A prospective cohort study identifying radiologic and tumor related factors of importance for breast conserving surgery after neoadjuvant chemotherapy.

INTRODUCTION: Neoadjuvant chemotherapy (NAC) is an established treatment option for early breast cancer, potentially downstaging the tumor and increasing the eligibility for breast-conserving surgery (BCS). The primary aim of this study was to assess the rate of BCS after NAC, and the secondary aim was to identify predictors of application of BCS after NAC. MATERIALS AND METHODS: This was an observational prospective cohort study of 226 patients in the SCAN-B (Clinical Trials NCT02306096) neoadjuvant cohort during 2014-2019. Eligibility for BCS was assessed at baseline and after NAC. Uni- and multivariable logistic regression analyses were performed using covariates with clinical relevance and/or those associated with outcome (BCS versus mastectomy), including tumor subtype, by gene expression analysis. RESULTS: The overall BCS rate was 52%, and this rate increased during the study period (from 37% to 52%). Pathological complete response was achieved in 69 patients (30%). Predictors for BCS were smaller tumor size on mammography, visibility on ultrasound, histological subtype other than lobular, benign axillary status, and a diagnosis of triple-negative or HER2-positive subtype, with a similar trend for gene expression subtypes. Mammographic density was negatively related to BCS in a dose-response pattern. In the multivariable logistic regression model, tumor stage at diagnosis and mammographic density showed the strongest association with BCS. CONCLUSION: The rate of BCS after NAC increased during the study period to 52%. With modern treatment options for NAC the potential for tumor response and BCS eligibility might further increase.

Validated prediction model for positive resection margins in breast-conserving surgery based exclusively on preoperative data.

BACKGROUND: Positive margins after breast-conserving surgery (BCS) and subsequent second surgery are associated with increased costs and patient discomfort. The aim of this study was to develop a prediction model for positive margins based on risk factors available before surgery. METHODS: Patients undergoing BCS for in situ or invasive cancer between 2015 and 2016 at site A formed a development cohort; those operated during 2017 in site A and B formed two validation cohorts. MRI was not used routinely. Preoperative radiographic and tumour characteristics and method of operation were collected from patient charts. Multivariable logistic regression was used to develop a prediction model for positive margins including variables with discriminatory capacity identified in a univariable model. The discrimination and calibration of the prediction model was assessed in the validation cohorts, and a nomogram developed. RESULTS: There were 432 patients in the development cohort, and 190 and 157 in site A and B validation cohorts respectively. Positive margins were identified in 77 patients (17.8 per cent) in the development cohort. A non-linear transformation of mammographic tumour size and six variables (visible on mammography, ductal carcinoma in situ, lobular invasive cancer, distance from nipple-areola complex, calcification, and type of surgery) were included in the final prediction model, which had an area under the curve of 0.80 (95 per cent c.i. 0.75 to 0.85). The discrimination and calibration of the prediction model was assessed in the validation cohorts, and a nomogram developed. CONCLUSION: The prediction model showed good ability to predict positive margins after BCS and might, after further validation, be used before surgery in centres without the routine use of preoperative MRI.Presented in part to the San Antonio Breast Cancer Symposium, San Antonio, Texas, USA, December 2018 and the Swedish Surgical Society Annual Meeting, Helsingborg, Sweden, August 2018.

Cosmetic Outcomes and Symmetry Comparison in Patients Undergoing Bilateral Therapeutic Mammoplasty for Breast Cancer.

BACKGROUND: Breast-reduction techniques are increasingly used in oncoplastic breast surgery. Bilateral therapeutic mammoplasty has the benefit of decreasing breast volume, enabling resection of larger tumors, and the potential to assure good postoperative symmetry. The aims of this study were to objectively asses the cosmetic outcomes of therapeutic mammoplasty in patients with breast cancer, using the breast cancer conservative treatment cosmetic results (BCCT.core) software, to compare this score with the surgeon's score and the patient's assessment, and to evaluate if other defined parameters have an impact on cosmetic outcomes. The secondary aim was to compare breast symmetry pre- and postoperatively. MATERIALS AND METHODS: We enrolled 146 consecutive patients with primary breast cancer who underwent therapeutic mammoplasty between 2011 and 2018 in Kristianstad Central Hospital, Sweden. We retrospectively collected data from patients' records. We analyzed the BCCT.core score using postoperative photographs to objectively evaluate cosmetic outcomes on a four-grade scale and compared with preoperative photographs to evaluate symmetry. Cosmetic outcomes were also assessed subjectively by patients and surgeons, using a 10-point Likert scale. RESULTS: The majority of patients (89%) had good or excellent BCCT.core scores, which correlated with surgeons' scores, rs = - 0.22 (p < 0.001). Overall, patients were more satisfied with the cosmetic outcomes than the surgeons (p < 0.001). Evidence supporting an association between the defined clinicopathological variables, for example, tumor size, and cosmetic outcomes, was weak. CONCLUSION: Therapeutic mammoplasty yields a very good cosmetic outcome, evaluated both by subjective and objective measurements. Importantly, symmetry can be improved in patients with asymmetry.