This is a prospective, histologic analysis of biopsied tissue obtained from participants who have undergone a pre-pectoral breast reconstruction or augmentation surgery with expander placement and AlloMend® Acellular Dermal Matrix.

AlloMend® Acellular Dermal Matrix graft incorporation with surrounding native soft tissue using histological assays characterizing host cell infiltration, neovascularization, inflammation, and host replacement of ADM collagen will be studied.

The purpose of this study is to evaluate the incorporation of AlloMend® Acellular Dermal Matrix with native surrounding tissue by obtaining up to three, 1 cm diameter biopsies per breast. The samples will then be transported to AlloSource Research and Development Labs for slide preparation and histologic analysis.

This study will be performed at one (1) clinical center in the United States.

Inclusion Criteria:

• ≥18 years of age;
• AlloMend® Acellular Dermal Matrix used during the initial prepectoral placement of tissue expanders for breast reconstruction;
• Is scheduled or will be scheduled for a procedure to exchange the tissue expander for permanent breast implant;
• Can understand the requirements of the study, has provided written, informed consent, and to comply with the study protocol.

Exclusion Criteria:

• Mentally compromised (e.g., being currently treated for a psychiatric disorder, senile dementia, Alzheimer's disease) in a manner that would compromise his or her ability to consent to participate in the clinical study;
• Subjects who, in the opinion of the investigator, would not be able or willing to comply with the protocol.

Adults 18 years of age or greater who have undergone a pre-pectoral placement of tissue expanders for breast reconstruction and will have a histological evaluation of the AlloMend® Acellular Dermal Matrix and native tissue at time of permanent breast implantation