Tissue Reinforcement for Breast Reconstruction (TRBR) Pivotal Clinical Study (REDEFINE)

Inclusion Criteria: 1. Female subjects ≥ 22 years of age. 2. First-time breast reconstruction post-mastectomy for target breast(s). 3. Scheduled to undergo unilateral or bilateral mastectomy with immediate, two-stage, implant-based, subpectoral or prepectoral breast reconstruction after mastectomy. 4. Mastectomy performed to address breast cancer or for cancer prophylaxis. 5. An informed consent form is signed by Subject or Legally Authorized Representative (LAR). 6. Subject is capable of following protocol procedures and complying with follow-up visit requirements Exclusion Criteria: Baseline Exclusion Criteria 1. Subject has had a revision(s) in the target breast(s) following complications of breast augmentation, mastopexy (breast lift), or breast reduction. 2. Subject has undergone previous radiation therapy to the reconstruction site or chest wall. 3. Subject has had chemotherapy within 3 weeks prior to the index procedure. 4. Subject has been treated for a systemic infection or local infection at the surgical site within 30 days prior to index procedure. 5. Subject has a current or previous diagnosis of Methicillin-resistant Staphylococcus aureus (MRSA). 6. Subject has a BMI \> 35. 7. Subject has a known diagnosis of diabetes with a HbA1c \> 7.0mmol/L within 30 days of the Index procedure (i.e., TE placement). 8. Subject was a current or former tobacco/nicotine user, within 90 days prior to Index Surgery (i.e., TE placement). 9. Subject is currently taking medication (e.g., systemic steroid), which in the investigator's opinion, may increase the risk of local complications of breast reconstruction. 10. Subject has other medical, social, or psychological conditions which could interfere with provision of informed consent, completion of tests, therapy, or follow-up. 11. Subject is currently participating in or planning to participate in another investigational drug, biologic or medical device study that may interfere with compliance of TBR 22-07 study requirements or may confound TBR 22-07 study data/outcomes. 12. Subject requires a surgical technique requiring flap (autologous tissue). 13. Subject is pregnant or lactating at the time of the index procedure (i.e., TE placement) or is planning to become pregnant prior to the Exchange procedure. Intraoperative Index Procedure Exclusion 14. Based on investigator's opinion, subject has unsuitable tissue integrity for immediate 2-stage breast reconstruction or is no longer a candidate to receive the TRBR Device (will be recorded as a screen failure). 15. Subject receives an Acellular Dermal Matrix (ADM) or mesh that is not the TRBR Device in the target breast(s)