Interval inset of TRAM flaps in immediate breast reconstruction: a technical refinement

Healthy, viable mastectomy skin is a critical factor in the outcome of immediate breast reconstruction. Unfortunately, mastectomy skin viability can be problematic and intraoperative assessment is unreliable. For this reason, we have modified our approach to immediate transverse rectus abdominus myocutaneous flap (TRAM) reconstruction. Instead of completing the reconstruction with a definitive inset at the time of the mastectomy, the TRAM flap is left intact and buried beneath the mastectomy skin for 3 to 5 days. This falls within the normal period of postoperative hospitalization, and at this point, the viability of the mastectomy skin is clear. Ischemic skin is debrided and replaced with healthy TRAM skin, and nipple reconstruction can be performed at the time of this interval inset. The purpose of this study was to review a large case series of patients who underwent an interval inset of their TRAM flap in the setting of immediate skin-sparing mastectomy.

Retrospective chart data were obtained for all TRAM patients who underwent immediate postmastectomy breast reconstruction by a single surgeon during a 5-year period. Data were collected on procedures, complications, margin status, and number of immediate versus delayed nipple reconstructions.

There were 63 patients who underwent immediate TRAM reconstruction with interval inset of the flap. This included 25 bilateral cases, for a total of 89 flaps. Interval insets were performed an average of 3.9 days after the TRAM. Twenty-seven percent (17/63) required replacement of nonviable mastectomy skin with TRAM skin and had no nipple reconstruction; 4.8% (3/63) had additional skin taken because of residual tumor close to or at the mastectomy margins. Seventy-three percent of patients (46/63) had a nipple reconstruction with minimal or no mastectomy skin loss.

We present the interval inset of TRAM flaps during the normal period of postoperative hospitalization as a technical refinement to optimize cosmetic outcomes. Mastectomy skin viability can be more easily assessed and necrotic or ischemic skin replaced with TRAM skin as needed. This avoids the need for prolonged dressing changes or a compromised aesthetic result from skin loss. When there is no major skin loss, the nipple reconstruction can be performed concurrently with the inset. These refinements optimize the appearance of the reconstructed breast and reduce the need for future surgeries. In addition, the surgical oncologist has the opportunity to excise close or positive margins as indicated by pathologic findings. Thus, the benefits of the interval inset of TRAM flaps are shared by the reconstructive surgeon, the surgical oncologist, and most importantly, the patient.