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Woods R, Yerushalmi R, Speers C, Tydesley S, Gelmon K. P5-14-17: Stage IV at Presentation – Are HER2 Positive Tumors Overrepresented? Cancer Res 2011. [DOI: 10.1158/0008-5472.sabcs11-p5-14-17] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: A minority of patients are diagnosed with Stage IV breast cancer at presentation. Recent studies (Dawood 2010) have suggested a better outcome for de novo vs. recurrent Stage IV but they did not account for the variation of molecular subtype. We questioned whether HER2 overexpressing tumors were over-represented in de novo Stage IV disease, and whether this impacted on survival compared to other subtypes. Further, if different subtypes are more likely to present with metastatic disease, then this factor may need to be considered when developing guidelines for staging. With such considerations in mind, the purpose of this study was to determine the breast cancer subtypes according to stage. The main hypothesis was that HER2 positive tumors would be more prevalent in stage IV presentations. Methods: Using the Breast Cancer Outcomes Unit database from the BC Cancer Agency (BCCA), patients referred to the BCCA with a new diagnosis of breast cancer between 2005 and 2010 were selected. Patients with a previous or synchronous contralateral breast cancer, male cases, and patients with referrals for reasons other than new disease were excluded. Four subtypes according to available markers were defined: ER+/HER2−, ER+/HER2+, ER-/HER2+, and ER-/HER2−.
Results: Using these criteria, 485 cases of de novo stage IV disease and 10,723 stages I — III cases were extracted. After excluding cases with missing data, our final cohort consisted of 10,186 stage I-III cases and 425 stage IV cases. Distribution by subtype is presented in the Table below.
Assessment of other patient characteristics for the group of Stage IV de novo patients revealed that age (younger for HER+ subgroups), site of metastases (more visceral vs. non- visceral for ER-/HER2+ and ER-/HER2−) and type of systemic therapy (chemotherapy (CT), hormone therapy (HT), trastuzumab (T) or not) were significant. Surgery rates for both mastectomy and breast-conserving surgery were similar for all subtypes. The ER-/HER2− subtype had the worst overall survival (p < 0.001).
Conclusion: Young age and HER2 overexpression is more common in stage IV de novo presentations (26.6% of stage IV tumors were HER2+ vs. only 16% of stage I-III tumors). This data may be important in considering routine staging guidelines at diagnosis to ensure correct diagnosis and treatment recommendations.
Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-14-17.
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Affiliation(s)
- R Woods
- 1BC Cancer Agency, Vancouver, BC, Canada
| | | | - C Speers
- 1BC Cancer Agency, Vancouver, BC, Canada
| | - S Tydesley
- 1BC Cancer Agency, Vancouver, BC, Canada
| | - K Gelmon
- 1BC Cancer Agency, Vancouver, BC, Canada
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