Abstract P2-14-03: Development and evaluation of a prediction model based on routine clinicopathological variables for predicting underestimated invasive breast cancer in women with ductal carcinoma in situ at stereotactic large core needle biopsy

• Published in: Cancer research (Chicago, Ill.) Vol. 73; no. 24_Supplement; pp. P2 - P2-14-03
• Main Authors: Diepstraten, SCE, van de Ven, SMWY, Pijnappel, RM, Peeters, PHM, van den Bosch, MAAJ, Verkooijen, HM, Elias, SG
• Format: Journal Article
• Language: English
• Published: 15.12.2013
• ISSN: 0008-5472; 1538-7445
• DOI: 10.1158/0008-5472.SABCS13-P2-14-03

Abstract Purpose: To develop a multivariable model for prediction of underestimated invasiveness in women with ductal carcinoma in situ (DCIS) at stereotactic large core needle biopsy (LCNB), that can be used to select patients for sentinel node biopsy (SNB) at primary surgery. Methods: From the literature, we selected potential preoperative predictors of underestimated invasive breast cancer. Data of patients with nonpalpable breast lesions who were diagnosed with DCIS at stereotactic LCNB, drawn from the COBRA (Core Biopsy after RAdiological localization) and COBRA2000 studies, were used to fit the multivariable model and assess its overall performance, discrimination, and calibration. Results: 348 women with LCNB-proven DCIS were available for analysis. In 100 (28.7%) patients invasive carcinoma was found at subsequent surgery. Nine predictors were included in the model. In the multivariable analysis, the predictors with the strongest association were lesion size (OR 1.12 per cm, 95% CI 0.98-1.28), the number of cores retrieved at biopsy (OR per core 0.87, 95% CI 0.75-1.01), presence of lobular cancerization (OR 5.29, 95% CI 1.25-26.77), and microinvasion (OR 3.75, 95% CI 1.42-9.87). The overall performance of the multivariable model was poor with an explained variation of 9% (Nagelkerke's R2), mediocre discrimination with area under the receiver operating characteristic curve of 0.66 (95% confidence interval 0.58-0.73), and fairly good calibration. Conclusion: The evaluation of our multivariable prediction model in a large, clinically representative study population, proves that routine clinical and pathological variables are not suitable to select patients with LCNB-proven DCIS for SNB during primary surgery. Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-14-03.