Siegel RL, Miller KD, Fuchs HE, Jemal A. Cancer statistics, 2022. CA Cancer J Clin. 2022;72(1):7–33.

Article  PubMed  Google Scholar 

Morris VK, Kennedy EB, Baxter NN, Benson AB, Cercek A, Cho M, et al. Treatment of metastatic colorectal cancer: ASCO guideline. J Clin Oncol. 2022;41(3):678–700.

Article  PubMed  Google Scholar 

Chong CR, Jänne PA. The quest to overcome resistance to EGFR-targeted therapies in cancer. Nat Med. 2013;19(11):1389–400.

Article  CAS  PubMed  PubMed Central  Google Scholar 

National Comprehensive Cancer Network® (NCCN). NCCN Clinical Practice Guidelines in Oncology. Colon Cancer (Version 1.2024). 29 January 2024. Available from: https://www.nccn.org/professionals/physician_gls/pdf/colon.pdf. Accessed 11 Mar 2024.

U.S. Food and Drug Administration. FDA grants accelerated approval to tucatinib with trastuzumab for colorectal cancer. 19 Jan 2023. Available from: https://www.fda.gov/drugs/resources-information-approved-drugs/fda-grants-accelerated-approval-tucatinib-trastuzumab-colorectal-cancer. Accessed 3 Aug 2023.

Hynes NE, Lane HA. ERBB receptors and cancer: the complexity of targeted inhibitors. Nat Rev Cancer. 2005;5(5):341–54.

Article  CAS  PubMed  Google Scholar 

Siena S, Sartore-Bianchi A, Marsoni S, Hurwitz HI, McCall SJ, Penault-Llorca F, et al. Targeting the human epidermal growth factor receptor 2 (HER2) oncogene in colorectal cancer. Ann Oncol. 2018;29(5):1108–19.

Article  CAS  PubMed  PubMed Central  Google Scholar 

Gong J, Cho M, Sy M, Salgia R, Fakih M. Molecular profiling of metastatic colorectal tumors using next-generation sequencing: a single-institution experience. Oncotarget. 2017;8(26):42198–213.

Article  PubMed  PubMed Central  Google Scholar 

Nam SK, Yun S, Koh J, Kwak Y, Seo AN, Park KU, et al. BRAF, PIK3CA, and HER2 oncogenic alterations according to KRAS mutation status in advanced colorectal cancers with distant metastasis. PLoS ONE. 2016;11(3):e0151865.

Article  PubMed  PubMed Central  Google Scholar 

Ni S, Wang X, Chang J, Sun H, Weng W, Wang X, et al. Human epidermal growth factor receptor 2 overexpression and amplification in patients with colorectal cancer: a large-scale retrospective study in Chinese population. Front Oncol. 2022;12:842787.

Article  CAS  PubMed  PubMed Central  Google Scholar 

Richman SD, Southward K, Chambers P, Cross D, Barrett J, Hemmings G, et al. HER2 overexpression and amplification as a potential therapeutic target in colorectal cancer: analysis of 3256 patients enrolled in the QUASAR, FOCUS and PICCOLO colorectal cancer trials. J Pathol. 2016;238(4):562–70.

Article  CAS  PubMed  PubMed Central  Google Scholar 

Ross JS, Ali SM, Elvin JA, Schrock AB, Suh J, Vergilio J-A, et al. Targeted therapy for HER2 driven colorectal cancer. J Clin Oncol. 2017;35(15_suppl):3583.

Article  Google Scholar 

Salem ME, Weinberg BA, Xiu J, El-Deiry WS, Hwang JJ, Gatalica Z, et al. Comparative molecular analyses of left-sided colon, right-sided colon, and rectal cancers. Oncotarget. 2017;8(49):86356–68.

Article  PubMed  PubMed Central  Google Scholar 

Loree JM, Bailey AM, Johnson AM, Yu Y, Wu W, Bristow CA, et al. Molecular landscape of ERBB2/ERBB3 mutated colorectal cancer. J Natl Cancer Inst. 2018;110(12):1409–17.

Article  PubMed  PubMed Central  Google Scholar 

Ross JS, Fakih M, Ali SM, Elvin JA, Schrock AB, Suh J, et al. Targeting HER2 in colorectal cancer: the landscape of amplification and short variant mutations in ERBB2 and ERBB3. Cancer. 2018;124(7):1358–73.

Article  CAS  PubMed  Google Scholar 

Kavuri SM, Jain N, Galimi F, Cottino F, Leto SM, Migliardi G, et al. HER2 activating mutations are targets for colorectal cancer treatment. Cancer Discov. 2015;5(8):832–41.

Article  CAS  PubMed  PubMed Central  Google Scholar 

Valtorta E, Martino C, Sartore-Bianchi A, Penaullt-Llorca F, Viale G, Risio M, et al. Assessment of a HER2 scoring system for colorectal cancer: results from a validation study. Mod Pathol. 2015;28(11):1481–91.

Article  CAS  PubMed  Google Scholar 

Edenfield WJ, Chung KY, Gatalica Z, Basu GD. Molecular profiling of HER2-positive colorectal cancer for identification of multiple potential drug targets. J Clin Oncol. 2014;32(15_suppl):e14508-e.

Article  Google Scholar 

Fujii S, Magliocco AM, Kim J, Okamoto W, Kim JE, Sawada K, et al. International harmonization of provisional diagnostic criteria for ERBB2-amplified metastatic colorectal cancer allowing for screening by next-generation sequencing panel. JCO Precis Oncol. 2020;4:6–19.

Article  PubMed  Google Scholar 

Shimada Y, Yagi R, Kameyama H, Nagahashi M, Ichikawa H, Tajima Y, et al. Utility of comprehensive genomic sequencing for detecting HER2-positive colorectal cancer. Hum Pathol. 2017;66:1–9.

Article  CAS  PubMed  Google Scholar 

Cenaj O, Ligon AH, Hornick JL, Sholl LM. Detection of ERBB2 amplification by next-generation sequencing predicts HER2 expression in colorectal carcinoma. Am J Clin Pathol. 2019;152(1):97–108.

Article  CAS  PubMed  Google Scholar 

Ross DS, Zehir A, Cheng DT, Benayed R, Nafa K, Hechtman JF, et al. Next-generation assessment of human epidermal growth factor receptor 2 (ERBB2) amplification status: clinical validation in the context of a hybrid capture-based, comprehensive solid tumor genomic profiling assay. J Mol Diagn: JMD. 2017;19(2):244–54.

Article  CAS  PubMed  PubMed Central  Google Scholar 

Bardelli A, Siravegna G, Sartore-Bianchi A, Nagy RJ, Mussolin B, Cassingena A, et al. Plasma HER2 (ERBB2) copy number to predict response to HER2-targeted therapy in metastatic colorectal cancer. J Clin Oncol. 2018;36(15_suppl):3506.

Article  Google Scholar 

Nakamura Y, Okamoto W, Kato T, Esaki T, Kato K, Komatsu Y, et al. Circulating tumor DNA-guided treatment with pertuzumab plus trastuzumab for HER2-amplified metastatic colorectal cancer: a phase 2 trial. Nat Med. 2021;27(11):1899–903.

Article  CAS  PubMed  PubMed Central  Google Scholar 

Takegawa N, Yonesaka K, Sakai K, Ueda H, Watanabe S, Nonagase Y, et al. HER2 genomic amplification in circulating tumor DNA from patients with cetuximab-resistant colorectal cancer. Oncotarget. 2016;7(3):3453–60.

Article  PubMed  Google Scholar 

Cohen SA, Liu MC, Aleshin A. Practical recommendations for using ctDNA in clinical decision making. Nature. 2023;619(7969):259–68.

Article  CAS  PubMed  Google Scholar 

Lee WS, Park YH, Lee JN, Baek JH, Lee TH, Ha SY. Comparison of HER2 expression between primary colorectal cancer and their corresponding metastases. Cancer Med. 2014;3(3):674–80.

Article  CAS  PubMed  PubMed Central  Google Scholar 

Shan L, Lv Y, Bai B, Huang X, Zhu H. Variability in HER2 expression between primary colorectal cancer and corresponding metastases. J Cancer Res Clin Oncol. 2018;144(11):2275–81.

Article  CAS  PubMed  Google Scholar 

Ye P, Li F, Wei Y, Zhang Y, Cui J, Dai R, et al. EGFR, HER2, and HER3 protein expression in paired primary tumor and lymph node metastasis of colorectal cancer. Sci Rep. 2022;12(1):12894.

Article  CAS  PubMed  PubMed Central  Google Scholar 

Cavanna L, Seghini P, Di Nunzio C, Orlandi E, Michieletti E, Stroppa EM, et al. Gastric cancer with brain metastasis and the role of human epidermal growth factor 2 status. Oncol Lett. 2018;15(4):5787–91.

PubMed  PubMed Central  Google Scholar 

Martin AM, Cagney DN, Catalano PJ, Warren LE, Bellon JR, Punglia RS, et al. Brain metastases in newly diagnosed breast cancer: a population-based study. JAMA Oncol. 2017;3(8):1069–77.

Article  PubMed  PubMed Central  Google Scholar 

Chen PC, Yeh YM, Chu CT, Su PF, Chiu PH, Lin BW, et al. HER2 amplification in colorectal cancer with brain metastasis: a propensity score matching study. Eur J Cancer (Oxford, England: 1990). 2023;181:62–9.

Article  CAS  Google Scholar 

Tan RYC, Camat MD, Ng M, Lim TH, Lim AST, Lim KH, et al. HER2 positive rates are enriched amongst colorectal cancer brain metastases: a study amongst 1920 consecutive patients. Ann Oncol. 2018;29(7):1598–9.

Article  CAS  PubMed  Google Scholar 

Li JL, Lin SH, Chen HQ, Liang LS, Mo XW, Lai H, et al. Clinical significance of HER2 and EGFR expression in colorectal cancer patients with ovarian metastasis. BMC Clin Pathol. 2019;19:3.

Article  CAS  PubMed  PubMed Central  Google Scholar 

Wu SW, Ma CC, Li WH. Does overexpression of HER-2 correlate with clinicopathological characteristics and prognosis in colorectal cancer? Evidence from a meta-analysis. Diagn Pathol. 2015;10:144.

Article  PubMed  PubMed Central  Google Scholar 

Laurent-Puig P, Balogoun R, Cayre A, Le Malicot K, Tabernero J, Mini E, et al. ERBB2 alterations a new prognostic biomarker in stage III colon cancer from a FOLFOX based adjuvant trial (PETACC8). Ann Oncol. 2016;27:vi151.

Google Scholar 

Ingold Heppner B, Behrens HM, Balschun K, Haag J, Krüger S, Becker T, et al. HER2/neu testing in primary colorectal carcinoma. Br J Cancer. 2014;111(10):1977–84.

Article  CAS  PubMed  PubMed Central