High-grade/large lesions of DCIS require which treatment?

The treatment of high-grade or large lesions of Ductal Carcinoma In Situ (DCIS) often involves mastectomy along with irradiation. High-grade DCIS is associated with an increased risk of progression to invasive breast cancer and has a potential for multifocality, which makes conservative management less favorable.

Mastectomy is a surgical option that allows for the complete removal of the breast tissue, thereby minimizing the risk of recurrence compared to local excision alone. In conjunction with mastectomy, irradiation is typically recommended to further reduce the chances of any residual cancer cells leading to a recurrence.

Local excision may be effective for smaller, low-grade lesions, but in cases of high-grade or larger lesions, it may not adequately address the risk of invasive disease. Observation is not appropriate for high-grade DCIS because of the significant risk of progression, while radiation therapy alone is not sufficient as a standalone treatment option in this context. Thus, mastectomy combined with irradiation provides a more comprehensive approach to managing high-grade or large DCIS lesions.