Clinical Predictors of Upstaging to Invasive Cancer Postoperatively in Patients Diagnosed with Ductal Carcinoma In Situ before Surgery

Purpose: Upstaging to invasive cancer (IC) is often found after surgery in those patients diagnosed with ductal carcinoma in situ (DCIS) and who underwent preoperative needle biopsy. This may change the post-surgical plans that include the re-operation, chemotherapy, and/or radiotherapy. Yet, there are no clinically available factors to predict IC in preoperatively diagnosed DCIS patients. This study evaluated the clinical and pathological predictive risk factors for upgrading DCIS to IC. Methods: This study retrospectively evaluated those patients who were diagnosed with DCIS preoperatively, and this diagnosis was followed by performing breast surgery between Jan 2005 and June 2018. Clinico-pathological factors were collected for the analysis between the pure DCIS group and the IC group. Results: Of the 431 patients included in the study, 34 (7.9%) were upstaged to IC after surgery, and 397 (92.1%) were diagnosed as having pure DCIS. The nuclear grade was the sole predictor of upstaging to IC on the analysis of the clinico-pathological factors (odds ratio [OR] = 2.39, 95% confidence interval [95% CI] = 1.05 – 5.42, P = 0.038 on the univariate analysis; aOR = 2.86, 95% CI = 1.14 – 7.14, P = 0.025 on the multivariate analysis). The mass’s size and characteristics, as determined by sonography, were not predictive of IC. Conclusion: The sonographic findings were not significant factors for predicting IC in preoperative DCIS patients. A high nuclear grade was the only statistically significant factor associated with IC. Considering the variability of the gauge of biopsy needles or the method for needle biopsy, large-scale prospective studies that control these variables may well reveal available predictive factors of IC in patients with DCIS.