Comparative Analysis of Two Animal-derived ADMs in Irradiated Implant-based Reconstruction

Study Overview
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Brief Summary
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The goal of this retrospective observational trial is to compare two different devices, used in implant-based breast reconstruction, called acellular dermal matrices, which are a sort of collagen patch that integrates with the tissues of the patient and helps in contrasting the collateral effects of radiotherapy (capsular contracture, implant loss) The main questions the study aims to answer are: is one of the two matrices better than the other? (better results with fewer complications) is there a group of patients who benefit more than another from the use of this type of devices? is there an adm which works better in one specific subgroup of patients? Participants have undergone mastectomy, radiotherapy and implant reconstruction with the aid of two different kinds of acellular dermal matrices. Researchers will compare patients who receive the porcine-derived adm and the patients who receive bovine-derived adm to see if there is a difference in terms of capsular contracture reduction, aestethic result and complications.

Detailed Description
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Radiotherapy is highly effective in breast cancer treatment, yet it impairs satisfactory implant-based reconstruction, due to high rates of capsular contracture and implant loss. This said, a fervent investigtion exists upon solutions that can make implant-based reconstruction safer and aesthetically satisfying, including the use of acellular dermal matrices. We retrospectively want to analyze our ADM-assisted post-RT implant-based breast reconstructions comparing two different matrices (porcine and bovine), when autologous reconstruction was contraindicated, to assess eventual differences in efficacy and risk profile of the devices. We want to further stratify the population in 4 groups based on clinical presentation to assess if there was a group where ADMs proves to perform better (Group A - previous quadrantectomy, Group B - previous mastectomy and expander reconstruction, Group C - previous mastectomy and implant reconstruction, Group D - prior quadrantectomy followed by mastectomy and implant reconstruction).

Official Title
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Comparative Study of the Efficacy and Risk Profile of Two Animal-derived Acellular Dermal Matrices in Patients Undergoing Mastectomy, Radiotherapy and Implant-based Reconstruction

Conditions
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Breast Implant; Complications, Breast Implant Infection, Implant Capsular Contracture, Breast Seroma, Breast Implant Protrusion, Breast Cancer

Intervention / Treatment
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* Device: acellular dermal matrix implant for breast reconstruction


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: at least 6 months follow up breast reconstruction with implant + acellular dermal matrix after mastectomy and radiotherapy Exclusion Criteria: mastectomy flap <1 cm autoimmune disease prolonged use of corticosteroids
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 |
| --- | --- |
| POST QUART NATIVE<br>Native adm used in the setting of mastectomy and implant reconstruction after QUART | Device: acellular dermal matrix implant for breast reconstruction<br>* acellular dermal matrix implant in implant-based breast reconstruction in patients receiving radiotherapy<br>|
| POST QUART VERITAS<br>Veritas adm used in the setting of mastectomy and implant reconstruction after QUART | Device: acellular dermal matrix implant for breast reconstruction<br>* acellular dermal matrix implant in implant-based breast reconstruction in patients receiving radiotherapy<br>|
| POST EXPANDER NATIVE<br>Native adm used in the setting of expander removal and implant positioning after mastectomy + RT | Device: acellular dermal matrix implant for breast reconstruction<br>* acellular dermal matrix implant in implant-based breast reconstruction in patients receiving radiotherapy<br>|
| POST EXPANDER VERITAS<br>Veritas adm used in the setting of expander removal and implant positioning after mastectomy + RT | Device: acellular dermal matrix implant for breast reconstruction<br>* acellular dermal matrix implant in implant-based breast reconstruction in patients receiving radiotherapy<br>|
| IMPLANT EXCHANGE NATIVE<br>Native adm used in the setting of implant exchange after mastectomy + RT | Device: acellular dermal matrix implant for breast reconstruction<br>* acellular dermal matrix implant in implant-based breast reconstruction in patients receiving radiotherapy<br>|
| IMPLANT EXCHANGE VERITAS<br>Veritas adm used in the setting of implant exchange after mastectomy + RT | Device: acellular dermal matrix implant for breast reconstruction<br>* acellular dermal matrix implant in implant-based breast reconstruction in patients receiving radiotherapy<br>|
| IMPANT EXCHANGE AFTER QUART NATIVE<br>Native adm used in the setting of implant exchange after QUART+ Mastectomy and implant reconstruction | Device: acellular dermal matrix implant for breast reconstruction<br>* acellular dermal matrix implant in implant-based breast reconstruction in patients receiving radiotherapy<br>|
| IMPLANT EXCHANGE AFTER QUART VERITAS<br>Veritas adm used in the setting of implant exchange after QUART+ Mastectomy and implant reconstruction | Device: acellular dermal matrix implant for breast reconstruction<br>* acellular dermal matrix implant in implant-based breast reconstruction in patients receiving radiotherapy<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| ADM efficacy and risk profile comparison | Does one dermal matrix perform better than the other in terms of efficacy and complication rates? | 60 months | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Best clinical setting for ADM use | Is there a subgroup of patient where the use of ADM proves more beneficial than others? | 60 months | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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implant-based, breast reconstruction, adm, radiation therapy, irradiated breast