A New Method for Partial Breast Reconstruction: 3-Year New Zealand Experience.

In New Zealand, oncoplastic surgery is common, but partial breast reconstruction presents challenges for radiation therapy targeting. Tissue rearrangement creates ambiguity when targeting the tumor bed, with resultant overestimation of treatment volumes. Thus, adoption of advanced methods of radiation therapy have been hindered. This pilot study describes use of a novel three-dimensional implant that provides a scaffolding for tissue ingrowth during partial breast reconstruction and delineates the tumor bed more precisely to assist radiation planning and mammographic surveillance. After informed consent, 15 women were implanted with the three-dimensional bioabsorbable implant. The device was sutured to the tumor bed during lumpectomy, and tissue flaps were mobilized and attached to the implant. Visualization of the marker and radiation treatment volumes were recorded and compared. The implant provided volume replacement and helped to maintain breast contour. Cosmetic outcomes were excellent; no device- or radiation-related complications occurred. One patient had a postoperative hematoma that resolved after percutaneous drainage; there were no postoperative infections. Three-year follow-up shows no tumor recurrences and no untoward effects. When compared to conventional radiation targeting, use of the implant showed that a greater than 50 percent reduction in treatment volume was possible in some cases. Three-year mammograms show no significant artifact, normal tissue ingrowth, and minimal fibrosis. This study describes a method of oncoplastic breast reconstruction using an implantable device that marks the site of tumor excision and provides for volume replacement with tissue ingrowth. Patients tolerated it well, and radiation therapy planning, positioning, and treatment were facilitated.