Takahashi S, et al. - In the present study, researchers intended to compare the characteristics, clinical behavior, and biomarker profile between HER2 positive (HER2+) and triple-negative (TN) ductal carcinoma in situ (DCIS) which are considered more aggressive than other DCIS subtypes as well as examined the effect of these features on its potential of progression to invasive breast carcinomas. For this analysis, they identified cases of DCIS diagnosed at the Department of Pathology, Singapore General Hospital from 1994 to 2010. They found that HER2+ DCIS had more aggressive pathological characteristics compared to TN DCIS. Findings suggested that accumulation of mutant p53 could possibly be contributory. It was noted that age was an independent predictor of aggressive biological behavior of HER2+ and TN DCIS and younger patients with p53 positive HER2+ DCIS had a significantly adverse clinical outcome.