1. Acellular dermal matrix in tissue expander-based breast reconstruction predicts increased infection and seroma in a multivariate regression model Eric D Wang BS, Steven T Lanier BA, BS, Taygan Yilmaz MPH, Brett T Phillips MD, Balvant P Arora MD, Steven M Katz MD, Sami U Khan MD, Alexander B Dagum MD, Duc T Bui, MD Stony Brook University Medical Center Division of Plastic and Reconstructive Surgery American Society of Plastic Surgeons: Plastic Surgery 2010 Toronto, ON

2. Disclosures: nothing to disclose

3. Breast reconstruction with tissue expanders Acellular Dermal Matrix (ADM) is a relatively recent adjunct to implant-based breast reconstruction Suggested benefits include: Prevention of implant exposure Improved control of the inframammary fold Improved aesthetics, with a more natural ptosis Improved expansion dynamics

4. Reported complication rates with ADM Non-ADM complications ADM complications P-value (2-tail) Antony et al. 201012.4%23.6%<0.05* Lanier et al. 201012.0%28.9%0.02* Chun et al. 20102.1%8.9%0.03* Nahabedian 20095.85%5% ★ Sbitany et al. 200914%18%0.79 Preminger et al. 20086.7%15.6%0.18 Non-comparative case series (20 publications, n= 5 – 67) Range (0-20%) ★ * Denotes statistical significance ★ No statistical comparison was made

5. Research question What are the complication risks associated with acellular dermal matrix use?

6. Methods Design: retrospective database review Setting: postmastectomy TE/I breast reconstructions at a single center between 2004 and 2009 Sample size ADM: 105 breasts (77 patients) non-ADM: 161 breasts (105 patients) Statistical analysis Descriptive statistics, Student’s t-, and Fisher’s Exact Multivariate logistic regression

7. Model parameters: predictor variables Age BMI Tobacco Neoadjuvant chemotherapy and radiation Postop chemotherapy and radiation ADM use Indication for mastectomy Time between stages JP drain duration Mastectomy specimen weight Tissue expander size Intraoperative fill volume

8. Model parameters: outcome variables Infection Mastectomy skin necrosis Seroma Hematoma Capsular contracture Expander explantation due to infection Reoperation due to complications

9. Results: baseline patient characteristics Non-ADM (n = 161) ADM (n = 105) P value (2-tailed) mean age at time of stage I 48.651.20.04* mean BMI 24.128.1< 0.001* mean breast tissue removed 601g891g< 0.001* tobacco use 34 (21.1%)16 (15.2%)0.26 pre-stage I chemotherapy 31 (19.3%)18 (17.1%)0.75 post-stage I chemotherapy 56 (34.8%)38 (36.2%)0.90 pre-stage I radiation 7 (4.4%)4 (3.8%)1 post-stage I radiation 11 (6.6%)4 (3.8%)0.42 number risk-reducing 44 (27.3%)29 (27.6%)1 * Denotes statistical significance

10. Results: univariate analysis * Denotes statistical significance

11. Results: multivariate regression model Significant independent predictors of infection: Odds Ratiop - value95% CI ADM use12.860.0441.067 – 155.1 decreased age0.860.0240.756 – 0.981 pre-op radiation3120.0391.331 – 73723 time to exchange1.0130.0071.003 – 1.023

12. Results: multivariate regression model Significant independent predictors of seroma formation: Odds Ratiop - value95% CI ADM use7.3770.0081.700 – 32.02 total fill volume1.0060.0301.001 – 1.012

13. Conclusions Acellular dermal matrix is associated with increased risk of infection and seroma, independent of other factors influencing operative outcome Proposed benefits of ADM must be weighed against the risk of increased complications

14. Minimizing future complications Understanding the etiology of complications Refinement of surgical and postoperative care protocols to avoid complications with ADM Utilizing risk factors to guide patient selection and preoperative planning for breast reconstruction

15. References and Contact 1.Preminger BA, McCarthy CM, Hu QY, Mehrara BJ, Disa JJ. The influence of AlloDerm on expander dynamics and complications in the setting of immediate tissue expander/implant reconstruction: a matched-cohort study. Ann Plast Surg 60; 510-513; 2008. 2.Chun YS, Verma K, Rosen H, Lipsitz S, Morris D, Kenney P, Eriksson E. Implant-based breast reconstruction using acellular dermal matrix and the risk of postoperative complications. Plast Reconstr Surg 125; 429-436; 2010. 3.Lanier ST, Wang ED, Chen JJ, Arora BP, Katz SM, Khan SU, Dagum AB, Bui DT. The effect of acellular dermal matrix use on complication rates in tissue expander/implant breast reconstruction. Ann Plast Surg 64; 674-678; 2010. 4.Antony AK, McCarthy CM, Cordeiro PG, Mehrara BJ, Teo EH, Arriaga AF, Disa JJ. Acellular human dermis implantation in 153 immediate two-stage tissue expander breast reconstructions: determining the incidence and significant predictors of complications. Plast Reconstr Surg 125; 1606-1614; 2010. 5.Nahabedian MY. AlloDerm performance in the setting of prosthetic breast surgery, infection, and irradiation. Plast Reconstr Surg 124: 1743; 2009. 6.Sbitany H, Sandeen SN, Amalfi AN, Davenport MS, Langstein HN. Acellular dermis-assisted prosthetic breast reconstruction vs complete submuscular coverage: a head-to-head comparison of outcomes. Plast Reconstr Surg 124: 1735, 2009. Contact: Duc T. Bui, MD Stony Brook University Medical Center Division of Plastic and Reconstructive Surgery HSC T19-060 Stony Brook, NY 11794