REFERENCES
1. Ieni A, Barresi V, Caltabiano R, Cascone AM, Del Sordo R, Cabibi D, Zeppa P, Lanzafame S, Sidoni A, Franco V, Tuccari G. Discordance rate of HER2 status in primary breast carcinomas versus synchronous axillary lymph node metastases: a multicenter retrospective investigation. Onco Targets Ther 2014;7:1267-72.
2. Ieni A, Barresi V, Giuffrè G, Caltabiano R, Cascone A, Del Sordo R, Cabibi D, Zeppa P, Lanzafame S, Sidoni A, Franco V, Tuccari G. Letter to the Editor regarding the paper by Aurilio et al. A meta-analysis of oestrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 discordance between primary breast cancer and metastases. Eur J Cancer 2014;50:1035-7.
3. Aitken SJ, Thomas JS, Langdon SP, Harrison DJ, Faratian D. Quantitative analysis of changes in ER, PR and HER2 expression in primary breast cancer and paired nodal metastases. Ann Oncol 2010;21:1254-61.
4. Chan A, Morey A, Brown B, Hastrich D, Willsher P, Ingram D. A retrospective study investigating the rate of HER2 discordance between primary breast carcinoma and locoregional or metastatic disease. BMC Cancer 2012;12:555.
5. Hoefnagel LD, Moelans CB, Meijer SL, van Slooten HJ, Wesseling P, Wesseling J, Westenend PJ, Bart J, Seldenrijk CA, Nagtegaal ID, Oudejans J, van der Valk P, van Gils CH, van der Wall E, van Diest PJ. Prognostic value of estrogen receptor α and progesterone receptor conversion in distant breast cancer metastases. Cancer 2012;118:4929-35.
6. Aurilio G, Disalvatore D, Pruneri G, Bagnardi V, Viale G, Curigliano G, Adamoli L, Munzone E, Sciandivasci A, De Vita F, Goldhirsch A, Nolè F. A meta-analysis of oestrogen receptor, progesterone receptor and human epidermal growth factor receptor 2 discordance between primary breast cancer and metastases. Eur J Cancer 2014;50:277-89.
7. Curtit E, Nerich V, Mansi L, Chaigneau L, Cals L, Villanueva C, Bazan F, Montcuquet P, Meneveau N, Perrin S, Algros MP, Pivot X. Discordances in estrogen receptor status, progesterone receptor status, and HER2 status between primary breast cancer and metastasis. Oncologist 2013;18:667-74.
8. Penault-Llorca F, Coudry RA, Hanna WM, Osamura RY, Rüschoff J, Viale G. Experts' opinion: Recommendations for retesting breast cancer metastases for HER2 and hormone receptor status. Breast 2013;22:200-2.
9. Regitnig P, Schippinger W, Lindbauer M, Samonigg H, Lax SF. Change of HER-2/neu status in a subset of distant metastases from breast carcinomas. J Pathol 2004;203:918-26.
10. Santinelli A, Pisa E, Stramazzotti D, Fabris G. HER-2 status discrepancy between primary breast cancer and metastatic sites. Impact on target therapy. Int J Cancer 2008;122:999-1004.
11. Lindström LS, Karlsson E, Wilking UM, Johansson U, Hartman J, Lidbrink EK, Hatschek T, Skoog L, Bergh J. Clinically used breast cancer markers such as estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 are unstable throughout tumor progression. J Clin Oncol 2012;30:2601-8.
12. Houssami N, Macaskill P, Balleine RL, Bilous M, Pegram MD. HER2 discordance between primary breast cancer and its paired metastasis: tumor biology or test artefact? Insights through meta-analysis. Breast Cancer Res Treat 2011;129:659-74.
13. Cardoso F, Harbeck N, Fallowfield L, Kyriakides S, Senkus E. ESMO Guidelines Working Group. Locally recurrent or metastatic breast cancer: ESMO Clinical Practice Guidelines for diagnosis, treatment and follow-up. Ann Oncol 2012;23 Suppl 7:vii11-9.
14. Pérez-Fidalgo JA, Eroles P, Ferrer J, Bosch A, Burgués O, Martínez F, Bermejo B, Lluch A, González-Angulo AM. An evaluation of the impact of technical bias on the concordance rate between primary and recurrent tumors in breast cancer. Breast 2013;22:974-9.
15. Turner NH, Di Leo A. HER2 discordance between primary and metastatic breast cancer: assessing the clinical impact. Cancer Treat Rev 2013;39:947-57.
16. Idirisinghe PK, Thike AA, Cheok PY, Tse GM, Lui PC, Fook-Chong S, Wong NS, Tan PH. Hormone receptor and c-ERBB2 status in distant metastatic and locally recurrent breast cancer. Pathologic correlations and clinical significance. Am J Clin Pathol 2010;133:416-29.
17. Kim JH, Kim MA, Lee HS, Kim WH. Comparative analysis of protein expressions in primary and metastatic gastric carcinomas. Hum Pathol 2009;40:314-22.
18. Rüschoff J, Dietel M, Baretton G, Arbogast S, Walch A, Monges G, Chenard MP, Penault-Llorca F, Nagelmeier I, Schlake W, Höfler H, Kreipe HH. HER2 diagnostics in gastric cancer-guideline validation and development of standardized immunohistochemical testing. Virchows Arch 2010;457:299-307.
19. Kim MA, Lee HJ, Yang HK, Bang YJ, Kim WH. Heterogeneous amplification of ERBB2 in primary lesions is responsible for the discordant ERBB2 status of primary and metastatic lesions in gastric carcinoma. Histopathology 2011;59:822-31.
20. Rüschoff J, Hanna W, Bilous M, Hofmann M, Osamura RY, Penault-Llorca F, van de Vijver M, Viale G. HER2 testing in gastric cancer: a practical approach. Mod Pathol 2012;25:637-50.
21. Giuffrè G, Ieni A, Barresi V, Caruso RA, Tuccari G. HER2 status in unusual histological variants of gastric adenocarcinomas. J Clin Pathol 2012;65:237-41.
22. Barresi V, Giuffrè G, Caruso RA, Tuccari G. HER2 status in rarer histologic types of gastric adenocarcinomas. Arch Pathol Lab Med 2013;137:741.
23. Bozzetti C, Negri FV, Lagrasta CA, Crafa P, Bassano C, Tamagnini I, Gardini G, Nizzoli R, Leonardi F, Gasparro D, Camisa R, Cavalli S, Silini EM, Ardizzoni A. Comparison of HER2 status in primary and paired metastatic sites of gastric carcinoma. Br J Cancer 2011;104:1372-6.
24. Kochi M, Fujii M, Masuda S, Kanamori N, Mihara Y, Funada T, Tamegai H, Watanabe M, Suda H, Takayama T. Differing deregulation of HER2 in primary gastric cancer and synchronous related metastatic lymph nodes. Diagn Pathol 2013;8:191.
25. Marx AH, Tharun L, Muth J, Dancau AM, Simon R, Yekebas E, Kaifi JT, Mirlacher M, Brümmendorf TH, Bokemeyer C, Izbicki JR, Sauter G. HER-2 amplification is highly homogenous in gastric cancer. Hum Pathol 2009;40:769-77.
26. Hofmann M, Stoss O, Shi D, Büttner R, van de Vijver M, Kim W, Ochiai A, Rüschoff J, Henkel T. Assessment of a HER2 scoring system for gastric cancer: results from a validation study. Histopathology 2008;52:797-805.
27. Ataseven B, Gologan D, Gunesch A, Kehl V, Hoegel B, Beer M, Eiermann W. HER2/neu, Topoisomerase 2a, Estrogen and Progesterone Receptors: Discordance between Primary Breast Cancer and Metastatic Axillary Lymph Node in Expression and Amplification Characteristics. Breast Care (Basel) 2012;7:465-70.
28. Falck AK, Bendahl PO, Chebil G, Olsson H, Fernö M, Rydén L. Biomarker expression and St Gallen molecular subtype classification in primary tumours, synchronous lymph node metastases and asynchronous relapses in primary breast cancer patients with 10 years' follow-up. Breast Cancer Res Treat 2013;140:93-104.