Spatial Location of Breast Cancer Local Recurrence After Mastectomy

Study Overview
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Brief Summary
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Rationale:To improve the definition of the target volume for radiotherapy of the chestwall after different types of mastectomy, the exact localization of regions at risk for a local recurrence should be known. However, there are currently insufficient data in literature showing where local recurrences occur after different types of mastectomy. Objective: The primary objective of the proposed study is to determine whether the spatial, location of a breast cancer recurrence after mastectomy, differs for different types of mastectomy. Study design: Retrospective study evaluating spatial location and site of recurrences after mastectomy. Study population: The investigators aim to include all breast cancer patients treated with mastectomy in the Netherlands between 2003- 2008, and known to have experienced a local recurrence as the first site of failure. Primary endpoint: Spatial location of local recurrence (e.g., primary tumour bed, scar, skin, subcutaneous, nipple, areola, pectoral muscles).

Detailed Description
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Rationale:To improve the definition of the target volume for radiotherapy of the chestwall after different types of mastectomy, the exact localization of regions at risk for a local recurrence should be known. However, there are currently insufficient data in literature showing where local recurrences occur after different types of mastectomy. Objective: The primary objective of the proposed study is to determine whether the spatial, location of a breast cancer recurrence after mastectomy, differs for different types of mastectomy. Secondary objectives are to assess whether tumour characteristics (e.g., molecular subtypes, lymphangio/lymphovascular invasion) and treatment-related factors (e.g., PMRTwith or without bolus, radiation volumes, doses) influence the site of recurrence and spatial location. Study design: Retrospective study evaluating spatial location and site of recurrences after mastectomy. Study population: The investigators aim to include all breast cancer patients treated with mastectomy in the Netherlands between 2003- 2008, and known to have experienced a local recurrence as the first site of failure. Primary endpoint: Primary endpoint: Spatial location of local recurrence (e.g., primary tumour bed, scar, skin, subcutaneous, nipple, areola, pectoral muscles). Other study parameters: First descriptive statistics will be performed to investigate whether there is a relation between the localization of the recurrence and the type of mastectomy: modified radical mastectomy (MRM), skin-sparing mastectomy (SSM), nipple sparing mastectomy (NSM).

Official Title
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Spatial Location of Breast Cancer Local Recurrence After Mastectomy: the Secret Study, a Retrospective Analysis.

Conditions
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Breast Cancer

Intervention / Treatment
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* Procedure: Mastectomy


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Age 18 years and more at the time of breast cancer diagnosis. Proven histology of first invasive breast cancer Mastectomy as a surgical procedure for breast cancer (regardless of perioperative treatment). Having a local recurrence, as primary event reast cancer diagnosis in the period 2003-2008. Exclusion Criteria: Non-epithelial histology. Primary metastatic breast cancer. Mastectomy for breast cancer recurrence after earlier breast conserving therapy. Synchronous breast cancer.

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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Female

Study Plan
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How is the study designed?
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Arms and Interventions

| Intervention/Treatment |
| --- |
|Procedure: Mastectomy|Mastectomy as a surgical procedure for breast cancer (regardless of perioperative treatment).|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Spatial localisation of local recurrences | The primary objective of the proposed study is to determine whether the spatial, location of a breast cancer recurrence after mastectomy, differs for different types of mastectomy. | Up to 15 years after mastectomy | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Influence of tumour characteristics on the site of recurrence and spatial location. | Anaysis to assess whether tumour characteristics (e.g., molecular subtypes, lymphangio/lymphovascular invasion) influence the site of recurrence and spatial location. | Up to 15 years after mastectomy | 
| Influence of treatment-related factors on the site of recurrence and spatial location. | Anaysis to assess whether treatment-related factors (e.g., PMRT with or without bolus, radiation volumes, doses) influence the site of recurrence and spatial location. | Up to 15 years after mastectomy | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Mastectomy