Predictive factors for the upstaging of Breast Ductal Carcinoma in Situ: assessing a patient retrospective cohort from a specialized breast cancer center.

Abstract

Introduction Ductal Carcinoma in Situ (DCIS) is a precursor lesion of Invasive Breast Carcinoma (IBC), but we cannot predict which will progress to invasive disease. This study aims to define the upstaging rate and to identify upstaging predictive factors in a DCIS sample. Materials and Methods This is a retrospective study that analyzed a consecutive sample of 207 patients with a pre-operative diagnosis of DCIS treated at Centro Hospitalar Universitário São João (CHUSJ). Using descriptive statistics, we evaluated variables such as preoperative size, clinical presentation, mammography presentation and extent of lesion. A receiver operating characteristic (ROC) curve was used to quantify the diagnostic ability of the tumour size by imaging and its most suitable cut-off. Results The upstaging rate obtained was 26,2% (48/183). Only tumour size by imaging was significantly associated with DCIS upstaging. A ROC curve using the tumour size by imaging showed a cutoff at 45.5 mm as the point maximizing sensitivity and specificity (area under the curve=0.634, 95% CI: 0.545-0.724; Gini Index=0.268). Conclusion One in every four patients with an DCIS lesion on initial diagnosis will get a final diagnosis of IBC, and this finding will impact the indication for sentinel lymph node biopsy (SLNB). Upstaging was associated with the tumour size by imaging. This study is a contribution to determine which DCIS patients should undergo SLNB due to an increased risk of a final diagnosis of an invasive/microinvasive carcinoma.