**Core Concept**
Ductal carcinoma in situ (DCIS) is a non-invasive form of breast cancer where malignant cells are confined to the milk ducts. It is a type of pre-invasive cancer, and the primary goal of management is to prevent progression to invasive cancer.

**Why the Correct Answer is Right**
The management of DCIS typically involves surgical excision, often followed by radiation therapy to eliminate any residual cancer cells. Lumpectomy (partial mastectomy) or mastectomy may be performed, depending on the extent and location of the DCIS. In some cases, radiation therapy alone may be sufficient for smaller lesions. The goal is to prevent local recurrence and minimize the risk of progression to invasive cancer.

**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect as it does not address the management of DCIS specifically.
**Option B:** This option is incorrect as radiation therapy alone is not typically sufficient for DCIS management.
**Option C:** This option is incorrect as it does not provide a specific treatment approach for DCIS.

**Clinical Pearl / High-Yield Fact**
It is essential to note that DCIS is a non-invasive cancer, and the management approach should focus on preventing progression to invasive cancer. A thorough discussion with the patient regarding the risks and benefits of different treatment options is crucial.

**Correct Answer:** D.