Unknown

Dataset Information

0

The relationship between quantitative human epidermal growth factor receptor 2 gene expression by the 21-gene reverse transcriptase polymerase chain reaction assay and adjuvant trastuzumab benefit in Alliance N9831.


ABSTRACT: The N9831 trial demonstrated the efficacy of adjuvant trastuzumab for patients with human epidermal growth factor receptor 2 (HER2) locally positive tumors by protein or gene analysis. We used the 21-gene assay to examine the association of quantitative HER2 messenger RNA (mRNA) gene expression and benefit from trastuzumab.N9831 tested the addition of trastuzumab to chemotherapy in stage I-III HER2-positive breast cancer. For two of the arms of the trial, doxorubicin and cyclophosphamide followed by paclitaxel (AC-T) and doxorubicin and cyclophosphamide followed by paclitaxel and trastuzumab concurrent chemotherapy-trastuzumab (AC-TH), recurrence score (RS) and HER2 mRNA expression were determined by the 21-gene assay (Oncotype DX®) (negative <10.7, equivocal 10.7 to <11.5, and positive ?11.5 log2 expression units). Cox regression was used to assess the association of HER2 expression with trastuzumab benefit in preventing distant recurrence.Median follow-up was 7.4 years. Of 1,940 total patients, 901 had consent and sufficient tissue. HER2 by reverse transcriptase polymerase chain reaction (RT-PCR) was negative in 130 (14 %), equivocal in 85 (9 %), and positive in 686 (76 %) patients. Concordance between HER2 assessments was 95 % for RT-PCR versus central immunohistochemistry (IHC) (>10 % positive cells?=?positive), 91 % for RT-PCR versus central fluorescence in situ hybridization (FISH) (?2.0?=?positive) and 94 % for central IHC versus central FISH. In the primary analysis, the association of HER2 expression by 21-gene assay with trastuzumab benefit was marginally nonsignificant (nonlinear p?=?0.057). In hormone receptor-positive patients (local IHC) the association was significant (p?=?0.002). The association was nonlinear with the greatest estimated benefit at lower and higher HER2 expression levels.Concordance among HER2 assessments by central IHC, FISH, and RT-PCR were similar and high. Association of HER2 mRNA expression with trastuzumab benefit as measured by time to distant recurrence was nonsignificant. A consistent benefit of trastuzumab irrespective of mHER2 levels was observed in patients with either IHC-positive or FISH-positive tumors. Trend for benefit was observed also for the small groups of patients with negative results by any or all of the central assays.Clinicaltrials.gov NCT00005970 . Registered 5 July 2000.

SUBMITTER: Perez EA 

PROVIDER: S-EPMC4589954 | biostudies-literature | 2015 Oct

REPOSITORIES: biostudies-literature

altmetric image

Publications

The relationship between quantitative human epidermal growth factor receptor 2 gene expression by the 21-gene reverse transcriptase polymerase chain reaction assay and adjuvant trastuzumab benefit in Alliance N9831.

Perez Edith A EA   Baehner Frederick L FL   Butler Steven M SM   Thompson E Aubrey EA   Dueck Amylou C AC   Jamshidian Farid F   Cherbavaz Diana D   Yoshizawa Carl C   Shak Steven S   Kaufman Peter A PA   Davidson Nancy E NE   Gralow Julie J   Asmann Yan W YW   Ballman Karla V KV  

Breast cancer research : BCR 20151001 1


<h4>Introduction</h4>The N9831 trial demonstrated the efficacy of adjuvant trastuzumab for patients with human epidermal growth factor receptor 2 (HER2) locally positive tumors by protein or gene analysis. We used the 21-gene assay to examine the association of quantitative HER2 messenger RNA (mRNA) gene expression and benefit from trastuzumab.<h4>Methods</h4>N9831 tested the addition of trastuzumab to chemotherapy in stage I-III HER2-positive breast cancer. For two of the arms of the trial, dox  ...[more]

Similar Datasets

| S-EPMC7674704 | biostudies-literature
| S-EPMC4980566 | biostudies-literature
| S-EPMC5581215 | biostudies-literature
| S-EPMC4453859 | biostudies-literature
| S-EPMC3260130 | biostudies-literature
| S-EPMC5769872 | biostudies-literature
| S-EPMC7686244 | biostudies-literature
| S-EPMC3805021 | biostudies-literature
| S-EPMC3731983 | biostudies-literature
| S-EPMC2954132 | biostudies-literature