415P - Real-world fusion landscape of RET gene fusions and its response to cabozantinib in Chinese non-small cell lung cancer (NSCLC) using next generation sequencing

Background

RET fusion is one of the rare driver genes in lung cancer and thyroid carcinoma and and RET-directed therapies have shown promising results in this unique population. The aim of this study was to investigate the efficacy of cabozantinib in patients with advanced RET fusion NSCLC.

Methods

A multicenter study in China was initiated from February 2014, and NSCLC patients have been enrolled as of December 2019. To determine the frequency of the RET fusions in NSCLC and other tumors, we analyzed data from 3046 clinical NSCLC cases, each of which had results from next-generation sequencing (NGS)-based 381 genes panel assay, analogous to the index patient.

Results

Of this entire cohort, 61 (2.00%) patients were identified with a RET fusion, including KIF5B-RET (40), CCDC6-RET (16), NCOA4-RET (1), ANK3-RET (1), ERC1-RET (1), RYFY2-RET (1) and CSGALNACT2-RET (1). 8 cases coexist with EGFR mutations, were all used EGFR-TKIs treatment. For treatments, 14.75% (9/61) patients chose cabozantinib, other patients chose chemotherapy or chemoradiotherapy, and case examples of advanced RET fusion driven NSCLC patients responding to cabozantinib were actively being sought thru our database.

Conclusions

Patients with advanced RET fusion NSCLC showed a relatively good outcome of cabozantinib with relatively large side effects, which strengthen the need for effective RET-targeted drugs in clinical practice.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

Chun-wei Xu.

Funding

Has not received any funding.

Disclosure

All authors have declared no conflicts of interest.