PURPOSE: Measurement of human epidermal growth factor receptor 2 (HER2) gene amplification in cell-free DNA (cfDNA) is an evolving technique in breast cancer, enabling liquid biopsies and treatment monitoring. The present study investigated the dynamics of plasma HER2 gene copy number and amplification in cfDNA during neoadjuvant chemotherapy. PATIENTS AND METHODS: The study included 50 patients from a prospective cohort analyzed during neoadjuvant chemotherapy. Fifty healthy women with no history of cancer served as control group and 15 patients with metastatic breast cancer were used to validate the assay. Total cfDNA and HER2 gene amplification were measured by quantitative real-time polymerase chain reaction. RESULTS: Plasma HER2 gene copy number (p = 0.794), HER2 gene amplification (p = 0.127) and total cfDNA (p = 0.440) did not differ significantly from the levels in the control group. Eighteen patients (36 %) obtained pathological complete response (pCR). HER2 gene copy number before the operation was significantly higher than the baseline level (p < 0.0001), but there was no difference between patients with and without pCR (p = 0.569). Likewise, there was no difference in plasma HER2 gene amplification between tissue HER2-positive and -negative patients (p = 0.754). CONCLUSIONS: The results indicate that neither total cfDNA nor HER2 gene copy number is elevated in primary breast cancer patients compared to healthy controls. The level of both parameters increased during neoadjuvant chemotherapy, but without any relation to treatment effect. There was no indication of plasma HER2 gene amplification in the HER2-positive patients in the neoadjuvant setting.
PURPOSE: Measurement of human epidermal growth factor receptor 2 (HER2) gene amplification in cell-free DNA (cfDNA) is an evolving technique in breast cancer, enabling liquid biopsies and treatment monitoring. The present study investigated the dynamics of plasma HER2 gene copy number and amplification in cfDNA during neoadjuvant chemotherapy. PATIENTS AND METHODS: The study included 50 patients from a prospective cohort analyzed during neoadjuvant chemotherapy. Fifty healthy women with no history of cancer served as control group and 15 patients with metastatic breast cancer were used to validate the assay. Total cfDNA and HER2 gene amplification were measured by quantitative real-time polymerase chain reaction. RESULTS: Plasma HER2 gene copy number (p = 0.794), HER2 gene amplification (p = 0.127) and total cfDNA (p = 0.440) did not differ significantly from the levels in the control group. Eighteen patients (36 %) obtained pathological complete response (pCR). HER2 gene copy number before the operation was significantly higher than the baseline level (p < 0.0001), but there was no difference between patients with and without pCR (p = 0.569). Likewise, there was no difference in plasma HER2 gene amplification between tissue HER2-positive and -negative patients (p = 0.754). CONCLUSIONS: The results indicate that neither total cfDNA nor HER2 gene copy number is elevated in primary breast cancerpatients compared to healthy controls. The level of both parameters increased during neoadjuvant chemotherapy, but without any relation to treatment effect. There was no indication of plasma HER2 gene amplification in the HER2-positive patients in the neoadjuvant setting.
Authors: Raquel Catarino; Maria M Ferreira; Helena Rodrigues; Ana Coelho; Ana Nogal; Abreu Sousa; Rui Medeiros Journal: DNA Cell Biol Date: 2008-08 Impact factor: 3.311
Authors: J Bergqvist; J F Ohd; J Smeds; S Klaar; J Isola; H Nordgren; G P Elmberger; H Hellborg; J Bjohle; A-L Borg; L Skoog; J Bergh Journal: Ann Oncol Date: 2007-03-09 Impact factor: 32.976
Authors: Antonio C Wolff; M Elizabeth H Hammond; Jared N Schwartz; Karen L Hagerty; D Craig Allred; Richard J Cote; Mitchell Dowsett; Patrick L Fitzgibbons; Wedad M Hanna; Amy Langer; Lisa M McShane; Soonmyung Paik; Mark D Pegram; Edith A Perez; Michael F Press; Anthony Rhodes; Catharine Sturgeon; Sheila E Taube; Raymond Tubbs; Gail H Vance; Marc van de Vijver; Thomas M Wheeler; Daniel F Hayes Journal: J Clin Oncol Date: 2006-12-11 Impact factor: 44.544
Authors: Martine J Piccart-Gebhart; Marion Procter; Brian Leyland-Jones; Aron Goldhirsch; Michael Untch; Ian Smith; Luca Gianni; Jose Baselga; Richard Bell; Christian Jackisch; David Cameron; Mitch Dowsett; Carlos H Barrios; Günther Steger; Chiun-Shen Huang; Michael Andersson; Moshe Inbar; Mikhail Lichinitser; István Láng; Ulrike Nitz; Hiroji Iwata; Christoph Thomssen; Caroline Lohrisch; Thomas M Suter; Josef Rüschoff; Tamás Suto; Victoria Greatorex; Carol Ward; Carolyn Straehle; Eleanor McFadden; M Stella Dolci; Richard D Gelber Journal: N Engl J Med Date: 2005-10-20 Impact factor: 91.245
Authors: Edward H Romond; Edith A Perez; John Bryant; Vera J Suman; Charles E Geyer; Nancy E Davidson; Elizabeth Tan-Chiu; Silvana Martino; Soonmyung Paik; Peter A Kaufman; Sandra M Swain; Thomas M Pisansky; Louis Fehrenbacher; Leila A Kutteh; Victor G Vogel; Daniel W Visscher; Greg Yothers; Robert B Jenkins; Ann M Brown; Shaker R Dakhil; Eleftherios P Mamounas; Wilma L Lingle; Pamela M Klein; James N Ingle; Norman Wolmark Journal: N Engl J Med Date: 2005-10-20 Impact factor: 91.245