Autologous fat grafting to the breast is becoming an increasingly popular technique in plastic surgery. Fat is aspirated from the trunk or thighs and injected into the breast for augmentation or correction of contour deformities after breast conservation therapy or postmastectomy reconstruction. Although the technique shows great promise, transfer of fat cells to the breast has a theoretical risk of promoting tumor recurrence through several plausible mechanisms. Adipose cells produce hormones and cytokines associated with breast tumor growth, and adipose-derived stem cells potentiate tumor cell growth in in vitro and animal models. Evaluating the risk of recurrence due to fat grafting is challenging because the outcome (recurrence) is relatively rare and has a long time horizon, and the exposure (fat grafting) is difficult to measure and began only recently. Thus, prior studies have been limited by inadequate sample sizes, heterogeneous patient populations, and short follow-up periods or failure to adjust for variable follow-up periods. Despite these challenges, plastic surgeons and patients have a current and strong need for information on the safety of this procedure. We propose a retrospective case-cohort study with the following specific aim: Evaluate the relative risk of breast cancer recurrence after autologous fat grafting to the breast, in a hospital-based population of early stage (I-IIIa) breast cancer patients who have mastectomy with immediate reconstruction. Our hypothesis is that the risk of locoregional or distant recurrence will be higher in patients who have had fat grafting, relative to patients who have had no fat grafting. Cases will be patients who have developed local, regional, or distant breast cancer recurrence during the study period (2006 to 2011), and controls will be a random sample of patients without recurrence. Data will be collected from MD Anderson Cancer Center, Memorial Sloan Kettering Cancer Center, Washington University, and University of Chicago, and study coordination will take place at the University of North Carolina. The cancer registry at each site will identify cases and controls, and a research assistant at each site will review patients’ medical records to identify exposure to fat grafting. Time-to-event analysis, which adjusts for variable length of follow-up, will be used to estimate the ratio of the risk of recurrence among patients who had fat grafting compared to those who did not have fat grafting. Results will contribute to the design of a larger and more precise study, which will benefit from a longer period having elapsed since the onset of the practice of fat grafting. The current study is designed to produce a timely and valid estimate of the risk of cancer recurrence associated with fat grafting, for dissemination to plastic surgeons in two years.
|Effective start/end date||7/1/12 → 12/31/15|
- The Plastic Surgery Foundation (PSF) (Plastic Surgery Educational Foundation (PSEF))
Neoplastic Stem Cells