Patients with Lung Adenocarcinoma, Exon20ins May Not Respond to TKI Therapy

Many patients with advanced lung adenocarcinoma who have EGFR exon20ins may not respond to EGFR tyrosine kinase inhibitors (TKI) therapy, according to a recent study published online ahead of print in Cancer.

Researchers led by Jarushka Naidoo, MB, BCH, BAO, of the Memorial Sloan Kettering Cancer Center looked at 1,882 patients with stage IV lung adenocarcinomas. They measured overall survival from time of diagnoses of stage IV disease in those patients treated with EGFR TKI erlotinib.

Using routine molecular testing, they identified 46 patients with EGFR exon20ins, with 258 patients who had an EGFR exon 19 deletion/L858R point mutation.

They found that among 11 patients with lung adenocarcinomas with EGFR exon20ins who received erlotinib, three of them had partial response.

Response to chemotherapy was similar between patients with EGFR exon20ins and patients with EGFR exon19del/L858R, with median overall survival from diagnosis found to be 26 months and 31 months, respectively.

“These patients have an overall survival similar to that of patients with sensitizing EGR mutations,” the authors concluded. “Standard chemotherapy should be used as first-line therapy.”

Reference

1. Naidoo, J., Sima, C. S., Rodriguez, K., Busby, N., Nafa, K., Ladanyi, M., Riely, G. J., Kris, M. G., Arcila, M. E. and Yu, H. A. (2015), Epidermal growth factor receptor exon 20 insertions in advanced lung adenocarcinomas: Clinical outcomes and response to erlotinib. Cancer. doi: 10.1002/cncr.29493