Locoregional recurrence risk after lipofilling in breast cancer patients

Oncologic safety of autologous fat grafting in primary breast reconstruction after mastectomy for cancer

INTRODUCTION

Autologous fat transfer (AFT) is widely used to improve results of breast reconstructive surgery, but its safety is controversial. Our objective was to evaluate the oncologic safety of AFT in a homogeneous population of patients who underwent a total mastectomy with immediate reconstruction for breast cancer.

METHODS

We performed a retrospective cohort study by identifying all patients who underwent immediate breast reconstruction after mastectomy for breast cancer from 2007 to 2015 in our center. A patient group with AFT performed in the 24 months after mastectomy was compared to a control group.

RESULTS

Five hundred fifty cases were included, of whom 136 (24.7%) underwent at least one fat graft transfer. Median age was 51 years. Reconstruction was performed in 465 (84.5%) with an implant reconstruction. The median time from mastectomy to AFT was 13.8 months. The median follow up was 55.2 months. A total of 53 events were observed, including 10 (7.4%) in the AFT group and 43 (10.4%) in the control group. There was no difference in 5-year recurrence-free survival (RFS) between the groups. In the subgroup analysis, only lymph node involvement in patients who underwent AFT in the first 24 months after oncologic surgery appeared as a risk factor of recurrence. Among the 104 patients with lymph node involvement, 5-year RFS was 69.2% in patients with lipofilling vs 92.5% in patients without it (p = 0 0.0351).

CONCLUSION

Performing early lipofilling in primary breast reconstruction after mastectomy for cancer seems to be oncologically safe. Lymph node involvement increases the risk of recurrence in this population.

Comment on "Reverse Expansion Following Nipple Sparing Mastectomy: A Natural, Safe and Effective Autologous Technique for Breast Reconstruction"

Level of Evidence IV 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 .

Optimizing Prepectoral Implant Placement and Concomitant Fat Grafting After Tissue Expansion

BACKGROUND

Prepectoral implant-based breast reconstruction is often supplemented by autologous fat grafting to optimize aesthetic outcomes. This usually entails several rounds of modest fat transfer to minimize risk of necrosis; however, the limits of fat grafting at expander exchange are not known.

METHODS

A single-institution retrospective review from July 2016 to February 2022 was performed of all patients who underwent (1) mastectomy, (2) prepectoral tissue expander placement, (3) expander exchange for implant, and (4) at least one round of autologous fat transfer. Student t test and χ2 test were used.

RESULTS

A total of 82 breasts underwent a single round of fat grafting during implant placement (group 1); 75 breasts underwent fat grafting that occurred in multiple rounds and/or in delay to implant placement (group 2). Group 1 received more fat at the time of implant placement (100 mL; interquartile range, 55-140 mL; P < 0.001) and underwent fewer planned operative procedures compared with group 2 (1.0 vs 2.2, P < 0.001). Total fat volume in group 2 did not significantly exceed that of group 1 until after 3 rounds of fat transfer (128.5 mL; interquartile range, 90-130 mL; P < 0.01). There was no difference in the rate of fat necrosis between groups after the first round (15.9% vs 9.3%, P = 0.2) and final round (15.9% vs 12.0%, P = 0.5) of fat grafting. Complication rates were similar between groups (3.7% vs 8.0%, P = 0.2).

CONCLUSIONS

A 2-stage approach of prepectoral tissue expander placement with single round of larger volume fat transfer at expander exchange reduces overall number of operative procedures without increased risks.

Association of Fat Graft with Breast Cancer Recurrence in Implant-Based Reconstruction: Does the Timing Matter?

PURPOSE

In two-stage prosthetic breast reconstruction, autologous fat graft (AFG) is often conducted simultaneously with the second-stage operation, which is usually performed shortly after mastectomy. There is a paucity of studies evaluating whether conducting AFG early, with a relatively short interval from the primary operation, is oncologically safe. This study aimed to evaluate potential associations of AFG with breast cancer prognosis, focusing on its timing.

METHODS

Patients with invasive breast cancer who underwent immediate two-stage prosthetic reconstruction following mastectomy between 2011 and 2016 were identified. They were categorized into two groups by whether AFG was performed during the second-stage operation. Cumulative incidence of oncologic events was compared between the two groups, after stratifying patients by the time interval between mastectomy and the second-stage operation (≤ 12 months vs. > 12 months).

RESULTS

Of 267 cases that met the selection criteria, 203 underwent the second-stage operation within 12 months of mastectomy. AFG was performed for 112 cases and was not performed in 91 cases. The two groups showed similar baseline characteristics including tumor stage and adjuvant treatments. Compared with the control, AFG was associated with lower locoregional recurrence-free survival and disease-free survival, and this difference remained significant after adjusting for other variables including tumor stage. In the 64 cases undergoing the operation after 12 months following mastectomy, oncologic outcomes did not differ between the two groups.

CONCLUSION

Our results suggest that AFG timing in relation to mastectomy may be associated with risks for breast cancer recurrence.

Free Flap Fat Volume is Not Associated With Recurrence or Wound Complications in Oral Cancer

Objective

Adipose stem cells (ASCs) have been shown in many preclinical studies to be potent suppressors of the immune system. Prior studies suggest that ASCs may promote cancer progression and wound healing. However, clinical studies investigating the effects of native, or fat-grafted adipose tissue on cancer recurrence have generated mixed results. We investigated whether adipose content in reconstructive free flaps for oral squamous cell carcinoma (OSCC) is associated with disease recurrence and/or reduction in wound complications.

Study Design

Retrospective chart review.

Setting

Academic medical center.

Methods

We performed a review of 55 patients undergoing free flap reconstruction for OSCC over a 14-month period. Using texture analysis software, we measured the relative free flap fat volume (FFFV) in postoperative computed tomography scans and compared fat volume with patient survival, recurrence, and wound healing complications.

Results

We report no difference in mean FFFV between patients with or without recurrence: 13.47 cm³ in cancer-free survivors and 17.99 cm³ in cases that recurred (p = .56). Two-year recurrence-free survival in patients with high and low FFFV was 61.0% and 59.1%, respectively (p = .917). Although only 9 patients had wound healing complications, we found no trend in the incidence of wound healing complications between patients with high versus low FFFV.

Conclusion

FFFV is not associated with recurrence or wound healing in patients undergoing free flap reconstruction for OSCC, suggesting adipose content should not be of concern to the reconstructive surgeon.

Meta-Analysis of the Oncological Safety of Autologous Fat Grafting After Breast Cancer on Basic Science and Clinical Studies

BACKGROUND

The purpose of the present study was to comprehensively evaluate the oncological safety of autologous fat grafting after breast cancer by combining experimental and clinical studies.

METHODS

All studies published before August 2021 were collected by searching PubMed, Cochrane, Embase, Web of Science, SINOMED, and China National Knowledge Infrastructure. After screening the research and extracting the data, RevMan was used to perform the meta-analysis.

RESULTS

Five basic science studies and 26 clinical studies, involving a total of 10,125 patients, were eventually included. In the basic science studies, adipose-derived stem cells promoted breast cancer growth, but fat grafting and adipose-derived stem cells plus fat grafting were not associated with breast cancer growth. An overall analysis of clinical studies showed that autologous fat grafting does not increase the risk of breast cancer recurrence. Subgroup analyses indicated that autologous fat grafting did not increase the risk of breast cancer recurrence in Asian or Caucasian patients, in patients undergoing breast-conserving surgery or modified radical mastectomy, in patients with in situ carcinomas or invasive carcinomas, or in patients undergoing postoperative radiotherapy.

CONCLUSION

This study combined experimental and clinical studies to conclude that autologous fat grafting does not increase the risk of breast cancer recurrence. However, the experimental results suggest that adipose-derived stem cells should be used with caution after breast cancer surgery.

LEVEL OF EVIDENCE III

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 .

Review of Autologous Fat Grafting in Postmastectomy Reconstruction Patients: Nonroutine Diagnostics and Oncologic Safety

Autologous fat grafting (FG) is increasingly used as an adjunctive reconstruction technique to augment volume, achieve symmetry, and improve contour deformities. This study aims to characterize the oncologic and surgical safety of FG in women undergoing autologous breast reconstruction (ABR) or implant-based reconstruction (IBR).

METHODS

A retrospective chart review was performed for all patients undergoing FG at a multi-site single health system between 2015 to 2018. A total of 228 eligible breasts from 155 patients were identified using Current Procedural Terminology codes. Patients were divided by reconstructive technique. Bivariate analyses compared baseline characteristics and post-FG outcomes.

RESULTS

Mean age for patients undergoing ABR (129 breasts) was 52.8 years compared to 48.6 years for those undergoing IBR (99 breasts; P = 0.002). A heavier volume of fat was grafted per ABR breast (143.8mL) than per IBR breast (102.2mL; P = 0.002). Forty-seven (20.6%) breasts required FG revision, more frequently in ABR breasts (31.0%) than IBR breasts (7.1%; P < 0.001). Following FG, 17.5% of patients experienced a palpable mass, and 18.9% of breasts underwent nonroutine diagnostics or procedures, with no difference between ABR and IBR groups. Most biopsies noted benign findings such as fat necrosis (2.2%) or a benign mass (0.9%), with recurrence only noted in two patients (0.9%). Mean follow-up was 20.4 months.

CONCLUSION

FG is a safe, surgically simple procedure more commonly performed in ABR breasts. FG use in ABR and IBR breasts is oncologically safe, with no impairment in breast surveillance and low rates of locoregional recurrence, but possibly increased incidence of nonroutine imaging and biopsies.

Adipose tissue-to-breast cancer crosstalk: Comprehensive insights

The review focuses on mechanistic evidence for the link between obesity and breast cancer. According to the IARC study, there is sufficient evidence that obesity is closely related to a variety of cancers. Among them, breast cancer is particularly disturbed by adipose tissue due to the unique histological structure of the breast. The review introduces the relationship between obesity and breast cancer from two aspects, including factors that promote tumorigenesis or metastasis. We summarize alterations in adipokines and metabolic pathways that contribute to breast cancer development. Breast cancer metastasis is closely related to obesity-induced pro-inflammatory microenvironment, adipose stem cells, and miRNAs. Based on the mechanism by which obesity causes breast cancer, we list possible therapeutic directions, including reducing the risk of breast cancer and inhibiting the progression of breast cancer. We also discussed the risk of autologous breast remodeling and fat transplantation. Finally, the causes of the obesity paradox and the function of enhancing immunity are discussed. Evaluating the balance between obesity-induced inflammation and enhanced immunity warrants further study.

Influence of Tamoxifen on Different Biological Pathways in Tumorigenesis and Transformation in Adipose-Derived Stem Cells, Mammary Cells and Mammary Carcinoma Cell Lines—An In Vitro Study

Breast carcinoma is one of the most common malignant tumors in women. In cases of hormone-sensitive cells, tamoxifen as an anti-estrogenic substance is a first line medication in the adjuvant setting. The spectrum of autologous breast reconstructions ranges from fat infiltrations to complex microsurgical procedures. The influence of adipose-derived stem cells (ASC) on the tumor bed and a possibly increased recurrence rate as a result are critically discussed. In addition, there is currently no conclusive recommendation regarding tamoxifen-treated patients and autologous fat infiltrations. The aim of the present study was to investigate the effect of tamoxifen on the gene expression of a variety of genes involved in tumorigenesis, cell growth and transformation. Mammary epithelial cell line and mammary carcinoma cell lines were treated with tamoxifen in vitro as well as co-cultured with ASC. Gene expression was quantified by PCR arrays and showed increased expression in the mammary carcinoma cell lines with increasing time of treatment and concentration of tamoxifen. The data presented can be considered as an addition to the controversial discussion on the relationship between ASC and breast carcinoma cells. Further studies are needed to quantify the in vivo interaction of ASC and mammary carcinoma cells and to conclusively assess the impact of tamoxifen in reconstructive cases with fat grafting.

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.

Systematic review: Oncological safety of reconstruction with fat grafting in breast cancer outcomes

BACKGROUND

Autologous fat grafting (AFG) has become a commonly used procedure for breast reconstruction (BR) after cancer removal. Nevertheless, oncological considerations remain for AFG after breast cancer surgery.

OBJECTIVES

This article aims to evaluate the oncological safety of AFG in BR and its effect on disease-free survival (DFS) and local-regional recurrences (LRR).

METHODS

A systematic review regarding the use of AFG in BR to identify a difference in incidence rates of LRR and DFS between patients who had AFG and controls was performed using PubMed, MEDLINE, Embase, PreMEDLINE, Ebase, CINAHL, PsycINFO, Clinicaltrials.gov, Scopus, and Cochrane databases. The protocol was developed following the Preferred Reporting for Items for Systematic Reviews-Protocols (PRISMA-P) guidelines. The included studies had to match predetermined criteria according to the PICOS approach.

RESULTS

A total of 11 studies were included. Seven studies reported LRR, and 5 studies reported DFS in 5,886 patients. Our systematic review showed that AFG was not associated with increased LRR and DFS. Pooled hazard ratios (HRs) (95% confidence intervals [CIs]) for LRR and DFS were 1.26 (0.90-1.76) and 1.27 (0.96-1.69), respectively.

CONCLUSIONS

AFG can, therefore, be performed safely in BR after breast cancer. Further, randomized controlled trials and related systematic reviews, as well as evidence-based medicine (EBM) studies of level 1, are required to consolidate the results of the studies identified in this systematic review.

Reverse Expansion Following Nipple Sparing Mastectomy: A Natural, Safe and Effective Autologous Technique for Breast Reconstruction

The majority of surgeons choose an implant-based breast reconstruction after mastectomy. Nevertheless, lipofilling is a constantly growing technique allowing a complete breast reconstruction without prosthesis. We introduce our experience using reverse expansion for breast reconstruction following a nipple-sparing mastectomy (NSM) with a subpectoral skin expander. In the period January 2010-August 2021, 106 breast reconstruction procedures were performed on 50 patients after a NSM. We harvested an amount of fat tissue using a 2.5 mm liposuction cannula, we centrifuged it 3 min at 4000 rpm and injected in the recipient site using 3 ml syringes and Coleman cannulas. At the beginning of every session, the breast expander was deflated of a saline volume similar to the one of the fat to be injected. We harvested an average of 679.2 ccs of fat per session and injected an average of 319.3 ccs per breast. The mean number of sessions has been 2.4 per breast. The average number of sessions in a radiotreated patients' subgroup has been slightly higher than a control group. The mean follow-up time was 63.5 months and we observed no complications in 105 over 106 procedures. Lipofilling has proven to be a safe and effective technique for complete breast reconstruction. Our procedure considers the use of a breast expander as a device to prepare the recipient site. Reverse expansion after a NSM allows a like-with-like reconstruction and it might be the first reconstructive choice in a selected group of patients.Level of Evidence IV 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 .

Oncological safety of reconstruction with autologous fat grafting in breast cancer patients: a systematic review and meta-analysis

To evaluate the oncological safety of autologous fat grafting and its effect on disease-free survival and local recurrence in breast cancer patients with autologous fat grafting (AFG) reconstruction. A literature search was performed using the Pubmed, Medline, Web of Science, and Cochrane libraries from January 2011 to March 2020, in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines, to identify all relevant studies involving the application of autologous fat grafting in breast cancer reconstruction procedures. The primary outcome of the meta-analysis was a difference in incidence rates of locoregional recurrence and disease-free survival (DFS) between patients who had autologous fat grafting and controls. A total of 11 studies were included. Eight studies reported local-regional recurrences (LRR) and five studies reported disease-free survival (DFS) in 5,886 patients. Our meta-analysis of all included studies about survival outcomes showed AFG was not associated with increased LRR and DFS. Pooled hazard ratios (HRs) (95% CIs) for LRR and DFS were 1.26 (0.90-1.76) and 1.27 (0.96-1.69), respectively. According to the published literature, autologous fat grafting did not result in an increased rate of LRR and DFS in patients with breast cancer. Autologous fat grafting can, therefore, be performed safely in breast reconstruction after breast cancer.

Oncological Safety of Autologous Fat Grafting in Breast Reconstruction: A Meta-analysis Based on Matched Cohort Studies

BACKGROUND

Autologous fat grafting has become a commonly used procedure for breast reconstruction after breast cancer surgical treatment. Nevertheless, oncological considerations remain concerning autologous fat grafting after breast cancer surgery.

OBJECTIVE

This meta-analysis aimed to summarize the current matched cohort studies and provide high-quality evidence-based conclusions on the oncological safety of fat grafting in breast reconstruction.

METHODS

The Preferred Reporting Items for Systematic Reviews and Meta-analysis guidelines were followed. A literature search was performed on August 1, 2021, using PubMed. All relevant matched cohort studies of patients undergoing autologous fat grafting after breast cancer surgery were included. After independently screening the studies and extracting the data, pooled estimates for local and regional recurrence as well as distant metastases were conducted using Review Manager software (RevMan, version 5.3). Outcomes were expressed as odds ratios and 95% confidence intervals.

RESULTS

Seventeen studies involving 7494 patients were included. The observed outcomes indicated that no significant differences existed in the risks of local and regional recurrence or distant metastases between autologous fat grafting and control groups. Also, there was no significant heterogeneity among the studies.

CONCLUSION

This study provided evidence-based conclusions that support the use of autologous fat grafting in breast reconstruction.

LEVEL OF EVIDENCE III

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 .

The oncological safety of autologous fat grafting: a systematic review and meta-analysis

Objective

To present a systematic review of the literature and a meta-analysis evaluating the oncological safety of autologous fat grafting (AFG).

Summary background data: AFG for breast reconstruction presents difficulties during follow-up radiological exams, and the oncological potential of grafted fat is uncertain. Previous studies confirmed that the fatty tissue could be transferred under a good condition suitable would not interfere with mammographic follow-up, although the issue of oncological safety remains.

Methods

We reviewed the literature published until 01/18/2021. The outcomes were overall survival (OS), disease-free survival (DFS), and local recurrence (LR). We included studies that evaluated women with breast cancer who undergone surgery followed by reconstruction with AFG. We synthesized data using the inverse variance method on the log-HR (log of the hazard ratio) scale for time-to-event outcomes using RevMan. We assessed heterogeneity using the Chi² and I² statistics.

Results

Fifteen studies evaluating 8541 participants were included. The hazard ratios (HR) could be extracted from four studies, and there was no difference in OS between the AFG group and control (HR 0.9, 95% CI 0.53 to 1.54, p = 0.71, I² = 58%, moderate certainty evidence), and publication bias was not detected. The HR for DFS could be extracted from six studies, and there was no difference between the AFG group and control (HR 1.01, 95% CI 0.73 to 1.38, p = 0.96, I² = 0%, moderate certainty evidence). The HR for LR could be extracted from ten studies, and there was no difference between the AFG group and control (HR 0.86, 95% CI 0.66 to 1.12, p = 0.43, I² = 1%, moderate certainty evidence).

Conclusion

According to the current evidence, AFG is a safe technique of breast reconstruction for patients that have undergone BC surgery and did not affect OS, DFS, or LR.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12885-022-09485-5.

Immediate Lipo-Filling as a Novel Technique for Volume Replacement in Oncoplastic Breast Conservative Surgery

BACKGROUND

We aimed to evaluate the feasibility of immediate lipofilling as a volume replacement technique in breast conservative surgery (BCS) in terms of the volume of fat graft resorption after radiotherapy, patient satisfaction, and oncological safety.

PATIENTS AND METHODS

This was a prospective study that included female patients with breast cancer, with small- or medium-sized breasts. The patients underwent BCS followed by lipofilling into the deformed areas away from the tumor site that resulted from direct closure of the tumor cavity. They were followed up for early and late postoperative complications, including recurrence. Volumetric computed tomography was performed before and after radiotherapy to determine percentage fat resorption. Postoperative patient satisfaction was assessed using the Kyungpook National University Hospital Breast Reconstruction Satisfaction Questionnaire.

RESULTS

The study included 54 female patients with a mean age of 47.57 ± 9.26 years. The mean follow-up period was 31.02 ± 4.47 months. Local recurrence was observed in three patients (5.56%). The volume reduction of the injected fat graft ranged from 10.15% to 55.67%, with a mean of 29.27 ± 10.06%. Fifty-two patients (96.30%) reported postoperative satisfaction, and nine of them expressed satisfaction only after a second lipofilling session.

CONCLUSIONS

Immediate lipofilling as a volume replacement technique in BCS is a safe and simple technique without major complications. It has a locoregional recurrence rate similar to BCS alone, with an acceptable fat resorption percentage and high postoperative patient satisfaction.

LEVEL OF EVIDENCE IV

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 .

Autologous Fat Grafting as a Stand-alone Method for Immediate Breast Reconstruction After Radical Mastectomy in a Series of 15 Patients

OBJECTIVE

To date, breast reconstruction after mastectomy essentially uses flap- or prosthetic-based surgery. Autologous fat grafting (AFT) largely used in breast conservative surgery is considered an additional technique in breast reconstruction. The aim of this retrospective study was to report our experience of AFT as a stand-alone method for immediate breast reconstruction.

PATIENTS AND METHODS

Fifteen patients requiring a radical mastectomy underwent AFT for immediate reconstruction since 2014. Previous breast irradiation was not a contraindication. Procedures, complications, and cosmetic results were retrospectively analyzed.

RESULTS

Fifteen patients with an average age of 60.5 (43-78) years were included in this retrospective study. They had a body mass index ranging from 19 to 40. Fourteen had a mastectomy for cancer and 1 for prophylaxis. Nine received breast irradiation (7 before surgery and 2 adjuvant). A mean of 3 (2-6) AFT procedures were required to achieve total breast reconstruction. Except for the first transfer, others were performed as outpatient surgeries. Only 2 minor complications (1 hematoma and 1 abscess) not impairing results were reported. The results after a mean follow-up of 26 months were considered by the patients and surgeon as highly satisfactory even in previously irradiated breast, as assessed using a qualitative scoring analysis.

CONCLUSIONS

Autologous fat grafting as a stand-alone method for immediate breast reconstruction after radical mastectomy is a safe procedure with very consistent results even for patients requiring radiation therapy.

Oncologic safety of breast reconstruction with autologous fat grafting: A systematic review and meta-analysis

BACKGROUND

Autologous fat grating has become increasingly popular as a breast reconstructive procedure. Nevertheless, preclinical studies show that fat transfer to a previous breast cancer site could activate latent cancer cells, creating a favourable environment for disease recurrence. A systematic review and meta-analysis was performed to investigate whether fat grafting increases the risk of locoregional recurrence in patients formerly treated for breast cancer.

METHODS

Based on PRISMA guidelines, a systematic review searching for randomised clinical trials and matched cohorts on the topic was performed in the electronic databases Pubmed, Embase, Web of Science, and Cochrane. The date of the last search was July 20, 2021. The meta-analysis assessed the comparison of locoregional recurrence between groups.

RESULTS

From a total of 558 publications, data from nine matched cohorts (1.6%) reporting on 4247 subjects (1590 and 2657 subjects, respectively, in lipofilling and control groups) were suitable for inclusion in the meta-analysis. Neither of the outcomes had a statistically significant difference for disease recurrence. For the primary outcome, comparing locoregional recurrence rates between groups, the incidence rate ratio was 0.92 (95% CI: 0.68-1.26; P = 0.620).

CONCLUSION

The present meta-analysis, which comprises the outcomes of the individual studies with the best current evidence on the topic so far, strengthens the evidence favouring the oncologic safety of lipofilling for breast reconstruction.

A Role for Adipocytes and Adipose Stem Cells in the Breast Tumor Microenvironment and Regenerative Medicine

Obesity rates are climbing, representing a confounding and contributing factor to many disease states, including cancer. With respect to breast cancer, obesity plays a prominent role in the etiology of this disease, with certain subtypes such as triple-negative breast cancer having a strong correlation between obesity and poor outcomes. Therefore, it is critical to examine the obesity-related alterations to the normal stroma and the tumor microenvironment (TME). Adipocytes and adipose stem cells (ASCs) are major components of breast tissue stroma that have essential functions in both physiological and pathological states, including energy storage and metabolic homeostasis, physical support of breast epithelial cells, and directing inflammatory and wound healing responses through secreted factors. However, these processes can become dysregulated in both metabolic disorders, such as obesity and also in the context of breast cancer. Given the well-established obesity-neoplasia axis, it is critical to understand how interactions between different cell types in the tumor microenvironment, including adipocytes and ASCs, govern carcinogenesis, tumorigenesis, and ultimately metastasis. ASCs and adipocytes have multifactorial roles in cancer progression; however, due to the plastic nature of these cells, they also have a role in regenerative medicine, making them promising tools for tissue engineering. At the physiological level, the interactions between obesity and breast cancer have been examined; here, we will delineate the mechanisms that regulate ASCs and adipocytes in these different contexts through interactions between cancer cells, immune cells, and other cell types present in the tumor microenvironment. We will define the current state of understanding of how adipocytes and ASCs contribute to tumor progression through their role in the tumor microenvironment and how this is altered in the context of obesity. We will also introduce recent developments in utilizing adipocytes and ASCs in novel approaches to breast reconstruction and regenerative medicine.

Comparison of skin sensitivity following breast reconstruction with three different techniques: Autologous fat grafting, DIEP flap and expander/implant1

BACKGROUND

Autologous fat grafting (AFG) has been established over the past two decades as an additive technique during and after breast reconstruction. Complete reconstruction of the breast mound with AFG alone represents an exceptional technique that has been published mostly in case reports or in studies with limited cases.The purpose of this study is to investigate the influence of three different techniques for breast reconstruction on the recovery of skin sensitivity at the reconstructed breast.

METHODS

The study included 30 patients after mastectomy following breast cancer. Three groups were examined: A) breast reconstruction by autologous fat grafting (AFG), B) breast reconstruction by deep inferior epigastric artery perforator flap (DIEP) and C) breast reconstruction by expander/implant (TE).Biometric data were compared; sensitivity tests were performed using Semmes-Weinstein monofilaments.The non-operated, healthy contralateral breasts of the patients were used as a reference.

RESULTS

While the traditional reconstruction techniques by microsurgical anastomosed perforator flap or expander/implant showed a strongly decreased or completely missing sensitivity of the skin, the tests after reconstruction by AFG represented high values of sensory recovery, which came close to the reference group of non-operated breasts.

CONCLUSION

To our knowledge, this is the first study to compare skin sensitivity after AFG-based reconstruction to established techniques for breast reconstruction. We could demonstrate in a limited group of patients, that breast reconstruction by autologous fat grafting can achieve higher values of skin sensitivity compared to traditional techniques.

Safety of autologous fat grafting in breast cancer: a multicenter Italian study among 17 senonetwork breast units autologous fat grafting safety: a multicenter Italian retrospective study

BACKGROUND

Autologous fat grafting (AFG), defined as the re-implant to the breast of fat tissue from different body areas, has been firstly applied to esthetic plastic surgery and then has moved to reconstructive surgery, mainly used for scar correction and opposite breast altering. Nevertheless, due to the potentially unsafe stem-like properties of adipocytes at the tumoral bed level, no clear evidence of the procedure's oncological safety has been clearly documented at present.

PATIENTS AND METHODS

We retrospectively collected data of early breast cancer (BC) patients from 17 Italian Breast Units and assessed differences in terms of locoregional recurrence rate (LRR) and locoregional recurrence-free survival (LRFS) between patients who underwent AFG and patients who did not. Differences were analyzed in the entire cohort of invasive tumors and in different subgroups, according to prognostic biological subtypes.

RESULTS

With a median follow-up time of 60 months, LRR was 5.3% (n = 71) in the matched population, 3.9% (n = 18) in the AFG group, and 6.1% (n = 53) in the non-AFG group, suggesting non-inferiority of AFG (p = 0.084). Building Kaplan-Meier curves confirmed non-inferiority of the AFG procedure for LRFS (aHR 0.73, 95% CI 0.41-1.30, p = 0.291). The same effect, in terms of LRFS, was also documented among different biological subtypes (luminal-like group, aHR 0.76, 95% CI 0.34-1.68, p = 0.493; HER2 enriched-like, aHR 0.89, 95% CI 0.19-4.22, p = 0.882; and TNBC, aHR 0.61, 95% CI 0.12-2.98, p = 0.543).

CONCLUSIONS

Our study confirms in a very large, multicenter cohort of early BC patients that, aside the well-known benefits on the esthetic result, AFG do not interfere negatively with cancer prognosis.

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.

Clinical study of the feasibility, complications, and cosmetic outcomes of immediate autologous fat grafting during breast-conserving surgery for early-stage breast cancer in China

Background

The resection of tumors in small breasts or in areas such as the upper and inner parts of the breast may have disabling cosmetic results. Tumor resection reduces the volume of the breast and may result in asymmetry or distortion of the nipple-areola complex. Autologous fat transfer/grafting has been shown to be a reliable technique for improving these poor cosmetic results. This study aimed to evaluate the feasibility, complications, and cosmetic outcomes of immediate autologous fat grafting during breast-conserving surgery (BCS) in Chinese patients with early-stage breast cancer.

Methods

This retrospective study included 58 patients with early breast cancer treated by the same surgical team from October 2016 to May 2017. The patients were divided into two groups: BCS with lipofilling (experiment group, n=30) and BCS without lipofilling (control group, n=28). All patients received the recommended breast cancer treatment with complementary radiotherapy. The follow-up period after the completion of radiotherapy ranged from 36-44 months. The resected and grafted volumes, complications, esthetic results, patient satisfaction, and recurrence rate within 3 years were compared between the groups.

Results

The average resected and grafted volumes in the lipofilled group were 47 and 74 mL, respectively, with only one seroma and no other complications. Regarding physician evaluation, BCS with lipofilling resulted in better cosmetic outcomes than BCS without lipofilling (33% versus 15%, respectively). Poor responses occurred in only 7% of patients with lipofilling, compared with 15% without lipofilling. Regarding patient self-evaluation, Breast-Q scores including patient satisfaction with their breasts and psychosocial well-being, were significantly higher in patients who received lipofilling compared with non-lipofilled patients. Regional recurrence occurred in one patient (case 21) (3.7%) in the lipofilling group and systemic recurrence occurred in one patient (case 12) (3.8%) in the control group.

Conclusions

Immediate autologous fat grafting is a promising, effective, and convenient technique for partial breast reconstruction after BCS, with potentially higher levels of patient and physician satisfaction compared with traditional BCS.

Trial Registration

Chinese Clinical Trial Registry ChiCTR-ONN-17010514. Registered 24 January 2017.

Autologous fat grafting for breast reconstruction after breast cancer: a 12-year experience

Purpose

The aim of our study was to examine the surgical outcome and complications (efficiency) as well as the incidence of locoregional recurrence and distant metastases (oncological safety) in patients who underwent autologous fat grafting (AFG) of the breast following breast cancer surgery.

Methods

In our monocentric cohort study, retrospective and prospective data were collected from all consecutive patients who underwent AFG after breast cancer between 2008 and 2020; a total of 93 patients met the inclusion criteria.

Results

Our long-term results showed no increase in tumor recurrence and distant metastases in the studied collective when compared to the available literature. We observed 1 local recurrence (1.1%), 2 distant metastases (2.2%), and 1 tumor-related death (1.1%). There was a high degree of patient satisfaction; 67.12% of patients reported adequate satisfaction with autologous fat grafting.

Conclusion

Currently, to our knowledge, this is the study with the longest follow-up time (mean 6.7 years after AFG and 11.5 years after tumor resection). The results of our clinical study will contribute to improve evidence in the broad field of AFG, adipose stem cell and tumor research. Consistent with our study, the literature review shows a clear tendency of clinical trial results with a low incidence rate of tumor recurrence and metastasis following the use of AFG. AFG seems to be a safe procedure also after breast cancer treatment.

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.

Oncologic Safety of Autologous Fat Grafting after Breast Cancer Surgical Treatment: A Matched Cohort Study

BACKGROUND

Autologous fat grafting has been an increasingly popular procedure for remodeling the breast of patients undergoing breast cancer surgery. This study's objective was to investigate whether autologous fat grafting is associated with a higher risk of disease recurrence in the context of late breast reconstruction for patients diagnosed with breast cancer who have undergone either breast-conserving surgery or mastectomy.

METHODS

A retrospective matched cohort study was performed in a single tertiary health care center. Data were collected from 42 patients formerly treated for breast cancer who underwent the first session of autologous fat grafting between August of 2007 and June of 2016. A total of 126 patients with similar features, who did not undergo autologous fat grafting, were individually matched at a 1:3 ratio with the autologous fat grafting group. The primary endpoint was locoregional recurrence. Secondary outcomes were rates of local and distant recurrences, disease-free survival, and overall survival.

RESULTS

At a mean follow-up of 65 months after fat grafting, no significant differences were found between the lipofilling and control groups for locoregional recurrence (7.1 percent versus 6.3 percent; p = 0.856), local recurrence (7.1 percent versus 5.6 percent; p = 0.705), distant recurrence (14.3 percent versus 7.9 percent; p = 0.238), disease-free survival (21.4 percent versus 19.0 percent; p = 0.837), and overall survival (14.3 percent versus 7.1 percent; p = 0.181).

CONCLUSIONS

No evidence of increased risk in any of the survival outcomes was identified. Lipofilling seems to be a safe procedure for breast reconstruction after surgical treatment of breast cancer.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

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.

Lipofilling in Breast Oncological Surgery: A Safe Opportunity or Risk for Cancer Recurrence?

Lipofilling (LF) is a largely employed technique in reconstructive and esthetic breast surgery. Over the years, it has demonstrated to be extremely useful for treatment of soft tissue defects after demolitive or conservative breast cancer surgery and different procedures have been developed to improve the survival of transplanted fat graft. The regenerative potential of LF is attributed to the multipotent stem cells found in large quantity in adipose tissue. However, a growing body of pre-clinical evidence shows that adipocytes and adipose-derived stromal cells may have pro-tumorigenic potential. Despite no clear indication from clinical studies has demonstrated an increased risk of cancer recurrence upon LF, these observations challenge the oncologic safety of the procedure. This review aims to provide an updated overview of both the clinical and the pre-clinical indications to the suitability and safety of LF in breast oncological surgery. Cellular and molecular players in the crosstalk between adipose tissue and cancer are described, and heterogeneous contradictory results are discussed, highlighting that important issues still remain to be solved to get a clear understanding of LF safety in breast cancer patients.

Fat Grafting in Radiation-Induced Soft-Tissue Injury: A Narrative Review of the Clinical Evidence and Implications for Future Studies

SUMMARY

Radiation-induced changes in skin and soft tissue result in significant cosmetic and functional impairment with subsequent decrease in quality of life. Fat grafting has emerged as a therapy for radiation-induced soft-tissue injury, and this narrative review aims to evaluate the current clinical evidence regarding its efficacy. A review was conducted to examine the current clinical evidence of fat grafting as a therapy for radiation-induced injury to the skin and soft tissue and to outline the clinical outcomes that can be used to more consistently quantify chronic radiation-induced injury in future clinical studies. The current clinical evidence regarding the efficacy of fat grafting to treat radiation-induced injury of the skin and soft tissue suggests that fat grafting increases skin softness and pliability, induces volume restoration, improves hair growth in areas of alopecia, reduces pain, and improves cosmetic and functional outcomes. However, literature in this field is far from robust and mired by the retrospective nature of the studies, lack of adequate controls, and inherent limitations of small case series and cohorts. A series of actions have been identified to strengthen future clinical data, including the need for physical examination using a validated scale, appropriate imaging, skin biomechanics and microcirculation testing, and histologic analysis. In conclusion, radiation-induced soft-tissue injury is a significant health burden that can lead to severe functional and aesthetic sequelae. Although still in a preliminary research phase, there is promising clinical evidence demonstrating the benefits of fat grafting to treat chronic changes after radiation therapy. Future clinical studies will require larger cohorts, adequate controls, and consistent use of objective measurements.

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.

Oncologic Safety of Autologous Fat Grafting in Breast Reconstruction

Autologous fat grafting is a useful adjunct to breast reconstruction to address contour changes, volume loss, and deformity. More recent benefits observed include mitigation of pain and inflammation. Although there is no clinical evidence to suggest an increased risk in recurrence or new cancer development in fat grafting for breast reconstruction, the oncologic safety of grafting has come into question. Adipose tissue grafts contain progenitor cells and immunomodulatory cytokines, which may induce vasculogenesis or tumor progression or recurrence at the site. Although these are all theoretical concerns, there is a discrepancy between basic science research and clinical outcomes studies. In this review, the authors summarize available literature regarding three important controversies in fat grafting for oncologic breast reconstruction: the interaction of graft component cells, such as adipose-derived stem cells, with cancer cells; the concern of fat grafting interference with breast cancer screening and detection; and clinical evidence regarding the oncologic safety of fat grafting following breast cancer treatment.

Analysis of oncological safety of autologous fat grafting after immediate breast reconstruction

Background

Fat grafting is now a common procedure for breast reconstruction. Many clinical studies have reported its aesthetic efficacy and oncological safety, but some experimental studies raise about the recurrence risk because of its regenerating property. This study aims to investigate the possibility of cancer recurrence associated with fat grafting.

Methods

In this retrospective cohort study, we analyzed a total of 339 patients who had undergone immediate reconstructive surgery after nipple-sparing mastectomy (NSM) or skin-sparing mastectomy (SSM) in our institution between February 28, 2009 and March 23, 2019. Patients who had undergone breast conserving surgery, radical mastectomy, or delayed reconstruction were excluded. We used univariate and multivariate Cox proportional hazards regression models to evaluate the association between fat grafting and cancer recurrence.

Results

Among the 339 patients during a median follow-up of 52 months, 27 patients (8.0%) were confirmed to have recurrent cancer. Of 67 patients who had undergone fat grafting, 10 patients were confirmed to have cancer recurrence. In multivariate analyses, fat grafting [hazard ratio (HR), 2.52; 95% CI, 1.005-6.317; P=0.0488] was independently associated with cancer recurrence.

Conclusions

In population of breast cancer patient who underwent immediate reconstruction in our institution, fat grafting showed significant higher risk of cancer recurrence. Although these results are at odds with many existing studies, it suggests that more careful follow-up may be necessary for patients who had undergone fat grafting after reconstructive surgery.

Autologous fat grafting in breast reconstruction: implications for follow-up and surveillance

The procedural volume of autologous fat grafting (AFG) has risen over the past several years, specifically in the setting of breast reconstruction, despite controversy surrounding its oncologic safety. While some in vitro and animal models have cast doubt on the oncologic safety of AFG, there is no clinical evidence that AFG in breast reconstruction is associated with an increased risk of cancer development or recurrence or an inability to adequately assess changes in the breast. That being said, recommendations regarding surveillance and follow-up after AFG in breast reconstruction are largely surgeon directed and differ across practices. The purpose of this review is to summarize the current literature and provide evidence-based recommendations.

Is Autologous Fat Grafting an Oncologically Safe Procedure following Breast Conserving Surgery for Breast Cancer? A Comprehensive Review

BACKGROUND

Autologous fat grafting (AFG) is a recognized surgical procedure to correct deformities following breast conservation surgery (BCS) for breast cancer. However, there are concerns about the oncological safety of this technique. In this study we have reviewed the current literature to assess whether AFG adversely influences the oncological outcome after BCS for breast cancer.

METHODS

We have searched the medical literature using the Embase and PubMed search engines from conception until May 2019 to identify all relevant studies of patients who underwent AFG after BCS. Meta-analysis and meta-regression methodologies were used to calculate the overall relative risk (RR) of loco-regional recurrence (LRR) rates for case-control and case series studies (with historical controls) respectively.

RESULTS

We have identified 26 eligible studies with a total of 1640 patients who had undergone fat transfer after lumpectomy for breast cancer. The meta-analysis of 11 studies revealed an overall RR for LRR of 0.82 [95% confidence interval (CI):0.14-1.66]. The meta-regression of case series revealed an overall incidence of LRR of 1.85% compared with 2.53% for historical controls.

CONCLUSIONS

Our study lends further support to the notion that fat transfer after lumpectomy for breast cancer does not seem to increase the risk of LRR. However further prospective research is required in order to confirm this.

The Influence of Fat Grafting on Breast Imaging after Postmastectomy Reconstruction: A Matched Cohort Analysis

BACKGROUND

Fat grafting to the reconstructed breast may result in the development of benign lesions on physical examination, prompting further investigation with imaging and biopsy. The aim of this study was to assess the influence of fat grafting on the incidence of imaging and biopsies after postmastectomy reconstruction.

METHODS

Patients who underwent autologous or implant-based reconstruction following mastectomy from 2010 to 2018 were identified. Those receiving fat grafting as part of their reconstructive course were propensity matched 1:1 to those that did not with body mass index, reconstruction timing, and reconstruction type as covariates in a multivariable logistic regression model.

RESULTS

A total of 186 patients were identified, yielding 93 propensity-matched pairs. Fat-grafted patients had higher incidences of palpable masses (38.0 percent versus 18.3 percent; p = 0.003) and postreconstruction imaging (47.3 percent versus 29.0 percent; p = 0.01), but no significant difference in the number of biopsies performed (11.8 percent versus 7.5 percent; p = 0.32). Imaging was predominately interpreted as normal (Breast Imaging-Reporting and Data System 1, 27.9 percent) or benign (Breast Imaging-Reporting and Data System 2, 48.8 percent), with fat necrosis being the most common finding [n = 20 (45.5 percent)]. No demographic, oncologic, reconstructive, or fat grafting-specific variables were predictive of receiving postreconstruction imaging on multivariate analysis. Fat grafting was not associated with decreased 5-year overall survival or locoregional recurrence-free survival.

CONCLUSIONS

Fat grafting to the reconstructed breast is associated with increased incidences of palpable masses and subsequent postreconstruction imaging with benign radiographic findings. Although the procedure is oncologically safe, both patients and providers should be aware that concerning physical examination findings can be benign sequelae of fat grafting and may lead to increased imaging after breast reconstruction.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Effect of Breast Cancer and Adjuvant Therapy on Adipose-Derived Stromal Cells: Implications for the Role of ADSCs in Regenerative Strategies for Breast Reconstruction

Tissue engineering using Adipose Derived Stromal Cells (ADSCs) has emerged as a novel regenerative medicine approach to replace and reconstruct soft tissue damaged or lost as a result of disease process or therapeutic surgical resection. ADSCs are an attractive cell source for soft tissue regeneration due to the fact that they are easily accessible, multipotent, non-immunogenic and pro-angiogenic. ADSC based regenerative strategies have been successfully translated to the clinical setting for the treatment of Crohn's fistulae, musculoskeletal pathologies, wound healing, and cosmetic breast augmentation (fat grafting). ADSCs are particularly attractive as a source for adipose tissue engineering as they exhibit preferential differentiation to adipocytes and support maintenance of mature adipose graft volume. The potential for reconstruction with an autologous tissue sources and a natural appearance and texture is particularly appealing in the setting of breast cancer; up to 40% of patients require mastectomy for locoregional control and current approaches to post-mastectomy breast reconstruction (PMBR) are limited by the potential for complications at the donor and reconstruction sites. Despite their potential, the use of ADSCs in breast cancer patients is controversial due to concerns regarding oncological safety. These concerns relate to the regeneration of tissue at a site where a malignancy has been treated and the impact this may have on stimulating local disease recurrence or dissemination. Pre-clinical data suggest that ADSCs exhibit pro-oncogenic characteristics and are involved in stimulating progression, and growth of tumour cells. However, there have been conflicting reports on the oncologic outcome, in terms of locoregional recurrence, for breast cancer patients in whom ADSC enhanced fat grafting was utilised as an alternative to reconstruction for small volume defects. A further consideration which may impact the successful translation of ADSC based regenerative strategies for post cancer reconstruction is the potential effects of cancer therapy. This review aims to address the effect of malignant cells, adjuvant therapies and patient-specific factors that may influence the success of regenerative strategies using ADSCs for post cancer tissue regeneration.

Fat grafts enriched with adipose-derived stem cells

Autologous fat grafts are widely used in soft-tissue augmentation and reconstruction. To reduce the unpredictability of fat grafts and to improve their long-term survival, cell-assisted lipotransfer (CAL) was introduced. In this alternative method, autologous fat is mixed and grafted with stromal vascular fraction cells or adipose-derived stem/stromal cells (ASCs). In regenerative medicine, ASCs exhibit excellent therapeutic potential and are also simple to harvest. Although the efficacy of CAL has been demonstrated in experimental and clinical research, studies on its safety in terms of oncologic risk have reported inconclusive results. In order to establish CAL as a viable stem cell therapeutic approach, it will be necessary to demonstrate its oncologic safety in basic and clinical studies. Doing so could transform the paradigm of clinical strategy and practice for the treatment of a wide variety of diseases.

Oncologic Safety and Surveillance of Autologous Fat Grafting following Breast Conservation Therapy

BACKGROUND

Autologous fat grafting is a useful adjunct following breast reconstruction. The impact of autologous fat grafting on oncologic safety and surveillance remains questionable, particularly following breast conservation therapy.

METHODS

The authors performed a retrospective review of patients who underwent delayed fat grafting following breast conservation therapy between 2006 and 2016. A control group of conservatively managed patients without grafting was matched for cancer stage, age, body mass index, and follow-up. Outcomes included locoregional recurrence and oncologic surveillance.

RESULTS

Seventy-two patients were identified per cohort. There were no differences in median age (50 years versus 51 years; p = 0.87), body mass index (28.2 kg/m versus 27.2 kg/m; p = 0.38), or length of follow-up (61.9 months versus 66.8 months; p = 0.144) between controls and grafted patients, respectively. Overall, four patients in each cohort experienced recurrence (5.6 percent; p = 1.00) with similar cumulative incidence estimates observed (log-rank test, p = 0.534). There were no significant differences in palpable mass (9.7 percent versus 19.4 percent; p = 0.1), fat necrosis (34.7 percent versus 33.3 percent; p = 0.86), calcifications (37.5 percent versus 34.7 percent; p = 0.73), or indication for breast biopsy (15.3 percent versus 22.2 percent; p = 0.23) between breast conservation and breast conservation therapy plus autologous fat grafting cohorts, respectively.

CONCLUSIONS

Overall, the authors found no difference in recurrence rates after breast conservation with or without delayed fat grafting. Furthermore, there were no differences in the rates of fat necrosis, palpable mass, and abnormal radiographic findings. This study represents the longest follow-up to date in in a large matched study of autologous fat grafting with breast conservation therapy demonstrating oncologic safety and no interference with follow-up surveillance.

CLINICAL QUESTION/LEVEL OF EVIDENCE

Therapeutic, III.

Application of Fat Grafting in Cosmetic Breast Surgery

The role of fat grafting to the breasts has evolved in the recent past, gaining several new applications within both reconstructive and aesthetic surgery. Initially used for reconstructive purposes to fill lumpectomy defects or to correct residual contour deformities after breast reconstruction, it has since made its way into cosmetic breast surgery and has grown to encompass a wide variety of new indications. Fat grafting in aesthetic breast surgery may be performed as a form of primary autologous breast augmentation or as an adjunct to implant-based breast augmentation to disguise implant edges. It may also be used to provide added volume after explant surgery or to provide improvements in breast contour alongside mastopexy techniques. In this article, we will review the current applications of fat grafting in aesthetic breast surgery and provide an up-to-date summary of its reported outcomes, safety, and complications.

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.

Long-term impact of lipofilling in hybrid breast reconstruction: retrospective analysis of two cohorts

Lipofilling has recently gained popularity as a tool in primary treatment of breast cancer, and its association with two-stage implant breast reconstruction is considered as standard treatment in many centers. However, no data are available about the long-term results of the association of lipofilling in combination with expander-implant reconstruction. A retrospective analysis was conducted on patients treated between January 2010 and December 2014. Two groups were compared. Group 1 had a standard expander-implant two-stage reconstruction. Group 2 underwent hybrid breast reconstruction (HBR). Patient characteristics, hospitalization, outcomes, reoperation details, outpatient visits, and evaluation questionnaires were taken into consideration. Intergroup comparison was performed using Wilcoxon Mann-Whitney U test and Pearson’s chi-square test or Fisher’s exact test for categorical variables. Two hundred fourteen patients were evaluated: 130 patients in group 1 and 84 patients in group 2. Group 2 showed significant benefits over group 1 in terms of capsular contracture rate, breast pain, and displacement/rotation of the implant (p = 0.005). The HBR protocol is associated with lower rate of capsular contracture, less breast pain at long follow-up times, and lower overall rates of revision surgery compared to standard expander-implant reconstruction. A specific cost analysis will help further clarify the advantages of this protocol over a standard procedure.

Level of Evidence: Level III, risk/prognostic, therapeutic study.

Long-term Follow-up of Autologous Fat Transfer vs Conventional Breast Reconstruction and Association With Cancer Relapse in Patients With Breast Cancer

Importance

Autologous fat transfer (AFT or fat grafting) has become an invaluable tool for the correction of disfiguring deformities after breast cancer surgery. However, clinical and animal studies have shown conflicting results regarding its oncologic safety.

Objective

To determine whether exposure to AFT vs conventional breast reconstruction is associated with increased rates of cancer relapse in patients with breast cancer.

Design, Setting, and Participants

This matched cohort study involved retrospective medical record review to identify all patients in a local patient database receiving AFT between 2006 and 2014. Each AFT case was matched with a nonexposed control patient with similar baseline characteristics. The mean (SD) follow-up of patients receiving AFT was 9.3 (4.9) years including 5.0 (1.7) years following AFT. Control patients were followed up for a mean (SD) of 8.6 (1.8) years from the primary surgery. Patients were identified through the local patient database of the Tergooi Hospital in Hilversum, the Netherlands. A total of 287 patients with breast cancer (300 affected breasts) who received AFT for breast reconstruction after cancer were included in the intervention group. Each AFT case was matched with a respective control patient based on age, type of oncologic surgery, tumor invasiveness, and disease stage. In addition, individual AFT-control pairs were selected to have the same locoregional recurrence-free interval at baseline. Data were analyzed between 2016 and 2017.

Exposures

Reconstruction with AFT vs conventional breast reconstruction or none.

Main Outcomes and Measures

Primary end points were the cumulative incidences of oncologic events in AFT and control patients and their respective hazard ratios.

Results

Of the 587 total patients, all were women and the mean age was 48.1 years for the patients undergoing AFT and 49.4 years for the control patients. Eight locoregional recurrences were observed in the treatment group (287 patients) and 11 among the control group (300 patients), leading to an unadjusted hazard ratio of 0.63 (95% CI, 0.25-1.60; P = .33). No increased locoregional recurrence rates were seen in relevant subgroups based on the type of oncological surgery, tumor invasiveness, or pathological stage. In addition, no increased risks with AFT were detected with respect to distant recurrences or breast cancer-specific mortality.

Conclusions and Relevance

No significant differences in the locoregional recurrence rates between the AFT and control groups were observed after 5 years of follow-up. These findings confirm the results of previous studies; therefore, clinical evidence suggesting that AFT is associated with increased risk for cancer relapse is still lacking.

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.

Does Choice of Reconstruction Type Affect Survival in Patients With Metastatic Breast Cancer?

BACKGROUND

To compare the breast cancer-specific survival (BCSS) and overall survival (OS) between patients who underwent implant or tissue reconstruction after mastectomy with distant metastatic breast cancer (MBC).

MATERIALS AND METHODS

Using the Surveillance, Epidemiology, and End Results database, we enrolled 371 female MBC cases diagnosed during the years 2004-2014. Patients were subdivided into implant (176) and tissue groups (195) for survival comparison between the two groups. The end points were BCSS and OS. Comparisons of the distribution of clinicopathologic characteristics were evaluated by chi-square test and Fisher exact test. Survival outcomes were compared by Kaplan-Meier model and multivariate Cox regression model for known clinicopathologic variables in both the entire population and in the reconstruction cohorts.

RESULTS

In the entire cohort, patients with implant exhibited distinctly better BCSS (log rank, P = 0.002) and OS (log rank, P = 0.001) than patients with tissue reconstruction. Multivariate Cox regression model revealed that patients, who received prosthetic implants, were married, and progesterone receptor-positive group showed better survival rates in BCSS and OS. In addition, after stratification of the implant group and tissue groups according to clinicopathologic variables, the survival rate of patients in the implant group was higher than that in the tissue reconstruction group under the influence of factors, such as married, estrogen receptor-negative, nonradiotherapy, and chemotherapy.

CONCLUSIONS

Our study provides further survival evidence supporting the practice of mastectomy with prosthetic implant reconstruction in patients with MBC under certain conditions.

International Expert Panel Consensus on Fat Grafting of the Breast

Background

Autologous fat grafting has broad applications in reconstructive and aesthetic breast surgery as a natural filler and for its regenerative purposes. Despite the widespread use of fat grafting, there remains no shared consensus on what constitutes the optimal fat grafting technique and its oncological safety. For this reason, the authors of this study have organized a Survey and an International Consensus Conference that was held at the Aesthetic Breast Meeting in Milan (December 15, 2018).

Methods

All studies on fat grafting, both for breast aesthetic and reconstructive purposes, were electronically screened. The literature review led to 17 "key questions" that were used for the Survey. The authors prepared a set of 10 "key statements" that have been discussed in a dedicated face-to-face session during the meeting.

Results

The 10 key statements addressed all the most debated topics on fat grafting of the breast. Levels of evidence for the key statements ranged from III to IV with 2 statements (20%) supported by a level of evidence III and 6 statements (60%) by level of evidence IV. Overall consensus was reached for 2 statements (20%) with >75% agreement reached for 7 statements.

Conclusions

The survey demonstrated a diversity of opinion and attitude among the panelists with regard to technique. Clear recommendations for evidence-based clinical practice for fat grafting use both in aesthetic and reconstructive breast surgery could not be defined due to the scarcity of level 1 or 2 studies.

Autogenous Fat Grafting to the Breast and Gluteal Regions: Safety Profile Including Risks and Complications

Given the widespread utility and therapeutic potential of autogenous fat grafting, plastic surgeons should be familiar with its safety profile and associated adverse events. This article provides a critical review of the literature and delineates risk factors associated with various complications when grafting to the breast and gluteal regions. The majority of adverse events are related to fat necrosis and require minimal diagnostic or therapeutic intervention. Larger graft volumes, as in cosmetic augmentation, are associated with higher incidences of fatty necrosis. The oncologic safety of fat grafting is supported by multiple clinical studies with thousands of breast cancer patients, albeit predominantly retrospective in nature. Although less frequent, serious complications include fat emboli during gluteal augmentation. Identification of associated risk factors and implementation of proper surgical techniques may minimize the occurrence of life-threatening complications.

Autologous fat transfer after breast cancer surgery: An exact-matching study on the long-term oncological safety

INTRODUCTION

Autologous fat transfer (AFT) is widely adopted for breast reconstruction, but its long-term oncologic safety is still not clearly established. The aim of the present study was to compare the 10-year loco-regional recurrence (LRR)-free and distant metastases (DM)-free survival probabilities in AFT vs. control patients, also evaluating the impact of AFT in different intrinsic molecular subtypes of breast cancer.

MATERIALS AND METHODS

464 AFT patients were exactly matched with a cohort of 3100 control patients treated between 2007 and 2017. A multivariate survival analysis was performed accounting for all variables related to LRR and DM, including adjuvant/neoadjuvant treatments. End-points were analyzed both overall and in each molecular subtype.

RESULTS

LRR occurred in 6.4% of AFT and in 5.0% of control patients (p = 0.42), while DM were observed respectively in 7.7% and 5.4% of cases (p = 0.20). AFT showed no effect on the 10-year LRR-free survival probability (adjusted HR 0.87, 95%CI 0.43-1.76, p = 0.69) or the 10-year DM-free survival probability (adjusted HR 0.82, 95%CI 0.43-1.57, p = 0.55). Luminal A patients treated by AFT showed a decreased LRR-free survival probability (HR 2.38, 95%CI 0.91-6.17, Log-Rank p = 0.07), which was significantly lower than controls after 80 months (Log-Rank p = 0.02). No differences in the 10-year event-free survival probability were found in Luminal B, HER2-positive or triple-negative patients.

CONCLUSION

AFT does not increase breast cancer recurrence, with the possible exception of late LRRs for Luminal A patients, but further clinical and preclinical data are required to better clarify this data. The use of AFT should not be discouraged.