© 2005 Blackwell Publishing, Inc., 1075-122X/05 The Breast Journal, Volume 11 Number 3, 2005 199– 203 Address correspondence and reprint requests to: Alan Stolier, MD, FACS, Tulane Medical School, Dept. of Surgery £SL22, 1430 Tulane Ave., New Orleans, LA 70112, USA, or e-mail: astoli@lsuhsc.edu. Blackwell Publishing, Ltd. ORIGINAL ARTICLE Postlumpectomy Insertion of the MammoSite Brachytherapy Device Using the Scar Entry Technique: Initial Experience and Technical Considerations Alan J. Stolier, MD,* George M. Fuhrman, MD, † Troy G. Scroggins, MD, † and Cynthia I. Boyer, MD † *Department of Surgery, Tulane University and the Tulane Cancer Center, and † Ochsner Clinic Foundation, New Orleans, Louisiana  Abstract: For women undergoing breast-conserving surgery, recent reports suggest that in selected cases accelerated par- tial breast irradiation may yield results equal to that of whole breast irradiation. Over 31 months, 19 patients underwent accelerated partial breast irradiation using the MammoSite as the sole radiation treatment following breast-conserving surgery. Seventeen patients had the MammoSite inserted postoperatively using the scar entry technique (SET). Treatments were delivered using high dose rate iridium 192 given twice a day for 5 days. Three complications (two minor, one major) occurred. Late radiation morbidity and overall cosmetic results were evaluated. Eighty percent of patients had either no change from baseline or slight change in skin pigment. More than 90% had good or excellent overall cosmetic outcomes. Patients undergoing accelerated partial breast irradiation with the MammoSite inserted using SET had excellent overall cosmetic results. Advantages of the SET over intraop- erative placement are presented.  Key Words: breast cancer, brachytherapy, radiation, surgery, treatment W hole breast irradiation following lumpectomy has become the standard treatment for women choos- ing breast conservation (1,2). This therapy is able to treat undetected foci of cancer not removed during surgical excision. More recently, however, several reports of accel- erated partial breast irradiation have suggested that in many instances whole breast radiation may not be neces- sary (3–5). Currently the options for accelerated partial breast irradiation include three-dimensional conformal external beam and brachytherapy either with interstitial catheters or, more recently, utilizing the MammoSite device (Proxima Therapeutics, Alpharetta, GA). Place- ment of the MammoSite device can be accomplished at the time of lumpectomy or during the postoperative period. We chose to examine our initial experience with the MammoSite catheter in patients in whom it was the sole radiation modality and in whom the catheter was inserted in the postoperative period by the scar entry tech- nique (SET). METHODS Scar Entry Technique Within the first 1–2 weeks after breast-conserving sur- gery, ultrasound of the lumpectomy cavity is carried out in order to determine if the cavity is of appropriate size and shape to hold the MammoSite, and to determine whether there is an adequate bridge of tissue between the lumpec- tomy cavity and the skin (skin bridge) (Fig. 1). To protect the skin from excessive radiation, an attempt was made to provide a skin bridge of at least 1 cm of breast or fibrofatty tissue. The minimum accepted skin bridge was 5 mm. Insertion of the device is carried out in the outpatient clinic setting under local anesthesia without sedation. Ultra- sound is generally performed just prior to insertion and the cavity is rechecked for appropriate size, shape, and cavity-to-skin distance. The cavities were measured in three dimensions. Cavities that measured more than 4 cm in two dimensions were considered too large for the 4 – 5 cm MammoSite balloon. (Subsequent to this study, a 5 – 6 cm MammoSite balloon has become available.) A minimal balloon-to-skin distance was 5 mm, although 7 mm was more desirable. A 1–1.5 cm area of skin is anesthetized and 10 cc of 1% xylocaine is instilled into the lumpectomy cavity Address correspondence and reprint requests to: Alan Stolier, MD, FACS, Tulane Medical School, Dept. of Surgery £SL22, 1430 Tulane Ave., New Orleans, LA 70112, USA, or e-mail: astoli@lsuhsc.edu.