Analysis of Breast-Conserving Surgery Plus Whole-Breast Irradiation Versus Mastectomy

Study Overview
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Brief Summary
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This is a retrospective propensity score-matched analysis of a large institutional cohort of patients in order to compare long-term outcomes and clinicopathologic characteristics between patients treated with breast conserving surgery or mastectomy for breast cancer.

Detailed Description
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The aim of the study is to compare long-term outcomes and clinicopathologic characteristics between patients treated with breast conserving surgery + whole breast irradiation or mastectomy for breast cancer. Recent observations regarding long-term outcomes among patients with early-stage breast cancer who underwent breast-conserving surgery plus whole-breast irradiation or mastectomy are from a small number of registry-based studies. Therefore, these findings may overestimate differences in survival between the two groups, compared with randomized controlled trials conducted in the 1980s. This study performed a propensity score-matched analysis in a cohort of 9710 patients aged <70 years who underwent breast conserving surgery + whole breast irradiation or mastectomy without external radiotherapy for a first primary breast cancer (pT1-2, N0-3a) at the European Institute of Oncology between 2000 and 2008. Patients were matched by propensity score.

Official Title
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A Propensity Score-Matched Analysis of Breast-Conserving Surgery Plus Whole-Breast Irradiation Versus Mastectomy in Breast Cancer

Conditions
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Breast Cancer

Intervention / Treatment
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* Procedure: Breast-conserving surgery
* Procedure: Mastectomy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: First primary breast cancer pT1-2 pN0-3a Surgery performed at European Institute of Oncology between 2000 and 2008 Exclusion Criteria: pT>=3 Neoadjuvant treatment Presence of metastatic breast disease at the time of admission or within 3 months
Sexes Eligible for Study
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Female

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Breast-conserving surgery<br>Patients who underwent breast-conserving surgery plus whole-breast irradiation | Procedure: Breast-conserving surgery<br>* Breast conserving surgery plus whole breast irradiation<br>|
| Mastectomy<br>Patients who underwent mastectomy | Procedure: Mastectomy<br>* Breast mastectomy<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cumulative incidence of ipsilateral breast tumor recurrence | Incidence of ipsilateral breast tumor recurrence in breast conserving surgery group compared to mastectomy group | 10 years | 
| Cumulative incidence of axillary lymph node recurrence | cumulative incidence of axillary lymph node recurrence in breast conserving surgery group compared to mastectomy group | 10 years | 
| Cumulative incidence of contralateral breast cancer | Cumulative incidence of contralateral breast cancer in breast conserving surgery group compared to mastectomy group | 10 years | 
| Rate of distant metastasis | Incidence of distant metastasis in breast conserving surgery group compared to mastectomy group | 10 years | 
| Cumulative incidence of breast cancer specific survival | Cumulative incidence of breast cancer specific survival in breast conserving surgery group compared to mastectomy group | 10 years | 
| Rate of overall survival | Incidence of survival in breast conserving surgery group compared to mastectomy group | 10 years |