma of the patient. The patient was treated again with crizotinib, but the disease progressed again 2 months later. Then, the patient received chemotherapy. She succumbed to her disease 11 months after the initial diagnosis. Our work provides evidence supporting the use of crizotinib in patients with metastatic LUAD harboring GHR-ALK .