The safety of autologous fat transfer in breast cancer: lessons from stem cell biology

Autologous Fat Grafting (AFG): A Systematic Review to Evaluate Oncological Safety in Breast Cancer Patients

Background: Autologous fat grafting (AFG) has emerged as a useful technique in breast reconstruction. Utilizing a patient's own fat from areas like the abdomen or thighs, AFG serves various reconstruction needs. Nevertheless, the oncological safety of AFG in breast cancer patients has become a contentious issue. Concerns about its influence on cancer recurrence and detention have led to significant clinical debate and the need for thorough investigation. Methods: To determine the impact of autologous fat grafting (AFG) on loco-regional recurrence (LRR) in breast cancer survivors undergoing reconstruction, a comprehensive search of databases including PubMed, Medline, Web of Science, and Cochrane libraries was conducted from November 2023 through March 2024. This search adhered to the PRISMA guidelines and aimed to identify all the relevant studies on AFG in the context of breast reconstruction post cancer treatment. A meta-analysis was performed. Results: Out of the studies reviewed, 40 met the inclusion criteria, with a total patient cohort of 14,078. The analysis revealed that AFG had no significant association with increased rates of LRR. Conclusions: According to the available literature, AFG is a safe reconstructive option for breast cancer patients and does not increase the risk of loco-regional recurrence. Nevertheless, further well-structured long-term prospective studies are required, since heterogeneity of available studies is high and requires standardization.

Highly Concentrated Stabilized Hybrid Complexes of Hyaluronic Acid: Rheological and Biological Assessment of Compatibility with Adipose Tissue and Derived Stromal Cells towards Regenerative Medicine

Cells and extracts derived from adipose tissue are gaining increasing attention not only in plastic surgery and for aesthetic purposes but also in regenerative medicine. The ability of hyaluronan (HA) to support human adipose stromal cell (hASC) viability and differentiation has been investigated. However, the compatibility of adipose tissue with HA-based formulation in terms of biophysical and rheological properties has not been fully addressed, although it is a key feature for tissue integration and in vivo performance. In this study, the biophysical and biochemical properties of highly concentrated (45 mg/mL) high/low-molecular-weight HA hybrid cooperative complex were assessed with a further focus on the potential application in adipose tissue augmentation/regeneration. Specifically, HA hybrid complex rheological behavior was observed in combination with different adipose tissue ratios, and hyaluronidase-catalyzed degradation was compared to that of a high-molecular-weight HA (HHA). Moreover, the HA hybrid complex's ability to induce in vitro hASCs differentiation towards adipose phenotype was evaluated in comparison to HHA, performing Oil Red O staining and analyzing gene/protein expression of PPAR-γ, adiponectin, and leptin. Both treatments supported hASCs differentiation, with the HA hybrid complex showing better results. These outcomes may open new frontiers in regenerative medicine, supporting the injection of highly concentrated hybrid formulations in fat compartments, eventually enhancing residing staminal cell differentiation and improving cell/growth factor persistence towards tissue regeneration districts.

Superior Sensibility after Full Breast Reconstruction with Autologous Fat Transfer

BACKGROUND

With developments in screening and treatment, survival rates of breast cancer patients are increasing, and so is the number of women opting for breast reconstruction to improve their quality of life. One factor that could play an important role in improving the quality of life is breast sensibility. Therefore, the aim of this study was to explore breast sensibility in participants of the Breast Reconstruction with External Preexpansion and Autologous Fat Transfer versus Standard Therapy trial: an ongoing randomized controlled trial comparing breast reconstruction with autologous fat transfer (AFT) versus implant-based reconstruction (IBR).

METHODS

This study was conducted on participants of the Breast Reconstruction with External Preexpansion and Autologous Fat Transfer versus Standard Therapy trial who were at least 12 months after final surgery. Semmes-Weinstein monofilaments were used to measure skin sensibility in breast cancer patients who underwent breast reconstruction with either AFT or IBR following their mastectomy.

RESULTS

A total of 46 patients were included in this study, resulting in 62 breast reconstructions (28 AFT breasts and 34 IBR breasts). Significantly higher mean monofilament values were found for skin sensibility after AFT (-0.7; P < 0.001), clinically correlating to "diminished protective function," as opposed to the IBR group, with clinical values indicating "loss of protective function."

CONCLUSIONS

In this study, the authors found that breast cancer patients who underwent a mastectomy had a significantly better sensibility of the breast following AFT for total breast reconstruction as compared with IBR. Larger studies that include null measurements are required to further explore these noteworthy results of AFT.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, II.

SINGLE-CENTER ONCOLOGIC OUTCOME OF FAT TRANSFER FOR BREAST RECONSTRUCTION FOLLOWING MASTECTOMY IN 1000 CANCER CASES - A MATCHED CASE-CONTROL STUDY

BACKGROUND

Autologous fat transfer (AFT) has an important role in breast reconstructive surgery. Nevertheless, Some concerns remain with regards to its oncological safety. We present a single center case-matching study analysing the impact of AFT in cumulative incidence of local recurrences (LR).

MATERIALS AND METHODS

From a prospectively maintained database, we identified 902 patients who underwent 1025 breast reconstructions from 2005 to 2017. Data regarding demographics, tumor characteristics, surgery details and follow-up were collected. Exclusion criteria were patients with distant metastases at diagnosis, recurrent tumor or incomplete data regarding primary tumor, patients who underwent prophylactic mastectomies and breast-conserving surgeries. Statistical analysis was done to evaluate the impact of the variables on the incidence of LR. A p-value < 0.05 was considered statistically significant.

RESULTS

After 1:n case-matching, we selected 919 breasts, out of which 425 (46.2%) patients received at least one AFT session vs 494 (53.8%) control cases. LR had an overall rate of 6.8% and we found LR in 14 (3.0%) AFT cases and 54 (9.6%) controls. Statistical analysis showed that AFT did not increase risk of LR: HR 0.337 (CI 0.173-0.658), p=0.00007. Multivariate analysis identified IDC subtype and lymph node metastases to have an increased risk of local recurrences (HR > 1). Conversely, positive hormonal receptor status was associated with a reduced risk of events (HR < 1).

CONCLUSIONS

AFT was not associated with a higher probability of locoregional recurrence in patients undergoing breast reconstruction therefore it can be safely used for total breast reconstruction or aesthetic refinements.LEVEL OF EVIDENCE: 3.

Autologous Fat Grafting to the Breast: An Educational Review

Autologous fat grafting (AFG) is a technique that is increasingly utilized in breast cosmetic and reconstructive surgery. In this procedure, fat is aspirated by liposuction from one area of the body and injected into the breast. The procedure and process of AFG has evolved over the last few decades, leading to more widespread use, though there is no standard method. Autologous fat grafting is generally considered a safe procedure but may result in higher utilization of diagnostic imaging due to development of palpable lumps related to fat necrosis. Imaging findings depend on surgical technique but typically include bilateral, symmetric, retromammary oil cysts and scattered dystrophic and/or coarse calcifications when AFG is used for primary breast augmentation. More focal findings occur when AFG is used to improve specific areas of cosmetic deformity, scarring, or pain following breast cancer surgery. As with any cause of fat necrosis, imaging features tend to appear more benign over time, with development of rim calcifications associated with oil cysts and a shift in echogenicity of oil cyst contents on ultrasound towards anechoic in some cases. This article reviews the AFG procedure, uses, complications, and imaging findings.

A Short-Term High-Fat Diet Improved the Survival of Fat Grafts in Mice by Promoting Macrophage Infiltration and Angiogenesis

Background: Adipose tissue is an ideal filler material that is widely used for soft tissue defects. But the low survival rate and complications associated with such grafts pose a serious challenge, which limits their clinical application. Adipose tissue is a metabolic diet-responsive tissue; however, the influence of diets on fat grafting remains ambiguous.

Methods: We extracted inguinal fat pads from C57/BL6 male mice, and transplanted them into the dorsal region of recipient mice (0.3 ml). Post-fat-grafting, mice (n = 54) were randomized into three groups, namely normal diet (ND), high carbohydrate diet (HC), and high-fat diet (HF). Structural changes were assessed by histological staining. Lipolysis activity and vascular regeneration of grafts on day 30 were analyzed using real-time polymerase chain reaction, immunofluorescence, and western blotting.

Results: The grafts of mice on HC and HF diets exhibited significantly fewer oil cysts and larger volume retention (0.18 ± 0.01, 0.21 ± 0.01, and 0.25 ± 0.01 ml, for ND, HC, and HF group, respectively, p < 0.05) on day 90. In comparison, grafts for the mice belonging to the HF groups exhibited higher expression of lipolysis-related genes, including adipose triglyceride lipase (ATGL), hormone-sensitive lipase (HSL), and carnitine palmitoyltransferase 1 (CPT1), on day 30. Furthermore, increased infiltration of macrophages (F4/80+) and the higher expression of angiogenesis genes were reported in the HF groups.

Conclusion: Altogether, the administration of short-term HF diet remarkably enhanced angiogenesis and improved the quality of fat grafts, which was characterized by fewer oil cysts and higher long-term volume retention. The possible mechanisms may be due to the increased macrophage infiltration, and the promoted angiogenesis in HF grafts.

Punctual Breast Implant Rupture following Lipofilling: Only a Myth?

Background

Lipofilling techniques are widespread in clinical practice as a complement to breast reconstruction, despite posing some risk. Punctual implant rupture following a fat transfer is one of the possible complications, which has not been properly reported yet and is probably being underdiagnosed. The aim of this paper is to report key facts for appropriate diagnosis of this clinical chart.

Case Report

We present the case of a 47-year-old woman with a bilateral prosthetic breast reconstruction who was treated with autologous fat graft for upper pole enhancing and scar improvement. The patient developed an early unilateral breast capsular contracture after the fat graft procedure, with normal radiological exploration. Surgical findings showed intraprosthetic fat deposits and a punctual implant rupture.

Conclusions

Punctual breast implant rupture is a possible complication of lipofilling that is usually not suspected at first consultation and might be underdiagnosed based on radiological findings, so investigating clinical signs should necessarily be a prerequisite to diagnosis.

Oncological Safety of Autologous Fat Grafting in Breast Reconstruction after Mastectomy for cancer: A case-control study

OBJECTIVE

The use of autologous fat grafting in the context of breast reconstruction is still a matter of controversy. The objective of this study was to compare the local relapse rate in women who had a fat grafting session in the context of breast reconstruction after breast cancer management, to those who had breast reconstruction without fat grafting.

METHODS

We performed a retrospective, monocentric, case-control study from January 2007 to December 2017 in our hospital. The cases included women who underwent breast reconstruction with autologous fat grafting and controls, undergoing breast reconstruction without fat grafting. We compared survival and local recurrence between the two groups.

RESULTS

412 women were included: 109 (26.5%) in the lipofilling group and 303 women (73.5%) in the "no lipofilling" group. In the overall study population, lipofilling did not appear to be a predictive factor for recurrence, HR = 1.39 [0.63 - 3.06], p = 0.41; or a predictive factor for overall survival, HR = 0.84 [0.23 - 3.02], p = 0.79, or for distant metastases, HR = 1.10 [0.43 - 2.79], p = 0.84. In contrast, in the subgroup of women treated for invasive cancer, the multivariate analysis showed that lipofilling in this context was an independent predictive factor for local recurrence (HR= 5.06 [1.97 - 10.6], p = 0.04).

CONCLUSION

we found an increased risk of local recurrence after lipofilling in women who were managed for invasive breast cancer. This suggests that special consideration should be given to women who have had invasive breast cancer before lipofilling.

Effects of radiation and chemotherapy on adipose stem cells: Implications for use in fat grafting in cancer patients

Autologous fat transplantation is a versatile tool in reconstructive surgery. Adipose-derived stem cells (ASCs) increase survival of fat grafts and thus are increasingly used for breast reconstruction in breast cancer patients. However, radiation and/or chemotherapy have been proposed to inhibit soft tissue regeneration in wound healing thus suggesting alteration in stem cell pathways. Therefore, elucidating effects of radiation and chemotherapy on ASCs is critical if one desires to enhance the survival of fat grafts in patients. This review outlines our work evaluating the function and recoverability of ASCs from radiation or chemotherapy patients, focusing specifically on their availability as a source of autologous stem cells for fat grafting and breast reconstruction in cancer patients. Even though evidence suggests radiation and chemotherapy negatively influence ASCs at the cellular level, the efficiency of the isolation and differentiation capacity did not appear influenced in patients after receiving chemotherapy treatment, although fat from radiated patients exhibited significantly altered ASC differentiation into endothelial-like cells. Further, the in vitro growth rates of patient’s ASCs do not differ significantly before or after treatment. Taken together, these studies suggest ASCs as an important new tool for grafting and reconstruction even when radiation and chemotherapy treatment are involved.

Autologous Fat Grafting for Oncologic Patients: A Literature Review

Autologous fat grafting (AFG) serves as an effective method to address volume defects, contour irregularities, and asymmetry in both aesthetic and reconstructive procedures. In recent years, there has been growing concern about the potential of cancer recurrence and interference with cancer surveillance in oncologic patients receiving AFG. The adipose tissue contains adipose-derived stem cells (ASCs), a specific type of mesenchymal stem cells, that facilitate secretion of numerous growth factors which in turn stimulate tissue regeneration and angiogenesis. As such, it has been theorized that ASCs may also have the potential to stimulate cancer cell proliferation and growth when used in oncologic patients. Multiple research studies have demonstrated the ability of ACSs to facilitate tumor proliferation in animal models. However, clinical research in oncologic patients has yielded contradictory findings. Although the literature pertaining to oncologic safety in head and neck, as well as sarcoma, cancer patients remains limited, studies demonstrate no increased risk of tumor recurrence in these patient populations receiving AFG. Similarly, both the efficacy and safety of AFG have been well established in breast cancer patients through numerous clinical studies. More recently, preclinical research in animal models has shown that AFG has the potential to facilitate tissue regeneration and improve joint contracture following irradiation. Ultimately, further research is needed to elucidate the safety of AFG in a variety of oncologic patients, as well as explore its use in tissue regeneration, particularly in the setting of radiotherapy. Level of Evidence: 4.

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. χ 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.

Safety and Effectiveness of Autologous Fat Grafting after Breast Radiotherapy: A Systematic Review and Meta-Analysis

BACKGROUND

The purpose of this study was to evaluate the safety and effectiveness of autologous fat grafting after radiotherapy.

METHODS

All studies published before December of 2019 were collected by searching on PubMed, Embase, Cochrane, Web of Science, China National Knowledge Infrastructure, and Wanfang Data. After independently screening the studies and extracting the data, Stata was applied to perform meta-analysis.

RESULTS

Seventeen qualified articles were eventually included, involving a total of 1658 patients, of which 1555 underwent autologous fat grafting. Overall, empirically from the data, the use of autologous fat grafting after radiotherapy does not increase the incidence of complications or the risk of tumor recurrence. Through statistical analysis, the authors found that 152 patients suffered complications after undergoing autologous fat grafting [152 of 1555 (9.8 percent)]; 72 patients suffered complications after undergoing postradiotherapy autologous fat grafting [72 of 1040 (6.9 percent)], including seven cases of tumor recurrence [seven of 1040 (0.7 percent)]; and 80 patients suffered complications after undergoing autologous fat grafting without radiotherapy [80 of 515 (15.5 percent)], including seven cases of tumor recurrence [seven of 515 (1.4 percent)]. The authors also found that 970 of 1040 patients (93.3 percent) were satisfied with the results of postradiotherapy autologous fat grafting for breast reconstruction.

CONCLUSIONS

This study has provided an evidence-based conclusion supporting the use of autologous fat grafting for breast reconstruction after radiotherapy. Autologous fat grafting can effectively correct breast deformity and contracture caused by breast-conserving therapy and radiotherapy and increase patient satisfaction without increasing the rate of tumor recurrence.

Evaluation of the ex vivo Effects of Tamoxifen on Adipose-Derived Stem Cells: A Pilot Study

Autologous fat grafting (AFG) is a safe and minimally invasive procedure to correct soft tissue defects. The benefit of AFG is attributed to adipose-derived stem cells (ASCs) in fat tissue graft. This technique is useful also in patients undergoing reconstructive surgery following quadrantectomy for breast cancer. However, these patients are frequently treated with tamoxifen. We evaluated the ex vivo effects of tamoxifen on ASCs to understand if cellular functions of ASCs are affected. We selected 24 female patients; 10 of which were breast cancer patients treated with quadrantectomy and tamoxifen. As control group, we selected 14 healthy female subjects (9 premenopausal and 5 menopausal). We found that tamoxifen has no effect on cellular proliferation, VEGF secretion or apoptosis of ASCs. The gene expression assessment demonstrated no impairment in differentiation capacity of ASCs. Our results showed that tamoxifen has no effect on cellular functions of ASCs for the first time in an ex vivo single-center study.

Oncological outcomes of lipofilling in breast reconstruction: a matched cohort study with 250 patients

Background

Fat grafting is a procedure commonly used in breast reconstruction nowadays. Nevertheless, its oncological safety remains controversial. The potential risk that progenitor cells included in fat graft tissue may contribute to disease progression in patients with breast cancer is still debatable. We have designed a matching-cohort study with 250 patients with history of breast cancer trying to elucidate an answer for this question.

Methods

We selected 250 patients with a history of breast cancer in our hospital, between 2011 and 2019. A total of 125 patients (cases) had a history of breast cancer reconstructed with fat grafting. The additional 125 patients are matched controls. We analyzed the distribution of eight different variables within the cases and their matched controls: date of first oncological surgery, age, type of oncological surgery, histological subtype, Her-2 status, pN, smoking habit and diabetes mellitus. The objective of this study was to analyze the influence of fat grafting over breast cancer recurrence.

Results

There are not statistically significant differences in breast cancer locoregional recurrences (P=0.183), distant metastases (P=0.200) or total recurrences (P=0.065) amongst the two groups (cancer cases and matched controls).

Conclusions

Our study adds more information over the oncological safety of fat grafting. These findings should encourage long-term prospective trials to provide surgeons with accurate information regarding the role of lipofilling on breast neoplasms.

Silicone Implant Versus Silicone Implant Assisted by Stromal Enriched Lipograft Breast Augmentation: A Prospective Comparative Study

Background: Implant-assisted breast augmentation is among the most performed surgeries performed by plastic surgeons today. This prospective study evaluated the patient satisfaction and complication rates using high-profile round silicone implant alone (traditional breast augmentation) Group A versus the high-profile round silicone implant assisted with stromal enriched lipograft (composite breast augmentation) Group B. Methods: A total of 50 female patient candidates to undergo breast augmentation between January to September 2017 were randomly assigned to either group. The periareolar technique for breast augmentation and the subfascial plane were used in both groups for the insertion of the high-profile round silicone implants. The stromal enriched lipograft (SEL) was used in Group B for the preparation of the autologous fat grafting to the breast. The satisfaction of each patient with body appearance following breast augmentation was rated using an already published scale of 1–5. The rate of complications was analysed. Results: AS performed all the surgeries. In Group A, the age range was between 19 and 48 years (mean of 22.5 years). In Group B, the age range was between 20 and 47 years (mean of 24.1 years). The average BMI of Group A was 24 m/kg² and 23 m/kg² of Group B. Patient satisfaction meta-analysis for Group A and B at 12 months shows that patients in Group B expressed a satisfaction that is superior when compared to Group A patients. The ability to camouflage the implant could explain the higher satisfaction rates in Group B. The rate of complications appears similar in both groups. Conclusions: Composite breast augmentation using a combination of round high-profile implants and SEL in breast augmentation can achieve a higher patient satisfaction and aesthetic outcome as compared to the round high-profile breast augmentation alone. The technique is safe, simple and fast with low complication rates. Large multicentre, controlled, prospective studies need to be performed to further confirm the favourable results that were observed in this study.

Isolation and identification of adipose-derived stromal/stem cells from breast cancer patients after exposure neoadjuvant chemotherapy

BACKGROUND

With recent research advances, adipose-derived stromal/stem cells (ASCs) have been demonstrated to facilitate the survival of fat grafts and thus are increasingly used for reconstructive procedures following surgery for breast cancer. Unfortunately, in patients, following radiation and chemotherapy for breast cancer suggest that these cancer treatment therapies may limit stem cell cellular functions important for soft tissue wound healing. For clinical translation to patients that have undergone cancer treatment, it is necessary to understand the effects of these therapies on the ASC's ability to improve fat graft survival in clinical practice.

AIM

To investigate whether the impact on ASCs function capacity and recovery in cancer patients may be due to the chemotherapy.

METHODS

ASCs were isolated from the cancerous side and noncancerous side of the breast from the same patients with receiving neoadjuvant chemotherapy (NAC) or not-receiving NAC. ASCs were in vitro treated with 5-fluorouracil (5-FU), doxorubicin (DXR), and cyclophosphamide (Cytoxan) at various concentrations. The stem cells yield, cell viability, and proliferation rates were measured by growth curves and MTT assays. Differentiation capacity for adipogenesis was determined by qPCR analysis of the specific gene markers and histological staining.

RESULTS

No significant differences were observed between the yield of ASCs in patients receiving NAC treatment and not-receiving NAC. ASCs yield from the cancerous side of the breast showed lower than the noncancerous side of the breast in both patients receiving NAC and not-receiving NAC. The proliferation rates of ASCs from patients didn't differ much before and after NAC upon in vitro culture, and these cells appeared to retain the capacity to acquire adipocyte traits simile to the ASCs from patients not-receiving NAC. After cessation and washout of the drugs for another a week of culturing, ASCs showed a slow recovery of cell growth capacity in 5-FU-treated groups but was not observed in ASCs treated with DXR groups.

CONCLUSION

Neoadjuvant therapies do not affect the functioning capacity of ASCs. ASCs may hold great potential to serve as a cell source for fat grafting and reconstruction in patients undergoing chemotherapy.

Oncologic safety of immediate autologous fat grafting for reconstruction in breast-conserving surgery

IMPORTANCE

Autologous fat grafting (AFG), or lipofilling, has been used for immediate reconstruction at the time of breast-conserving surgery in order to achieve a satisfactory cosmetic outcome in patients with breast cancer and an unfavorable tumor-to-breast volume ratio or unfavorable tumor location. However, the oncologic safety of this technique is still unclear.

OBJECTIVE

To determine whether AFG performed simultaneously with breast-conserving surgery is associated with differences in local relapse rates and disease-free survival.

DESIGN

Matched retrospective cohort study.

SETTING

Tertiary referral center.

PARTICIPANTS

Patients undergoing breast-conserving surgery with or without AFG between 2004 and 2016 were retrospectively enrolled and matched for age, staging, grade, tumor histology, and tumor immunohistochemical profile.

MAIN OUTCOME(S) AND MEASURE(S)

The cumulative incidence of locoregional recurrence (LRR) and disease-free survival were the primary end points, while distant recurrence and overall survival were the secondary end points.

RESULTS

A total of 320 patients were followed. Cases were matched with controls at a 1:4 ratio. There was no difference in LRR or distant recurrence of breast cancer between the two groups. The annual LRR rate was 0.86% in patients who received immediate AFG vs. 0.7% in patients undergoing breast-conserving surgery alone (p ≥ 0.05). Number of lymph nodes was the sole independent risk factor for local recurrence (p = 0.045). No significant differences in disease-free survival rates were found between the groups.

CONCLUSIONS AND RELEVANCE

At a mean follow-up of 5 years, no significant differences in locoregional recurrence rates were found between patients who received immediate AFG and those who underwent breast-conserving surgery alone. These findings corroborate previous research demonstrating the oncological safety of immediate AFG reconstruction, further suggesting that this technique as a safe, effective way to achieve optimal cosmetic outcomes in primary breast cancer surgery without jeopardizing oncologic outcomes.

The use of autologous fat grafts in breast surgery: A literature review

Autologous fat injection was first described roughly a century ago and has been used in surgery ever since. In addition to its use in many surgical fields, it is also frequently used for both aesthetic and reconstructive purposes in breast surgery. Since the application of fat grafting in breast surgery has steadily increased, studies investigating its reliability have simultaneously become increasingly common. Previous studies have reported that the use of fat grafting in breast surgery is reliable, but some pending questions remain about its routine use. In order to use fat grafts successfully in breast surgery, it is necessary to be familiar with the structure and content of adipose tissue, the efficacy of adipose stem cell-enriched fat grafts, the oncological safety of fat grafts, and the problems that may occur in the radiological follow-up of patients who undergo fat grafting procedures. In this literature review, we aim to discuss the use of fat grafts in breast surgery by investigating these common problems.

Extracellular Vesicles from Human Adipose-Derived Stem Cells for the Improvement of Angiogenesis and Fat-Grafting Application

BACKGROUND

The efficacy of autologous fat transplantation is reduced by fat absorption and fibrosis that are closely related to unsatisfactory vascularization. Extracellular vesicles are key components of the cell secretome, which can mirror the functional and molecular characteristics of their parental cells. Growing evidence has revealed that adipose-derived mesenchymal stem cells have the ability to enhance vascularization, which is partly ascribed to extracellular vesicles. The authors evaluated whether adipose-derived mesenchymal stem cell-derived extracellular vesicles improved vascularization of fat grafts and increased their retention rate.

METHODS

To test the angiogenesis ability of adipose-derived mesenchymal stem cell-derived extracellular vesicles, they were isolated from the supernatant of cultured human adipose-derived mesenchymal stem cells and incubated with human umbilical vein endothelial cells in vitro. Then, the vesicles were co-transplanted with fat into nude mice subcutaneously. Three months after transplantation, the retention rate and inflammatory reaction of the grafts were analyzed by histologic assay.

RESULTS

The experimental group could significantly promote migration and tube formation at the concentration of 20 μg/ml. At 3 months after transplantation, the volume of the experimental group (0.12 ± 0.03 mm) was larger compared with the blank group (0.05 ± 0.01 mm). Histology and immunohistology results demonstrated significantly fewer cysts and vacuoles, less fibrosis, and more neovessels in the extracelluar vesicle group.

CONCLUSIONS

The authors co-transplanted adipose-derived mesenchymal stem cell-derived extracellular vesicles with fat into a nude mouse model and found that the vesicles improved volume retention by enhancing vascularization and regulating the inflammatory response.

Autologous Lipotransfer - Daily Therapeutic Practice in Breast Cancer: An Intergroup Analysis Encompassing NOGGO, WSG, GBG, AWO Gyn and DGPRÄC

Background

Autologous fat transfer in breast reconstruction has become increasingly important in breast reconstructive surgery. Although the indication to obtain fat, the various operative procedures, and the risks for the patient have been addressed in a large number of studies, detailed information on the everyday use of autologous lipotransfer in breast units in Germany is still lacking.

Methods

The objective of the study was to obtain primary data on the use of autologous lipotransfer to treat breast cancer patients in Germany and to determine measures for quality assurance in the daily practice. An online questionnaire concerning breast cancer and lipofilling was sent to specialists in gynecology and plastic surgery.

Results

Two-thirds of the specialists who responded to the questionnaire use autologous lipotransfer for breast reconstruction and did not report an increase of local recurrence following lipotransfer. There were only small differences between gynecologists and plastic surgeons regarding the procedure and indication for lipotransfer. The method is highly accepted by patients and physicians, and both gynecologists and plastic surgeons rated the improvement achieved through lipofilling as 'high'.

Conclusions

The lack of randomized controlled data, especially in high-risk patients, demonstrates the necessity for a registry study on this topic. Our survey describes, in detail, the indications for lipofilling as well as its appropriate application in breast cancer patients in Germany and may thereby reduce the present therapeutic uncertainties.

Early or late recurrences of breast carcinoma are to be researched in relation to fat grafting

Not available.

Adipose-Derived Stem Cells in Aesthetic Surgery

Adipose-derived stem cells (ADSC) have come to be viewed as a ubiquitous solution for aesthetic and reconstructive problems involving loss of tissue volume and age or radiation-induced loss of tissue pliability and vascularity. As the theoretical potential of "stem cell therapy" has captured the public imagination, so the commercial potential of novel therapies is being exploited beyond scientifically sound, hypothesis-driven paradigms and in the absence of evidence establishing clinical efficacy and safety. Moreover, with variations in methods of isolation, manipulation, and reintroduction described, it is unclear how the practitioner with an interest in ADSC can harness the clinical potential in reproducible and scientifically measurable ways. This Continuing Medical Education (CME) article presents a summary of our understanding of what ADSC are, their utility within the field of aesthetic surgery, and the current and future directions for adipose stem cell research.

Adipose‑derived mesenchymal stem cells exhibit tumor tropism and promote tumorsphere formation of breast cancer cells

Mesenchymal stem cells reportedly have a marked effect on tumor growth or suppression. However, it remains uncertain whether adipose-derived mesenchymal stem cells (ADSCs) from grafted fat can contribute to breast cancer growth and recurrence. In the present study, interactions between ADSCs and MCF-7 breast cancer cells were evaluated in a Matrigel co-culture system and in an in vivo nude mouse model. Results suggested that MCF-7 cells exerted tumor tropism effects on ADSCs and this may be regulated by chemokines, such as the macrophage inflammatory protein (MIP)-1δ and MIP-3α. Additionally, ADSCs significantly induced tumorsphere formation in vitro and promoted tumorigenicity in vivo. RT-qPCR analysis indicated that tumorsphere formation by MCF-7 cells was associated with the induction of stem-like properties, which was mediated by epithelial-mesenchymal transition. Together, the present findings indicated that ADSCs exhibit tropism and induce tumorsphere formation of MCF-7 cells.

Improved patient-reported outcomes after autologous fat transplantation and corrective surgery after breast surgery

BACKGROUND

Autologous fat transplantation (AFT) is being increasingly used to improve the results after breast-conserving surgery and breast reconstruction. However, studies on patient-reported outcomes (PROs) and health-related quality of life (HRQoL) after AFT are scarce. The aim of this prospective longitudinal case-series study was to assess PRO in women who had undergone AFT after surgery for breast cancer or risk-reducing mastectomy.

METHODS

Fifty women, who had undergone breast-conserving surgery or breast reconstruction, needing corrective surgery, were consecutively included between 2008 and 2013. A 20-item study-specific questionnaire (SSQ) and the Short Form Health Survey (SF-36) were used pre-operatively and 6 months, 1 year and 2 years post-operatively, to evaluate PRO and HRQoL.

RESULTS

The patients underwent three (1-4) AFT procedures, with the injection of 164 ml (median) (range 40-516) fat. Thirty-eight and 34 patients completed the study-specific questionnaire and the SF-36, respectively, both pre-operatively and after 2 years. Sixteen of the 20 items in the SSQ were improved after 2 years, including breast size (p < 0.0001), shape (p < 0.0001), appearance (p < 0.0001), softness of the breast (p = 0.001), pain in the region (p = 0.005), scarring from previous breast surgery (p < 0.001) and willingness to participate in public physical activities (p < 0.001). HRQoL did not largely differ before and after AFT, or between the study group and a reference population.

CONCLUSIONS

AFT alone or in combination with other corrective surgical procedures, improved PRO after breast-conserving surgery and breast reconstruction in both irradiated and non-irradiated women.

Immediate reconstruction with autologous fat grafting: influence in breast cancerregional recurrence

Objective

to evaluate local and systemic recurrence of breast cancer in patients submitted to autologous fat grafting in the immediate reconstruction after conservative surgery for breast cancer.

Methods

this is a historical cohort study comparing 167 patients submitted to conservative surgery without reconstruction (conservative surgery group) with 27 patients submitted to conservative treatment with immediate graft reconstruction, following the Coleman's technique (lipofilling group). All patients had invasive carcinoma and were operated by a single surgeon from 2004 to 2011. The postoperative follow-up time was 36 months.

Results

the overall incidence of local recurrence was 2.4%. No patient in the lipofilling group had local recurrence during the study period. For systemic recurrence, the rates obtained were 3.7% (one patient) for the fat grafting group and 1.8% (three patients) for the conservative surgery group without reconstruction.

Conclusion

there was no significant difference for local or systemic recurrence in the groups studied. Immediate autologous fat grafting appears to be a safe procedure.

Autologous Fat Grafting as a Novel Antiestrogen Vehicle for the Treatment of Breast Cancer

BACKGROUND

Adipose fat transfer is increasingly used for contour corrections of the tumor bed after lumpectomy and breast reconstructions after mastectomy. The lipophilic nature of the fat tissue may render adipocytes an ideal vehicle with which to deliver a high boost of an antiestrogen to the tumor bed to serve as an adjunct systemic hormonal therapy. The authors therefore tested whether adipocytes could safely be loaded with an antiestrogen and allow for release at therapeutic concentrations to treat breast cancer.

METHODS

Adipose tissue was collected from patients undergoing autologous fat grafting. The influence of adipose tissue on tumorigenesis was determined both in vitro and in vivo using breast cancer cell lines. Ex vivo, adipose tissue was assessed for its ability to depot fulvestrant and inhibit the growth of breast cancer cell lines.

RESULTS

Adipose tissue harvested from patients did not promote breast cancer cell growth in vitro or in an in vivo mouse model. Adipose tissue was successfully loaded with fulvestrant and released at levels sufficient to inhibit estrogen receptor signaling and growth of breast cancer cells.

CONCLUSIONS

This work supports the hypothesis that adipose tissue used for autologous fat grafting can serve as a novel method for local drug delivery. As this technique is used to reconstruct a variety of postsurgical defects following cancer resection, this approach for local drug delivery may be an effective alternative in therapeutic settings beyond breast cancer.

Use of autologous fat grafting in reconstruction following mastectomy and breast conserving surgery: An updated systematic review protocol

INTRODUCTION

Use of autologous fat grafting (AFG) for breast reconstructive surgery is gaining acceptance, but concerns regarding its efficacy and safety remain. We present a protocol for a systematic review that aims to update the findings since our previous systematic review on a number of outcomes of AFG.

METHODS

The systematic review has been registered a priori (UIN: reviewregistry308). All study designs, including randomised controlled trials, cohort studies, case-controlled studies and case reports/series, reporting original data, on women undergoing AFG for breast reconstruction following mastectomy or breast conserving surgery, will be included. Six categorical outcomes will be assessed: oncological; clinical; aesthetic/functional; patient-reported; process; and radiological.The search strategy will be devised to investigate 'fat grafting and breast reconstruction'. Electronic databases will be searched, 01 April 2014 to 21 August 2017: PubMed, MEDLINE®, EMBASE, SCOPUS, CINAHL, PsychINFO, SciELO, The Cochrane Library, including the Cochrane Central Register of Controlled Trials (CENTRAL), Database of Abstracts of Reviews of Effect (DARE), the Cochrane Methodology Register, Health Technology Assessment Database, the NHS Economic Evaluation Databases and Cochrane Groups, ClinicalTrials.gov, Current Controlled Trials Database, the World Health Organisation (WHO) International Clinical Trials Registry Platform, UpToDate.com, NHS Evidence and the York Centre for Reviews and Dissemination. Grey literature will be searched. Two trained, independent teams will screen all titles and abstracts, and relevant full texts, for eligibility. Data will be extracted under standardised extraction fields into a preformatted database.

ETHICS AND DISSEMINATION

The systematic review will be published in a peer-reviewed journal and presented at national and international meetings within fields of plastic, reconstructive and aesthetic surgery, and surgical oncology. The work will be disseminated electronically and in print. Brief reports of the review and findings will be disseminated to interested parties through email and direct communication. The review aims to guide healthcare practice and policy.

Adipose-Derived Stem Cells in Novel Approaches to Breast Reconstruction: Their Suitability for Tissue Engineering and Oncological Safety

Adipose-derived stem cells (ADSCs) are rapidly becoming the gold standard cell source for tissue engineering strategies and hold great potential for novel breast reconstruction strategies. However, their use in patients with breast cancer is controversial and their oncological safety, particularly in relation to local disease recurrence, has been questioned. In vitro, in vivo, and clinical studies using ADSCs report conflicting data on their suitability for adipose tissue regeneration in patients with cancer. This review aims to provide an overview of the potential role for ADSCs in breast reconstruction and to examine the evidence relating to the oncologic safety of their use in patients with breast cancer.

Increased risk of recurrence associated with certain risk factors in breast cancer patients after DIEP-flap reconstruction and lipofilling-a matched cohort study with 200 patients

BACKGROUND

Lipofilling is performed in breast cancer patients to optimize the aesthetic outcome following breast reconstruction after mastectomy. Despite its common usage worldwide, little is known about the interaction of the lipoaspirate and dormant cancer cells. Up to date, no risk factors that increase the risk for cancer recurrence have been established. This study aims to identify risk factors for lipofilling candidates after breast cancer and questions the oncological safety of lipofilling in lymph node positive disease.

METHODS

Matched retrospective cohort study: the disease-free survival (DFS) between 100 breast cancer patients undergoing a lipofilling after their DIEP-flap reconstruction and 100 matched control patients with no subsequent lipofilling was analyzed. Further, patients were subdivided according to risk factors, which were categorized as patient-dependent factors (PDFs) and tumor-dependent factors (TDFs). DFS and hazard ratios (HR) were compared to identify potential risk factors that may increase cancer recurrence.

RESULTS

Median follow-up was 76.5 months from the mastectomy, and 31 months from the startpoint to the end of follow-up. Seven and eleven patients had recurrence in the lipofilling and control group, respectively, presenting with comparable DFS rates and an insignificant HR =0.57, 95% confidence interval (CI): 0.22-1.47, P=0.24. According to subgroup survival analysis, lipofilling increased the risk of recurrence in women with a positive nodal status (P=0.035) and a high-grade neoplasia (P=0.049).

CONCLUSIONS

No general increased recurrence risk was observed between the lipofilling and control group. The subgroup analysis identified high-grade neoplasia and positive nodal status to be a risk factor for cancer recurrence. Patients with a known node positive disease have an increased risk of occult micrometastases in their lymph nodes. Further studies are necessary to clarify whether dormant breast cancer cells in form of micrometastases in the lymph nodes can be reactivated by the factors secreted by adipose derived stem cells.

The regenerative role of adipose-derived stem cells (ADSC) in plastic and reconstructive surgery

The potential use of stem cell-based therapies for the repair and regeneration of various tissues and organs offers a paradigm shift in plastic and reconstructive surgery. The use of either embryonic stem cells (ESC) or induced pluripotent stem cells (iPSC) in clinical situations is limited because of regulations and ethical considerations even though these cells are theoretically highly beneficial. Adult mesenchymal stem cells appear to be an ideal stem cell population for practical regenerative medicine. Among these cells, adipose-derived stem cells (ADSC) have the potential to differentiate the mesenchymal, ectodermal and endodermal lineages and are easy to harvest. Additionally, adipose tissue yields a high number of ADSC per volume of tissue. Based on this background knowledge, the purpose of this review is to summarise and describe the proliferation and differentiation capacities of ADSC together with current preclinical data regarding the use of ADSC as regenerative tools in plastic and reconstructive surgery.

In Vitro Effects of Adipose-Derived Stem Cells on Breast Cancer Cells Harvested From the Same Patient

INTRODUCTION

Fat grafting for breast cancer (BrCa) reconstruction and breast augmentation has become increasingly more popular. A major area of debate and controversy is the effect of adipose-derived stem cells (ASCs) on remnant or undetected BrCa cells. We investigate the in vitro response of BrCa to ASCs in a coculture model with regards to cell migration.

METHODS

The study was approved by the institutional review board. BrCa and adipose tissue specimens either from subcutaneous breast tissue or abdominal lipoaspirate were obtained from the same patient. BrCa cells and ASCs were harvested with either explant culture and/or enzymatic digestion. Tissues were grown in cell culture flasks until adequate cell libraries were established. Adipose-derived stem cells from adipose specimens were characterized with flow cytometry. Immunofluorescence (IF) staining of the initial cell population harvested from the BrCa specimens confirmed the presence of CD24, an epithelial marker of BrCa. A homogenous CD 24+/CD 90- BrCa cell population was obtained with flowcytometric cell sorting. The in vitro migration of BrCa cells was examined in coculture with and without ASCs.

RESULTS

Adipose-derived stem cells harvested from the adipose specimens were positive for mesenchymal stem cell markers CD 105, CD 90, CD 73, and CD 44 and negative for lymphocyte cell marker CD 34 and leukocyte marker CD 45. The percentage of the CD 24+/CD 90- BrCa cells in the initial cell population harvested from BrCa specimens was 0.61%. The BrCa cells morphologically had large nuclei and small cytoplasm in clusters under the light microscope, suggesting a cancer cell phenotype. CD 24 expression on the surface of BrCa cells was confirmed with IF staining. The number of BrCa cells migrated in ASCs coculture was approximately 10 times higher than the number of BrCa cells migrated in BrCa cell only cultures.

CONCLUSIONS

Adipose-derived stem cells significantly increase the migration capacity of BrCa cells in vitro in cocultures. This should be taken into consideration when performing fat grafting to the breast especially in patients with a history of BrCa or strong family history of BrCa.

Cancer Risk after Fat Transfer: A Multicenter Case-Cohort Study

BACKGROUND

Fat transfer is an increasingly popular method for refining postmastectomy breast reconstructions. However, concern persists that fat transfer may promote disease recurrence. Adipocytes are derived from adipose-derived stem cells and express adipocytokines that can facilitate active breast cancer cells in laboratory models. The authors sought to evaluate the association between fat transfer to the reconstructed breast and cancer recurrence in patients diagnosed with local or regional invasive breast cancers.

METHODS

A multicenter, case-cohort study was performed. Eligible patients from four centers (Memorial Sloan Kettering, M. D. Anderson Cancer Center, Alvin J. Siteman Cancer Center, and the University of Chicago) were identified by each site's institutional tumor registry or cancer data warehouse. Eligibility criteria were as follows: mastectomy with immediate breast reconstruction between 2006 and 2011, age older than 21 years, female sex, and incident diagnosis of invasive ductal carcinoma (stage I, II, or III). Cases consisted of all recurrences during the study period, and controls consisted of a 30 percent random sample of the study population. Cox proportional hazards regression was used to evaluate for association between fat transfer and time to recurrence in bivariate and multivariate models.

RESULTS

The time to disease recurrence unadjusted hazard ratio for fat transfer was 0.99 (95 percent CI, 0.56 to 1.7). After adjustment for age, body mass index, stage, HER2/Neu receptor status, and estrogen receptor status, the hazard ratio was 0.97 (95 percent CI, 0.54 to 1.8).

CONCLUSION

In this population of breast cancer patients who had mastectomy with immediate reconstruction, fat transfer was not associated with a higher risk of cancer recurrence.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Systematic review: The oncological safety of adipose fat transfer after breast cancer surgery

OBJECTIVES

Oncological concerns have risen around the safety of adipose fat transfer (AFT) after breast cancer surgery. In this article, we present the clinical and molecular evidences, and discuss the current contradiction between them.

MATERIALS AND METHODS

Every clinical trial and experimental study on AFT and its oncological influences was screened. Between September 2014 and September 2016, 856 articles from four databases were found. 105 core articles were selected.

RESULTS

A total of 18 clinical studies have been published. The loco-regional recurrence (LRR) incidence rates range between 0 and 3.90% per year. For the mastectomy and breast conservative therapy group separately, a LRR per year between 0 and 1.62% and 0-3.90 has been reported, respectively. Some studies included a matched control group and found no significant difference between cases and controls, with the exception of a subgroup of patients with intraepithelial breast carcinoma. Adipose derived mesenchymal stem cells have a potential oncogenic effect on residual cancer cells after breast cancer surgery. Numerous signalling proteins and pathways have been described that can stimulate tumour initiation and growth.

CONCLUSION

There is a contradiction between experimental and clinical findings. Numerous adipokines have been discovered that could potentially promote tumour initiation and growth, but clinical studies fail to point out a significant increase in LRR in patients who receive AFT after breast cancer surgery. More prospective studies are needed with a sufficient follow-up time and analysis of some critical factors, such as adjuvant radiotherapy and hormonal therapy, the origin and volume of the injected fat, and genetic influences.

Breast cancer and fat grafting: efficacy, safety and complications-a systematic review

Autologous fat grafting (AFG) or lipofilling is nowadays a popular technique for breast reconstruction after breast cancer surgery. There is debate regarding the oncological safety and risks of this procedure in breast cancer patients. A systematic review of the literature published between January first 1995 and October first 2016 was conducted regarding the efficacy, safety and complications of this technique in breast cancer patients after their cancer treatment. The databases PubMed, Science Direct and Thomson Reuters Web of Science were used to search for qualified articles. Inclusion criteria were women with a personal history of breast cancer and at least one lipofilling procedure. Only studies containing a minimum of 20 patients were included in this systematic review. The search yielded a total of 23 suitable articles: 18 case series, 4 retrospective cohort studies and one prospective cohort study. The systematic review encompassed a total of 2419 patients. Medical imaging was used in the majority of the studies to assess the follow-up. Mammography was the most popular technique (65.2%), followed by ultrasound (47.8%) and MRI (30.4%). The prevalence of complications was the following: fat necrosis in 5.31%, benign lesions, like cysts or calcifications in 8.78%, infections in 0.96% and local cancer recurrence in 1.69%. AFG or lipofilling appears to be an oncological safe technique with a low morbidity in women with a history of breast cancer. In order to have a better understanding and evidence of the oncological safety a randomised controlled trial is urgently needed. We further recommend that all AFG be registered in the cancer register.

Fat grafting for breast cancer patients: From basic science to clinical studies

Fat grafting in the surgical treatment of breast cancer has become popular in a short period of time because of the rising expectations of good esthetic results by the patients as well as the simplicity of the technique; however, the oncological safety for breast cancer patients remains a matter of debate. The procedure raises many questions considering that recent in-vitro studies have shown that fat grafting could promote tumor recurrence through diverse mechanisms, or even facilitate distant metastasis. We present a review of the currently available experimental and clinical data in order to describe and discuss patient selection criteria following breast cancer surgery.

Advances in Adipose-Derived Stem Cells Isolation, Characterization, and Application in Regenerative Tissue Engineering

Obesity is a complex, multifactorial disease that has been extensively researched in recent times. Obesity is characterized by excess deposition of adipose tissue in response to surplus energy. Despite the negative connotations of adipose tissue (AT), it serves as a critical endocrine organ. Adipose tissue is a source of several adipokines and cytokines which have been deemed important for both normal metabolic function and disease formation. The discoveries of metabolically active brown AT in adult humans and adipose tissue derived stem cells (ADSC) have been key findings in the past decade with potential therapeutic implications. ADSCs represent an enticing pool of multipotent adult stem cells because of their noncontroversial nature, relative abundance, ease of isolation, and expandability. A decade and a half since the discovery of ADSCs, the scientific community is still working to uncover their therapeutic potential in a wide range of diseases. In this review, we provide an overview of the recent developments in the field of ADSCs and examine their potential use in transplantation and cell-based therapies for the regeneration of diseased organs and systems. We also hope to provide perspective on how to best utilize this readily available, powerful pool of stem cells in the future.

Interaction Between Breast Cancer Cells and Adipose Tissue Cells Derived from Fat Grafting

BACKGROUND

Adipose tissue transplantation has the benefit of providing both regenerative and aesthetic outcomes in breast cancer treatment. However, the transplanted tissue can stimulate the growth of residual cancer cells.

OBJECTIVES

The aim of this study is to identify the interactions between adipose tissue cell subpopulations and human cancer cell lines.

METHODS

Intact adipose tissue from lipofilling procedures as well as fibroblasts derived from adipose tissue, were cocultured in the presence of MDA-MB-231, MCF-7 e ZR-75-1 breast cancer cell lines. The influence on cancer cell lines of fibroblasts, induced to differentiate into specific adipocytes, was also assayed.

RESULTS

All cancer cell lines displayed a significant increase in proliferation rate when cocultured in the presence of either intact adipose tissue or induced adipocytes. To a lesser extent, uninduced fibroblasts stimulate breast cancer cell proliferation.

CONCLUSIONS

Recent studies have shown that the microenvironment surrounding breast cancer cells may stimulate growth and promote progression of residual cancer cells when surgery is performed on the main tumor mass. Accordingly, the graft of adipose tissue could potentially promote or accelerate the development of a subclinical tumor or support its locoregional recurrence. Our data suggest that adipocytes have a remarkable influence on the proliferation of cancer cell lines. The oncological safety of the lipofilling procedure outcome is still debated; thus, further studies and consistent follow-up examination are needed.

Advances in Adipose-Derived Stem Cells Isolation, Characterization, and Application in Regenerative Tissue Engineering

Obesity is a complex, multifactorial disease that has been extensively researched in recent times. Obesity is characterized by excess deposition of adipose tissue in response to surplus energy. Despite the negative connotations of adipose tissue (AT), it serves as a critical endocrine organ. Adipose tissue is a source of several adipokines and cytokines which have been deemed important for both normal metabolic function and disease formation. The discoveries of metabolically active brown AT in adult humans and adipose tissue derived stem cells (ADSC) have been key findings in the past decade with potential therapeutic implications. ADSCs represent an enticing pool of multipotent adult stem cells because of their noncontroversial nature, relative abundance, ease of isolation, and expandability. A decade and a half since the discovery of ADSCs, the scientific community is still working to uncover their therapeutic potential in a wide range of diseases. In this review, we provide an overview of the recent developments in the field of ADSCs and examine their potential use in transplantation and cell-based therapies for the regeneration of diseased organs and systems. We also hope to provide perspective on how to best utilize this readily available, powerful pool of stem cells in the future.

Occurrence of Breast Mucinous Carcinoma After Autologous Fat Grating for Breast Augmentation

Autologous fat grafting is commonly performed in reconstructive breast surgery as well as in aesthetic breast augmentation surgery. Nevertheless, little is known about the interaction between fat grafts and cancer. A 36-year-old patient had undergone bilateral breast augmentation with autologous fat grafting. Two months after surgery, she perceived two small palpable indurations in the right breast. Nine months after the procedure, the lumps grew bigger and lumpectomy was performed. Histologic examination of the specimens showed mucinous carcinoma of the breast. This case raises once again the question about the possible links between breast cancer and fat grafts. The level of evidence is level V.

NO LEVEL ASSIGNED

This journal requires that authors assign a level of evidence to each article. For a full description of these Evidence-Based Medicine ratings, please refer to the Table of Contents or the online Instructions to Authors www.springer.com/00266.