Abstract
Background: HER2 overexpression and/or amplification has been reported as predictive factor to HER2 targeted therapy in breast and gastric cancer, whereas HER3 is emerging as a potential resistance factor. The aim of this study was to perform a systematic review and meta-analysis of the HER2 and HER3 up-regulation in biliary tract cancers (BTCs).
Methods: An electronic search of MEDLINE, ASCO, ESMO and AACR was performed to identify studies reporting HER2 and/or HER3 membrane protein expression by immunohistochemistry (IHC) and/or gene amplification by in situ hybridisation (ISH) in BTCs.
Results: Out of 440 studies screened, 40 met the inclusion criteria. Globally, HER2 expression rate was 26.5% (95% CI, 18.9% - 34.1%). Studies were classified as “high-quality” (HQ; 27 studies) [IHC overexpression defined as presence of moderate/strong staining] and “low-quality” (11 studies) [“any” expression was considered positive]. When HQ studies were analysed, extra-hepatic BTCs (EH-BTCs) showed a higher HER2 overexpression rate compared to intrahepatic cholangiocarcinoma (IHCC) [19.9% (95% CI, 12.8 – 27.1%) vs. 4.8% (95% CI, 0 – 14.5%); p-value 0.0049]. HER2 amplification rate was higher in those patients selected by HER2 overexpression [57.6% (95% CI, 16.2 - 99%)] compared to “unselected” patients [17.9% (95% CI, 0.1 – 35.4%); p-value 0.0072]. HER3 overexpression (4/4 HQ studies) and amplification rates were 27.9% (95% CI, 9.7 - 46.1%) and 26.5% (one study), respectively.
Conclusions: Up to 20% of EH-BTCs might be HER2 overexpressed, ∼60% of HER2 overexpressed BTCs can be considered amplified while HER3 is overexpressed or amplified in ∼25% of BTCs. These findings may be considered in future trial development.
Methods: An electronic search of MEDLINE, ASCO, ESMO and AACR was performed to identify studies reporting HER2 and/or HER3 membrane protein expression by immunohistochemistry (IHC) and/or gene amplification by in situ hybridisation (ISH) in BTCs.
Results: Out of 440 studies screened, 40 met the inclusion criteria. Globally, HER2 expression rate was 26.5% (95% CI, 18.9% - 34.1%). Studies were classified as “high-quality” (HQ; 27 studies) [IHC overexpression defined as presence of moderate/strong staining] and “low-quality” (11 studies) [“any” expression was considered positive]. When HQ studies were analysed, extra-hepatic BTCs (EH-BTCs) showed a higher HER2 overexpression rate compared to intrahepatic cholangiocarcinoma (IHCC) [19.9% (95% CI, 12.8 – 27.1%) vs. 4.8% (95% CI, 0 – 14.5%); p-value 0.0049]. HER2 amplification rate was higher in those patients selected by HER2 overexpression [57.6% (95% CI, 16.2 - 99%)] compared to “unselected” patients [17.9% (95% CI, 0.1 – 35.4%); p-value 0.0072]. HER3 overexpression (4/4 HQ studies) and amplification rates were 27.9% (95% CI, 9.7 - 46.1%) and 26.5% (one study), respectively.
Conclusions: Up to 20% of EH-BTCs might be HER2 overexpressed, ∼60% of HER2 overexpressed BTCs can be considered amplified while HER3 is overexpressed or amplified in ∼25% of BTCs. These findings may be considered in future trial development.
Original language | English |
---|---|
Title of host publication | Annals of Oncology |
Place of Publication | Annals of Oncology |
Volume | 27 |
Edition | 6 |
Publication status | Published - Oct 2016 |
Keywords
- biliary tract cancer, cholangiocarcinoma, HER2 pathway, HER3 pathway, systematic review, metaanalysis
Research Beacons, Institutes and Platforms
- Manchester Cancer Research Centre