Does post-mastectomy radiotherapy affect the outcome and prevalence of complications in immediate DIEP breast reconstruction? A prospective cohort study.

INTRODUCTION: The decision to perform immediate deep inferior epigastric perforator (DIEP) flap reconstruction in patients requiring post-mastectomy radiation therapy (PMRT) is controversial, and often influenced by the increased potential of complications. We assessed the outcome and complications of irradiated immediate DIEP-reconstructed flaps in a two-surgeon series in our department.

METHODS: Data collected prospectively from all patients undergoing immediate DIEP reconstruction under the two senior authors' care over 24 months were reviewed. Patients receiving previous radiation were excluded. Included patients were divided into two groups - requiring or not requiring PMRT. Primary outcome measures were fat necrosis, surgery for removal of fat necrosis, volume loss requiring surgery, wound complications and flap survival. All patients with a clinical diagnosis of post-radiation fat necrosis had an ultrasound scan.

RESULTS: The series included 112 patients with a total of 156 flaps (44 bilateral, 68 unilateral). In 61/156 flaps the patients received PMRT (Group A) whilst 95/156 did not (Group B). Demographics in both groups were similar. Outcomes in PMRT vs. no PMRT, respectively were: fat necrosis 11.5% vs. 6.35% (p = 0.199); surgery for removal of fat necrosis 6.6% vs. 4.2% (p = 0.383); volume enhancement surgery 4.9% vs. 5.2% (p = 0.617); minor wound healing delay, 3.2% vs. 7% (p = 0.433); major wound healing delay 2.5% vs. 5.7% (p = 0.558). 0/61 flaps were lost in group A and 2/95 in group B.

CONCLUSION: Although studies have shown the deleterious effects of post-operative radiotherapy on breast free flaps, our department offers immediate breast reconstruction with the acceptance of the risk/benefit profile. We found no increase in complication rates in patients undergoing immediate DIEP reconstruction receiving PMRT, and the outcome was not adversely affected. As part of an ongoing study, we do not feel that post-mastectomy radiotherapy precludes the decision for immediate free-flap breast reconstruction.