Open AccessEfficacy of Pyrotinib in a Heavily Pretreated Patient with Lung Adenocarcinoma Harboring HER2 Amplification and Exon 20 Insertions: A Case Report
Author(s) -
Jianzhen Shan,
Jian Ruan,
Yinuo Tan,
Yan Li,
Songan Chen,
Miaoyan Du,
Lingjie Wang
Publication year - 2020
Publication title -
oncotargets and therapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.054
H-Index - 60
ISSN - 1178-6930
DOI - 10.2147/ott.s271999
Subject(s) - medicine , afatinib , adenocarcinoma , lung cancer , oncology , exon , pleural effusion , lung , cancer research , cancer , gene , gefitinib , epidermal growth factor receptor , biology , genetics
The clinical benefits of HER2 inhibitors in patients with non-small cell lung cancer (NSCLC) have been limited. There is a paucity of effective therapies in NSCLC after developing resistance to initial anti-HER2 therapy. Herein, we presented the clinical benefit of pyrotinib in a 53-year-old patient with advanced lung adenocarcinoma whose circulating tumor DNA (ctDNA) analysis of pleural effusion revealed the coexistence of HER2 exon 20 p.Y772_A775dup (mutation ratio: 38.86%) and HER2 amplification (copy number: 4.5) following failures of multiple therapies including afatinib and ado-trastuzumab emtansine (T-DM1). Notably, pyrotinib treatment induced rapid and marked improvement of clinical symptoms, and partial response was observed after 8 weeks. CtDNA monitoring during the treatment showed that the mutation ratio of HER2 decreased to 7.99%, and the amplification disappeared. The patient achieved a progression-free survival of 7.5 months after treatment with pyrotinib. Thus, pyrotinib may be a new treatment strategy for the subgroup of lung adenocarcinoma patients, with coexistence of HER2 exon 20 p.Y772_A775dup and HER2 amplification even after failures of multiple anti-HER2 therapies. It also indicated the value of capture-based next-generation sequencing to monitor and guide therapy.