Toxicity and cosmetic outcomes after treatment with a novel form of breast IORT.

PURPOSE: Intraoperative radiation therapy (IORT), a form of accelerated partial breast irradiation (APBI), is an appealing alternative to postoperative whole breast irradiation for early-stage breast cancer. The purpose of this study was to examine the toxicity and cosmetic outcomes of patients treated with a novel form of breast IORT (precision breast IORT; PB-IORT), that delivers a targeted, higher dose of radiation than conventional IORT. METHODS AND MATERIALS: The first 204 patients treated with PB-IORT in a Phase II clinical trial (NCT02400658) with 12 months of followup were included. Trial inclusion criteria were age ≥45 years, invasive or in situ breast cancer, tumor size ≤3 cm, and node negative. Toxicity and cosmetic scoring were performed at 6 and 12 months. RESULTS: 98 patients (48%; 95% CI, 41-55%) experienced toxicity. Seven Grade 3 toxicities occurred (3.4%; 95% CI, 1.4-6.9%). Most patients (95%) had excellent or good cosmetic outcomes (95% CI, 91-98%) at 12 months. Most patients (94%) had little or no pigmentation change (95% CI, 90-97%), 88% little to no size change (95% CI, 82-92%), and 87% experienced minimal shape change (95% CI, 82-92%). CONCLUSIONS: Overall, Grade 3+ toxicity was rare and cosmetic outcomes were excellent. Severe toxicity with PB-IORT is similar to that reported in the TARGIT trial (3.3% rate of major toxicity) but lower than APBI (NSABP-39, 10.1% Grade 3/4 toxicities). We propose that the toxicity of PB-IORT compared with TARGIT and NSABP-39 is related to the radiation dose and delivery schedule. PB-IORT offers low-toxicity and good cosmetic outcomes when compared with other forms of APBI.

Extended Prophylactic Antibiotics for Mastectomy with Immediate Breast Reconstruction: A Meta-analysis.

The risk of surgical site infection (SSI) for breast surgery in patients without additional risk factors is low, below 5%. Evidence shows the risk of SSI is significantly elevated in patients undergoing immediate breast reconstruction (IBR). However, there is no consensus regarding the use of extended antibiotic prophylaxis. We aim to determine the effect of extended antibiotic prophylaxis on the incidence of SSI after IBR. METHODS: PubMed and Scopus were searched by 2 independent reviewers. Data abstracted included types of study, basic characteristics, detailed antibiotic prophylaxis information, SSI event, and other secondary outcomes. We calculated the risk ratio (RR) and 95% confidence interval (CI) for each study and used a random-effects model to estimate the results. Study quality, bias, and heterogeneity were also analyzed. RESULTS: A total of 11 studies (15,966 mastectomy procedures) were included. We found an overall 5.99% SSI rate in our population. Three studies comparing topical antibiotics with no topical antibiotics demonstrated statistical significance (RR = 0.26, 95% CI: 0.12-0.60, P = 0.001), whereas 8 studies comparing extended systemic antibiotics with standard of care found no statistical significance (RR = 0.80, 95% CI: 0.60-1.08, P = 0.13). CONCLUSIONS: In the setting of IBR following mastectomy, there is insufficient evidence for the use of extended prophylactic antibiotics to reduce SSI rates. Well-designed randomized controlled trials in patients undergoing IBR should be conducted to determine the appropriate regimen and/or duration of prophylactic antibiotics on SSI outcomes.