| Title |
Assessment of Ki67 expression for breast cancer subtype classification and prognosis in the Nurses’ Health Study
|
|---|---|
| Published in |
Breast Cancer Research and Treatment, August 2017
|
| DOI | 10.1007/s10549-017-4421-3 |
| Pubmed ID | |
| Authors |
Megan A. Healey, Kelly A. Hirko, Andrew H. Beck, Laura C. Collins, Stuart J. Schnitt, A. Heather Eliassen, Michelle D. Holmes, Rulla M. Tamimi, Aditi Hazra |
| Abstract |
Ki67 is a proliferation marker commonly assessed by immunohistochemistry in breast cancer, and it has been proposed as a clinical marker for subtype classification, prognosis, and prediction of therapeutic response. However, the clinical utility of Ki67 is limited by the lack of consensus on the optimal cut point for each application. We assessed Ki67 by immunohistochemistry using Definiens digital image analysis (DIA) in 2653 cases of incident invasive breast cancer diagnosed in the Nurses' Health Study from 1976 to 2006. Ki67 was scored as continuous percentage of positive tumor cells, and dichotomized at various cut points. Multivariable hazard ratios (HR) and 95% confidence intervals (CI) were calculated using Cox regression models for distant recurrence, breast cancer-specific mortality and overall mortality in relation to luminal subtypes defined with various Ki67 cut points, adjusting for breast cancer prognostic factors, clinico-pathologic features and treatment. DIA was highly correlated with manual scoring of Ki67 (Spearman correlation ρ = 0.86). Mean Ki67 score was higher in grade-defined luminal B (12.6%), HER2-enriched (17.9%) and basal-like (20.6%) subtypes compared to luminal A (8.9%). In multivariable-adjusted models, luminal B tumors had higher breast cancer-specific mortality compared to luminal A cancer classified using various cut points for Ki67 positivity including the 14% cut point routinely reported in the literature (HR 1.38, 95% CI 1.11-1.72, p = 0.004). There was no significant difference in clinical outcomes for ER- tumors according to Ki67 positivity defined at various cut points. Assessment of Ki67 in breast tumors by DIA was a robust and quantitative method. Results from this large prospective cohort study provide support for the clinical relevance of using Ki67 at the 14% cut point for luminal subtype classification and breast cancer prognosis. |
X Demographics
The data shown below were collected from the profile of 1 X user who shared this research output. Click here to find out more about how the information was compiled.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| United States | 1 | 100% |
Demographic breakdown
| Type | Count | As % |
|---|---|---|
| Members of the public | 1 | 100% |
Mendeley readers
The data shown below were compiled from readership statistics for 52 Mendeley readers of this research output. Click here to see the associated Mendeley record.
Geographical breakdown
| Country | Count | As % |
|---|---|---|
| Unknown | 52 | 100% |
Demographic breakdown
| Readers by professional status | Count | As % |
|---|---|---|
| Student > Master | 6 | 12% |
| Student > Bachelor | 4 | 8% |
| Student > Ph. D. Student | 4 | 8% |
| Other | 3 | 6% |
| Professor > Associate Professor | 3 | 6% |
| Other | 5 | 10% |
| Unknown | 27 | 52% |
| Readers by discipline | Count | As % |
|---|---|---|
| Medicine and Dentistry | 15 | 29% |
| Nursing and Health Professions | 5 | 10% |
| Unspecified | 1 | 2% |
| Biochemistry, Genetics and Molecular Biology | 1 | 2% |
| Agricultural and Biological Sciences | 1 | 2% |
| Other | 1 | 2% |
| Unknown | 28 | 54% |
Attention Score in Context
This research output has an Altmetric Attention Score of 1. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 11 August 2017.
All research outputs
#15,475,586
of 22,997,544 outputs
Outputs from Breast Cancer Research and Treatment
#3,318
of 4,677 outputs
Outputs of similar age
#199,359
of 317,853 outputs
Outputs of similar age from Breast Cancer Research and Treatment
#53
of 82 outputs
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