Risk Factor of Invasive Breast Cancer in Patients with Preoperative Diagnosis of Ductal Carcinoma in Situ

ABSTRACT

PURPOSE: Ductal carcinoma in situ (DCIS), unlike invasive ductal carcinoma, does not require sentinel lymph node biopsy or axillary lymph node dissection because the possibility of axillary lymph node metastasis is low. However, occasionally, despite preoperative diagnosis of DCIS, invasive ductal carcinoma can be diagnosed by postoperative biopsy. Therefore, a study of the associated risk factors is necessary. METHODS: 198 patients with an initial diagnosis of DCIS, treated between February 2005 and December 2009, were retrospectively analyzed. Associations between clinical and pathologic factors were analyzed for significance using univariate and multivariate analyses. RESULTS: Of the 198 patients, 57 (28.8%) were found to have invasive disease on final pathology. Multivariate analysis revealed 4 independent predictors of invasive cancer upon final pathology: diagnosis by needle biopsy (OR, 3.165; P=0.008), positive p53 on preoperative biopsy (OR, 2.494; P=0.019) DCIS size (>2 cm) on microscopic finding (OR, 2.683; P=0.014), and relatively young age (OR, 0.958, P=0.046). Of the 13 patients with positive axillary lymph nodes, 11 (84.6%) were shown to have invasive cancer on final pathology (P<0.001). CONCLUSION: In cases of preoperative diagnosis based on needle biopsy, positive p53, large tumor, and relatively young age, an SLNB procedure can be considered because in almost 30% of the patients an invasive carcinoma is found after surgery.