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

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.

The effect of obesity on adipose-derived stromal cells and adipose tissue and their impact on cancer

The significant increase in the incidence of obesity represents the next global health crisis. As a result, scientific research has focused on gaining deeper insights into obesity and adipose tissue biology. As a result of the excessive accumulation of adipose tissue, obesity results from hyperplasia and hypertrophy within the adipose tissue. The functional alterations in the adipose tissue are a confounding contributing factor to many diseases, including cancer. The increased incidence and aggressiveness of several cancers, including colorectal, postmenopausal breast, endometrial, prostate, esophageal, hematological, malignant melanoma, and renal carcinomas, result from obesity as a contributing factor. The increased morbidity and mortality of obesity-associated cancers are attributable to increased hormones, adipokines, and cytokines produced by the adipose tissue. The increased adipose tissue levels observed in obese patients result in more adipose stromal/stem cells (ASCs) distributed throughout the body. ASCs have been shown to impact cancer progression in vitro and in preclinical animal models. ASCs influence tumor biology via multiple mechanisms, including the increased recruitment of ASCs to the tumor site and increased production of cytokines and growth factors by ASCs and other cells within the tumor stroma. Emerging evidence indicates that obesity induces alterations in the biological properties of ASCs, subsequently leading to enhanced tumorigenesis and metastasis of cancer cells. As the focus of this review is the interaction and impact of ASCs on cancer, the presentation is limited to preclinical data generated on cancers in which there is a demonstrated role for ASCs, such as postmenopausal breast, colorectal, prostate, ovarian, multiple myeloma, osteosarcoma, cervical, bladder, and gastrointestinal cancers. Our group has investigated the interactions between obesity and breast cancer and 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 (TME) are discussed. The reciprocal and circular feedback loop between obesity and ASCs and the mechanisms by which ASCs from obese patients alter the biology of cancer cells and enhance tumorigenesis will be discussed. At present, the evidence for ASCs directly influencing human tumor growth is somewhat limited, though recent clinical studies suggest there may be some link.

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.