Successful Treatment with Crizotinib to Overcome Drug Resistance Possibly Due to Mesenchymal-epithelial Transition Amplification in a Lung Cancer Patient with the Echinoderm Microtubule-associated Protein-like 4-anaplastic Lymphoma Kinase Fusion Gene

Combinatorial therapy is a safe and durable treatment option in ALK-rearranged non-small cell lung cancer with an acquired MET exon 14 skipping mutation mediated resistance to alectinib: a case report

Background

Anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKIs) are standard first line treatment for ALK-rearranged non-small cell lung cancer (NSCLC) and have demonstrated high and durable response rates. Despite these initial responses, patients eventually develop resistance through ALK dependent and ALK independent alterations. These resistance mechanisms have made treatment decisions increasingly more complex. Here we describe a case of an acquired mesenchymal epithelial transition factor (MET) exon 14 skipping (METex14) mutation mediated resistance to alectinib in a patient with ALK-rearranged lung adenocarcinoma.

Case Description

We present a 72-year-old male with a 2-pack year smoking history and end-stage renal disease on hemodialysis diagnosed with metastatic lung adenocarcinoma harboring an echinoderm microtubule-associated protein 4 (EML4)-ALK fusion gene mutation. The patient was initially treated with alectinib with good response. However, the patient eventually developed resistance. Next generation sequencing of a liquid biopsy at time of progression revealed a MET exon 14 skip mutation. The patient was started on dual alectinib and capmatinib therapy, which led to a rapid and durable response.

Conclusions

This is the first case report of the successful treatment of METex14 mutation mediated resistance to alectinib with combination therapy of alectinib and capmatinib, which led to a rapid and durable response in our patient. This case highlights the importance of resequencing patients at the time of progression to identify potential actionable ALK dependent and independent resistance alterations. Combinatorial therapy may provide a promising effective and safe therapy option for patients who acquire resistance after initial TKI therapy.

Anaplastic lymphoma kinase inhibitors-a review of anticancer properties, clinical efficacy, and resistance mechanisms

Fusions and mutations of anaplastic lymphoma kinase (ALK), a tyrosine kinase receptor, have been identified in several neoplastic diseases. Rearranged ALK is a driver of tumorigenesis, which activates various signaling pathway associated with proliferation and survival. To date, several agents that target and inhibit ALK have been developed. The most studied ALK-positive disease is non-small cell lung cancer, and three generations of ALK tyrosine kinase inhibitors (TKIs) have been approved for the treatment of metastatic disease. Nevertheless, the use of ALK-TKIs is associated with acquired resistance (resistance mutations, bypass signaling), which leads to disease progression and may require a substitution or introduction of other treatment agents. Understanding of the complex nature and network of resistance mutations may allow to introduce sequential and targeted therapies. In this review, we aim to summarize the efficacy and safety profile of ALK inhibitors, describe off-target anticancer effects, and discuss resistance mechanisms in the context of personalized oncology.