Abstract PD04-04: What is influencing breast conservation rates in the United States? Data from the National Accreditation Program of Breast Centers
Authors: Chagpar AB , Kaufman CS , Connolly J , Burgin C , Granville T , Winchester D 
Published: August 2014

INTRODUCTION: Breast conservation (BC) rates have been utilized as a quality metric, yet mastectomy rates have been noted to be increasing nationwide. The purpose of this study was to evaluate the factors associated with BC in 437 US breast centers surveyed by the National Accreditation Program of Breast Centers (NAPBC).

METHODS: From 2006 to 2010, 437 breast centers across the US were surveyed by the NAPBC. At each center, annual data regarding BC rates were reported in the Survey Application Record (SAR) for patients with Stage 0-II breast cancer. We evaluated characteristics of breast centers including geographic location, volume of patients treated, therapeutic modalities provided, and center organizational relationships. Non-parametric statistical analyses were performed to determine factors associated with BC rates in this cohort.

RESULTS: Among the 437 breast centers surveyed from 2006–2011, data on 77,248 patients with Stage 0-II were reported. The median number of Stage 0-II breast cancer patients per center was 149 (range; 10–891). The median proportion of these patients who underwent BC was 64.8% (range; 33–100%). No significant differences in median BC rate was noted over the six years of the study (range; 64.2% in 2006 – 67.1% in 2011, p = 0.788). However, significant regional variations were noted in median BC rates: 62.2% in the West (N = 59 centers), 63.8% in the South (N = 145 centers), 64.1% in the Midwest (N = 118 centers), and 70.8% in the Northeast (N = 104 centers), p &lt; 0.001. There was no difference noted in BC rates between high volume (≥ 150 Stage 0-II cases/yr) and low volume (&lt; 150 Stage 0-II cases/yr) centers (median 65.1% vs. 64.6%, respectively, p = 0.584). No differences in BC rate was noted between centers that referred vs. provided implant-based (p = 0.259), TRAM flap (p = 0.069), latissimus dorsi flap (p = 0.108) or DIEP/free flap (p = 0.324) reconstruction. Similarly, there was no difference noted in BC rates between centers who referred vs. provided whole breast radiation therapy (p = 0.224) and accelerated partial breast irradiation (p = 0.964). Centers that were affiliated with a hospital (N = 195) had a lower rate of BC than those that were not (n = 232); median 63.9% vs. 66.3%, p = 0.037. The majority of centers surveyed were also accredited by the Commission on Cancer (CoC; N=395); however, no differences were noted between these centers and those who were not CoC accredited in terms of BC rates (64.9% vs. 65.8%, respectively, p = 0.748). In a multivariate linear regression model, both region (p = 0.008) and hospital affiliation (p = 0.004) remained significant independent predictors of BC.

CONCLUSION: Across 437 US breast centers, data from 77,248 patients demonstrate a national BC rate of 64.8%. While the rate does not seem to be varying significantly over time, variation in BC was noted between regions and between centers associated with hospitals vs. not. Rates of BC do not vary, however, by center volume, availability of reconstruction or radiation, nor by CoC accreditation status. These data suggest that patient choice, rather than the availability of radiation and reconstruction, is the driving force in surgical decision-making.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr PD04-04.