Background: More breast cancer patients are undergoing post-mastectomy radiation based on reports of improved lorcoregional control and survival. Although immediate TRAM breast reconstruction yields favorable aesthetic results, delaying the reconstruction until completion of radiotherapy spares the flaps from unpredictable fibrosis. It remains unclear whether the thoracodorsal (TD) or the internal mammary (IM) vessels are the preferred recipient vessels, considering the effects of radiation and scarring from previous surgery.

Purpose: To compare the TD and IM vessels as recipient sites for usability rates and outcomes in a uniform group of patients undergoing TRAM flaps in a delayed fashion after post-mastectomy radiotherapy.

Methods: Between 1990 and 2001, 159 consecutive delayed, irradiated TRAM flap patients were identified from a prospective database. Charts were reviewed for recipient vessel choice, inspection and decline of any recipient vessel, and outcomes including flap failure, vascular complications, fat necrosis and lymphedema. T- tests, chi-squared and multivariate analyses were performed to compare vessel choice and outcome.

Results: During this period, 123 of 159 patients were planned as a free flap, of which 106 were able to be performed as a free flap. The remaining 17 were converted to a pedicle TRAM due to unusable recipient vessels. Of the free flaps, 45 were anastomosed to the IM’s, 55 to the TD’s and 6 to other vessels. The IM and TD group were well matched for BMI, smoking history, # of scars in the flap, time between XRT and reconstruction, and ischemia time. 26% of TD, and 20% of IM vessels were unusable as recipients (p=0.42). Excluding the IM vessels deemed unusable by preoperative duplex doppler examination, the number of IM vessels declined on intraoperative dissection and inspection decreased to 12% (p=0.056). Of the unusable TD’s, 84% were too scarred, 11% were too small and 5% were absent. Of unusable IM’s, 46% had unusable veins, 27% had unusable arteries and 27% had both. The unusability rate for IM vessels was equivalent for left- and right-sided reconstructions (23% vs 17%, p=0.55). Outcomes were similar regardless of recipient vessel used (TD vs IM): flap loss (3.6% vs 0%, p=0.20), partial flap failure (5.5% vs 8.9%, p=0.54), vascular complications (11% vs 7%, p=0.46), fat necrosis (15% vs 18%, p=0.69), lymphedema (9% vs 4%, p=0.37). Logistic regression revealed a trend toward higher overall complication rate with use of TD vessel (OR 2.8, p=0.19)

Conclusion: TD and IM recipient sites allowed for similar usability and outcome.