Here is the capsule summary of the data from this study:
Capsule Summary
CCO Independent Conference Coverage of the 2009 Annual Meeting of the AACR-CTRC San Antonio Breast Cancer Symposium*
*CCO is an independent medical education company that provides state-of-the-art medical information to healthcare professionals through conference coverage and other educational programs.
HER2 Positivity a Risk Factor for Recurrence in ER-Positive Early-Stage Breast Cancer
Posting Date: December 15, 2009
- Analysis of prognostic factors in retrospective cohort dataset
Summary of Key Conclusions
- HER2, estrogen receptor (ER)–positive patients with early-stage breast cancer at significantly increased risk of recurrent disease within 2.5 years after diagnosis
- Peak in annual recurrence rate at 2 years in HER2-positive group
- AIs reduce the risk of recurrence in HER2-positive patients
- Trastuzumab should be considered for ER-positive, HER2-positive patients given that inhibition of growth factor signaling may increase response to endocrine therapy
Background
- AIs provide survival benefit in ER-positive early-stage breast cancer and reduce risk of recurrence
- Optimal timing for initiation of AI therapy in relation to tamoxifen therapy not well defined
- Identification of prognostic markers would be helpful in selection of patients for treatment with AIs
- Current study sought to determine whether progesterone receptor (PgR) status or HER2 status predictive for recurrence in ER-positive early breast cancer
Summary of Study Design
- Analysis of ER, PgR, and HER2 expression in retrospective cohort of women with symptomatic early-stage breast cancer diagnosed between 1980 and 2002 and treated with adjuvant tamoxifen
- Definition of recurrence
- Invasive malignancy on histopathology at any site or
- High index of suspicion upon radiologic investigation
- Primary study endpoint
- Kaplan-Meier analysis of DFS: 2.5 years and 5.0 years
- Time-dependent Cox regression analysis assessed using term ≤ 2.5 years
- HR for recurrence rate per year by panechnikov smoothing function; bandwidth of 6 months
- Multivariate time-dependent analysis
- Adjusted for HER2 status, tumor size, grade, nodal status, PgR status, and HER2 status associated with DFS at time from diagnosis
Baseline Characteristics
- Patient and disease characteristics at baseline
Characteristic, %
| Patients |
---|
Age at diagnosis, yrs
| |
| 16.2 |
| 20.6 |
| 33.6 |
| 29.4 |
| 0.2 |
Tumor size, cm
| |
| 38.3 |
| 50.7 |
| 5.5 |
| 5.5 |
Grade
| |
| 24.6 |
| 48.0 |
| 24.6 |
| 2.7 |
Number of lymph nodes
| |
| 48.0 |
| 26.6 |
| 17,2 |
| 8,2 |
PgR status
| |
| 60.0 |
| 36.6 |
| 3.5 |
HER2 status
| |
| 12.7 |
| 86.1 |
| 1.2 |
Radiotherapy
| 28.1 |
Chemotherapy
| 25.4 |
Main Findings
- Tumors confirmed as ER positive (n = 402)
- Median follow-up: 6.1 years
- Median age of cohort: 63 years
- PgR positive, 60%
- HER2 positive, 12.7%
- HER2-positive status associated with lower DFS rates at 2.5 and 5.0 years
Characteristic, %
| DFS at 2.5 Yrs | DFS at 5.0 Yrs |
---|
Overall
| 87.7 (86.1-89.3) | 80.7 (78.7-82.7) |
| | |
| 91.7 (89.9-93.5) | 86.0 (83.7-88.3) |
| 80.7 (77.4-84.0) | 71.8 (68.0-75.6) |
| | |
| 74.5 (68.4-80.6) | 70.5 (64.1-76.9) |
| 90.1 (88.5-91.7) | 82.6 (80.5-84.7) |
- Univariate analysis of factors significantly associated with DFS
- Tumor size: P < .001
- Grade: P < .001
- Nodal status: P < .001
- PgR status: P = .002
- Multivariate time-dependent analysis between HER2 status and time dependant term
- ≤ 2.5 years, HR: 2.54 (95% CI: 1.21-5.32)
- > 2.5 years, HR: 0.33 (95% CI: 0.10-1.11; P = .004)
- Peak in annual recurrence rate at 2 years in HER2-positive group
Reference
Mansell J, Tovey S, Angerson WJ, Wilson CR, Doughty JC
. The tnfluence of HER2 status on the recurrence pattern in oestrogen receptor positive (ER+) early breast cancer (EBC). Program and abstracts of the 32nd Annual San Antonio Breast Cancer Symposium; December 9-13, 2009; San Antonio, Texas. Abstract 4045.