Background:
Post-mastectomy radiation is commonly employed in the treatment of breast cancer despite possible deleterious effects on breast reconstruction outcomes. High variability in post-radiation complications demonstrates further investigation is necessary to recognize factors contributing to adverse results. The purpose of this study is to (1) accurately assess the impact of radiation on autologous breast reconstructions in our population and (2) attempt to identify patient and treatment factors affecting reconstructive outcomes.
Methods:
915 women were identified who underwent breast reconstruction following mastectomy between 1999 and 2008. Of these, 126 patients received breast reconstruction followed by radiation. The records of 76 patients were studied after excluding for: radiation therapy prior to reconstruction, complications before radiation, implant reconstruction, mastectomy for disease recurrence, or prior history of cancer. Patient demographics and comorbidities, operative details, adjuvant therapy, and treatment outcomes were assessed. Primary outcomes included: complete or partial flap loss, fat necrosis, fibrosis/soft tissue envelope retraction, revisions, excessive pain, hyper-pigmentation, and patient/physician dissatisfaction. Associations between demographic, surgical, and treatment variables with the occurrence of a complication are reported as odds ratios with associated p-values using logistic regression.
Results:
For 76 autologous microsurgical breast reconstruction patients, the mean age was 47.1+/-10.7(mean+/-SD) years and BMI was 27.2+/-5.9kg/m2. Post-radiation complications were noted in 53 patients (70%) requiring revisions in 36 cases (48%). The study included 60 (79%) free TRAM, 3 gracilis (4%), 4 SGAP (5%), 3 DIEP (4%), and 6 SIEA (8%) procedures. The average radiation dose received was 5023+/-660 cGy (mean+/-SD) with a mode fraction size of 180cGy (range 170-200 cGy). Neo-parenchymal complications (fat necrosis or parenchymal fibrosis) were noted in 19.7%, skin complications (tissue envelope retraction or hypertrophic scarring) were recorded in 30.2%, and general dissatisfaction (excessive pain or physician/patient dissatisfaction) arose in 27.6% of all patients following radiation therapy. Parenchymal complications were associated with smoking (Odds Ratio 9.3, p=0.03), diabetes (8.5, 0.02), and age (1.1, 0.02). Regarding treatment factors, neoadjuvant chemotherapy increased the development of complications (4.365, 0.04), particularly skin changes (2.392, 0.01). The probability of a surgical revision increased following the development of a complication (5.984, 0.01) with parenchymal changes contributing to high revision rates (4.582, 0.004). Lastly, the average age of subjects who developed skin complications (46.33+/-10.7 years) tended to be lower than that of patients without healing difficulties (51.22 +/-10.4 years), p=0.08.
Conclusions:
The use of post-mastectomy radiation is associated with a significant complication rate in our patients undergoing autologous reconstruction. Patient specific factors, including diabetes and smoking, increase the risk of post-radiation parenchymal changes while neoadjuvant chemotherapy is associated with over a 2-fold increase in skin complications and nearly a 5-fold rise in any complication measured. Minimal variability in the amount of radiation received between patients indicates deleterious outcomes are unlikely due to aspects of radiation therapy. Breast reconstruction followed by radiation can be successful, but should be approached with caution and anticipation of complications in patients with specific risks.