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Outlier: a scientific term to describe things or phenomena that lie outside normal experience.Drs. Glasberg and Light report their experience using two different types of acellular dermal matrices for tissue expander breast reconstruction. The article details both patient outcomes and technical details for the use of these products, and concludes that the consistent outcomes seen with these products justify their continued use and outweigh their initial cost. However, comparison of the data in this article both to the literature and to our institutional experience reveals that the results of this study lie outside collective experience for this procedure.A recently published meta-analysis of tissue expander breast reconstruction outcomes reported a 4.9 percent skin flap necrosis rate for 12,847 submuscular expanders and a 6.9 percent flap necrosis rate for 2037 acellular dermal matrix expander reconstructions.1 Glasberg and Light reported skin flap necrosis in only two of 270 patients, for a rate of 0.7 percent, only one-tenth the rate reported in the literature. Demographically, the patients in this study are comparable to those in the meta-analysis, with expected rates of smokers and diabetics and a comparable median age. The authors attribute their low flap necrosis rate to those in conservative intraoperative filling of the expander—enough to decrease seromas by opposing the acellular dermal matrix to the skin flap, but not so much as to contribute to tissue necrosis. The authors go on to write that full expansion was achieved after only two fills (on average) in the office, and do not provide tissue expander volumes, intraoperative fill volumes, or postoperative fill volumes. Therefore, by inference and in the absence of data, one is led to surmise that the implants are actually filled quite aggressively in the operating room. The use of acellular dermal matrix in tissue expander breast reconstruction should increase the rate of flap loss, as the acellular dermal matrices permit the greater filling of the implant and therefore cause greater skin tension and potential hypoperfusion. This concept is supported by the meta-analysis data, and yet the authors' skin flap loss rate is extremely low. Looking at other possibilities, perhaps there are other maneuvers performed by the authors to avoid skin flap loss. The majority of the technical tips provided in the article are aimed at the prevention of infection and would not reasonably influence the mastectomy skin flap loss rate. An alternative explanation for the data could relate to the authors' definition of “flap necrosis,” which is not provided in the article and may not include marginal wound healing treated in the office with dressings or reexcision and closure.It is noteworthy that 76 patients in this study received radiation therapy either before (n = 28) or after (n = 48) their tissue expander insertion. In the majority of the current literature2 and in our own institutional experience,3 radiation is associated with a significant increase in complications and an implant loss/nonelective conversion to flap rate of between 20 and 30 percent.4 Consequently, some centers will not place permanent implants in this setting,5 and others will alter the timing of their reconstructive sequence6 or postoperative management7 to potentially minimize complications. However, complications are so low in this series that the radiation-related complications are not even treated separately. The authors report only five expander losses, not just for the irradiated cohort, but for the entire series. In addition, the authors report only five instances of capsular contracture and do not report a single case of implants that were removed for issues of tightness, malposition, or dissatisfaction with cosmesis of the irradiated chest.