PT  - JOURNAL ARTICLE
AU  - TAKASHI KIJIMA
AU  - TAKAAKI ARIGAMI
AU  - YOSHIKAZU UENOSONO
AU  - TSUBASA HIRAKI
AU  - SHIGEHIRO YANAGITA
AU  - DAISUKE MATSUSHITA
AU  - KEISHI OKUBO
AU  - MASATAKA SHIMONOSONO
AU  - SUMIYA ISHIGAMI
AU  - KOSEI MAEMURA
AU  - AKIHIDE TANIMOTO
AU  - SHOJI NATSUGOE
TI  - Comparison of HER2 Status Before and After Trastuzumab-based Chemotherapy in Patients With Advanced Gastric Cancer
AID  - 10.21873/anticanres.13927
DP  - 2020 Jan 01
TA  - Anticancer Research
PG  - 75--80
VI  - 40
IP  - 1
4099  - http://ar.iiarjournals.org/content/40/1/75.short
4100  - http://ar.iiarjournals.org/content/40/1/75.full
SO  - Anticancer Res2020 Jan 01; 40
AB  - Background/Aim: The aim of the present study was to compare human epidermal growth factor receptor 2 (HER2) expression before and after trastuzumab-based chemotherapy in patients with advanced HER2-positive gastric cancer. Materials and Methods: We assessed HER2 expression using immunohistochemistry and/or fluorescence in situ hybridization in pre-treatment biopsied specimens and post-treatment resected specimens obtained from seven patients with advanced HER2-positive gastric cancer receiving trastuzumab-based chemotherapy. Results: Four patients maintained the HER2-positive status and three patients had a change in HER2 expression from positive to negative. In patients showing the loss of HER2 expression after treatments, HER2-positive tumor cells with a dominant histological type disappeared, and HER2-negative tumor cells with another dominant histological type were identified. Conclusion: HER2 expression can change after trastuzumab-based chemotherapy in patients with advanced HER2-positive gastric cancer. Continuous monitoring of HER2 expression after treatments may be utilized to determine whether the continued use of trastuzumab is advisable.