Risk perception of patients with ductal carcinoma in situ (DCIS) of the breast and their healthcare practitioners: The importance of histopathological terminology, and the gaps in our knowledge.

Despite ductal carcinoma in situ (DCIS) being a non-obligatory precursor of invasive breast carcinoma, its diagnosis generates substantial psychological distress. The limited knowledge about the natural history of DCIS contributes to the insufficient transmission of information about DCIS to patients and the general population. The uncertainty about the progression risk to invasive carcinoma hampers adequate communication by clinicians. Breast cancer-related mortality after a DCIS diagnosis is low. However, several studies have demonstrated that DCIS patients generally overestimate the risk of developing loco-regional recurrence or dying from breast cancer. Various factors contribute to this perceived risk. Despite the lack of infiltrative growth, DCIS is treated similarly to invasive breast cancer, with surgery, radiotherapy, and hormonal therapy. Additionally, the term 'carcinoma' in DCIS provokes anxiety. Incorrect risk perception by physicians may result in overtreatment. Here, we provide an overview of epidemiologic data on mortality after DCIS. We discuss the impact of the term 'ductal carcinoma in situ' on patients' and physicians' perceptions of risk. The available evidence is mostly limited to patients within the Anglosphere. Recent studies, and European studies in particular, are scarce. We identify this as an area of interest for future large-scale European studies. We discuss the potential value of the "ductal intraepithelial neoplasia" (DIN) terminology, introduced in 1998. Although replacing the concept of 'DCIS' with the DIN terminology is unlikely to solve the entire problem of risk overestimation, it could be the first step to optimize doctor-patient communication and alter the current risk perception.