Summary: Adipose-derived stem cell therapy offers plastic surgeons a novel treatment alternative for conditions with few therapeutic options. Adipose-derived stem cells are a promising treatment because of their broad differentiation potential, capacity for self-renewal, and ease of isolation. Over the past decade, plastic surgeons have attempted to harness adipose-derived stem cells’ unique cellular characteristics to improve the survival of traditional fat grafting procedures, a process known as cell-assisted lipotransfer. However, the full implications of cell-assisted lipotransfer in clinical practice remain incompletely understood, stressing the urgent need to assess the scientific evidence supporting adipose-derived stem cell–based interventions. Furthermore, with the strict regulatory climate surrounding tissue explantation therapies, reviewing the safety and efficacy of these treatments will clarify their regulatory viability moving forward. In this report, the authors provide a comprehensive, up-to-date appraisal of best evidence-based practices supporting adipose-derived stem cell–derived therapies, highlighting the known mechanisms behind current clinical applications in tissue engineering and regenerative medicine specific to plastic and reconstructive surgery. The authors outline best practices for the harvest and isolation of adipose-derived stem cells and discuss why procedure standardization will elucidate the scientific bases for their broad use. Finally, the authors discuss challenges posed by U.S. Food and Drug Administration oversight of these cell-based therapies and examine the role of adipose-derived stem cell–based applications in the future of plastic surgery.
Autologous Fat Grafting Does Not Increase Risk of Oncologic Recurrence in the Reconstructed Breast
Summary: Breast implant–associated anaplastic large cell lymphoma (BIA-ALCL) is an emerging and highly treatable cancer of the immune system that can form around textured-surface breast implants. Although the underlying cause has yet to be elucidated, an emerging theme—linking pathogenesis to a chronic inflammatory state—continues to dominate the current literature. Specifically, the combination of increasing mutation burden and chronic inflammation leads to aberrant T-cell clonal expansion. However, the impetus remains largely unknown. Proposed mechanisms include a lipopolysaccharide endotoxin response, oncogenic transformation related to viral infection, associated trauma to the breast pocket, particulate matter digestion by capsular macrophages, chronic allergic inflammation, and genetic susceptibility. The Janus kinase–signal transducer and activator of transcription 3 (JAK-STAT3) pathway is a major signaling pathway that regulates a variety of intracellular growth and survival processes. Constitutive activation of JAK-STAT3 has been implicated in several malignancies, including lymphomas, and has recently been identified as a potential key mediator in BIA-ALCL. The purpose of this article is to review the cellular and molecular mechanisms of BIA-ALCL with a focus on the role of oncogenic JAK-STAT3 signaling in BIA-ALCL tumorigenesis and progression. Selected experimental work from the authors’ group on aberrant JAK-STAT3 signaling in BIA-ALCL is also included. The authors discuss how an inflammatory microenvironment may facilitate malignant transformation through the JAK-STAT3 pathway—highlighting its potential mechanistic role. The authors’ hope is that further investigation of this signaling pathway will reveal avenues for using JAK-STAT3 signaling as a prognostic indicator and novel therapeutic target in the case of advanced disease.
Reply: Fat Graft Enrichment Strategies: A Systematic Review
Background: Autologous fat grafting is a dynamic modality used in plastic surgery as an adjunct to improve functional and aesthetic form. However, current practices in fat grafting for soft-tissue augmentation are plagued by tremendous variability in long-term graft retention, resulting in suboptimal outcomes and repetitive procedures. This systematic review identifies and critically appraises the evidence for various enrichment strategies that can be used to augment and improve the viability of fat grafts. Methods: A comprehensive literature search of the Medline and PubMed databases was conducted for animal and human studies published through October of 2017 with multiple search terms related to adipose graft enrichment agents encompassing growth factors, platelet-rich plasma, adipose-derived and bone marrow stem cells, gene therapy, tissue engineering, and other strategies. Data on level of evidence, techniques, complications, and outcomes were collected. Results: A total of 1382 articles were identified, of which 147 met inclusion criteria. The majority of enrichment strategies demonstrated positive benefit for fat graft survival, particularly with growth factors and adipose-derived stem cell enrichment. Platelet-rich plasma and adipose-derived stem cells had the strongest evidence to support efficacy in human studies and may demonstrate a dose-dependent effect. Conclusions: Improved understanding of enrichment strategies contributing to fat graft survival can help to optimize safety and outcomes. Controlled clinical studies are lacking, and future studies should examine factors influencing graft survival through controlled clinical trials in order to establish safety and to obtain consistent outcomes.
Autologous Fat Grafting Does Not Increase Risk of Oncologic Recurrence in the Reconstructed Breast
Introduction Autologous fat grafting (AFG) is a popular and effective method of breast reconstruction after mastectomy; however, the oncological safety of AFG remains in question. The aim of this study was to determine whether AFG increases the risk of cancer recurrence in the reconstructed breast. Methods A matched, case-control study was conducted from 2000 to 2017 at the senior author's institution. Inclusion was limited to female patients who underwent mastectomy and breast reconstruction with or without AFG. Data were further subdivided at the breast level. χ2 analyses were used to test the association between AFG status and oncologic recurrence. A Cox proportional-hazards model was constructed to assess for possible differences in time to oncologic recurrence. The probability of recurrence was determined by Kaplan-Meier analyses and confirmed with log-rank testing. Results Overall, 428 breasts met study criteria. Of those, 116 breasts (27.1%) received AFG, whereas 312 (72.9%) did not. No differences in the rates of oncologic recurrence were found between the groups (8.2% vs 9.0%, P < 1.000). Unadjusted (hazard ratio = 1.03, confidence interval = 0.41–2.60, P < 0.957) and adjusted hazard models showed no statistically significant increase in time to oncologic recurrence when comparing AFG to non-AFG. In addition, no statistical differences in disease-free survival were found (P = 0.96 by log rank test). Conclusion Autologous fat grafting for breast reconstruction is oncologically safe and does not increase the likelihood of oncologic recurrence. Larger studies (eg, meta analyses) with longer follow-up are needed to further elucidate the long-term safety of AFG as a reconstructive adjunct.
Oncogenic Drivers of Breast Implant-Associated Anaplastic Large Cell Lymphoma
Background Health care disparities in Appalachia are well documented. However, no previous studies have examined possible differences in the utilization of breast reconstruction (BR) in Appalachia. This study aims to determine if a disparity in BR utilization exists in women from Appalachia Kentucky. Methods A retrospective, population-based cohort study was conducted from January 1, 2006, to December 31, 2015. The Kentucky Cancer Registry was queried to identify population-level data for female patients diagnosed with breast cancer and treated with mastectomy. A multivariate logistic regression model controlling for patient, disease, and treatment characteristics was constructed to predict the likelihood of BR. Results Bivariate testing showed differences (P < 0.0001) in BR utilization between Appalachian and non-Appalachian women in Kentucky (15.0% and 26.3%, respectively). Multivariate analysis showed that women from Appalachia (odds ratio, 0.54; confidence interval (95), 0.48–0.61; P < 0.0001) were less likely to undergo BR than non-Appalachian women. Interestingly, the rate of BR increased over time in both Appalachian (r = 0.115; P < 0.0001) and non-Appalachian women (r = 0.148; P < 0.0001). Conclusions Despite the benefits of BR, women from Appalachia undergo BR at lower rates and are less likely to receive BR than non-Appalachian Kentuckians. Although the rates of BR increased over time in both populations, access to comprehensive breast cancer care remains a challenge for women from Kentucky's Appalachian region.
Rural‐Urban Differences in Breast Reconstruction Utilization Following Oncologic Resection
AbstractBackgroundBreast reconstruction (BR) is the reconstructive surgical technique that focuses on restoring normal form and function to the breast following oncologic resection. The goal of this study was to determine if BR disparities exist among rural female patients in Kentucky.MethodsA retrospective (2006‐2015), population‐based cohort study was conducted on breast cancer patients (stages I‐III) treated with mastectomy with or without BR. We used 2013 Beale codes to stratify patients according to geographic status. Chi‐square tests were used to examine the association of BR along the rural‐urban continuum. A multivariate logistic regression model controlling for patient, disease, and treatment factors was used to predict BR. The likelihood of BR was reported in odds ratios (OR) using a 95% confidence interval (CI).ResultsOverall, 10,032 patients met study criteria. Of those, 2,159 (21.5%) underwent BR. The rate of BR among urban, near‐metro, and rural patients was 31.1%, 20.4%, and 13.4%, respectively (P < .001). Multivariate analysis revealed that women from near metro (OR 0.54, CI: 0.47‐0.61; P < .001) and rural areas (OR 0.36, CI: 0.31‐0.41; P < .001) were less likely to undergo BR than women from urban areas.ConclusionAlthough BR benefits are well documented, women from rural Kentucky undergo BR at lower rates and are less likely to receive BR than their urban counterparts. Efforts should seek to promote equitable access to BR for all patients, including those from rural areas.
Recruiting the Next Generation of Surgeon-Scientists in Plastic and Reconstructive Surgery: The Value of Research Fellowships