Ductal Carcinoma In Situ (DCIS) represents a non-invasive form of breast cancer where abnormal cells are contained within the milk ducts of the breast. These cells have not spread into the surrounding breast tissue, meaning they are “in situ” or “in place.” When a diagnosis includes “grade 3,” it refers to a specific classification of these abnormal cells based on their appearance under a microscope. This grading system helps characterize the cellular behavior of the DCIS.
Understanding High-Grade DCIS
Grade 3 Ductal Carcinoma In Situ indicates that abnormal cells differ significantly from normal breast cells. These high-grade cells grow faster than lower-grade DCIS, exhibiting larger, irregularly shaped nuclei and increased cell division under a microscope. High-grade DCIS has a greater potential to progress to invasive breast cancer if untreated. Necrosis, or dead cancer cells accumulating within the milk duct, is a common feature. This, particularly central or “comedo” necrosis, often correlates with calcifications visible on mammograms.
Identifying High-Grade DCIS
High-grade Ductal Carcinoma In Situ is often detected during routine breast screening. Mammography is the primary imaging tool, frequently revealing calcifications, which are small calcium deposits. Fine linear or branching calcifications are often associated with high-grade DCIS and necrosis. If a mammogram identifies an area of concern, further diagnostic procedures are performed, including diagnostic mammograms for magnified views, and sometimes ultrasound or MRI for additional assessment. A biopsy, such as a core needle biopsy guided by imaging, is then performed to obtain tissue samples and confirm the diagnosis.
Treatment Options
Treatment for high-grade Ductal Carcinoma In Situ involves surgical removal of the abnormal cells. Breast-conserving surgery, or lumpectomy, removes the DCIS with a margin of healthy tissue. The aim is to achieve clear margins, meaning no cancer cells are at the edges of the removed tissue. If margins are not clear, additional surgery may be necessary. For widespread or multifocal disease, a mastectomy, which removes the entire breast, may be recommended.
Following a lumpectomy, radiation therapy is often advised. This targets any remaining abnormal cells and reduces the likelihood of recurrence or progression to invasive cancer. Radiation therapy is not typically needed after a mastectomy for DCIS.
For hormone receptor-positive high-grade DCIS, hormone therapy may be prescribed. Medications like tamoxifen or aromatase inhibitors are used, often for 5 to 10 years. This therapy lowers the risk of recurrence in the treated breast or new cancer development in either breast. Chemotherapy is generally not used for DCIS, as it is a non-invasive condition.
Life After Treatment and Outlook
The prognosis for high-grade Ductal Carcinoma In Situ is favorable with effective treatment. Treatment aims to eliminate abnormal cells and minimize the risk of recurrence or progression to invasive breast cancer, with a high success rate. Ongoing follow-up care is important, involving regular mammograms to monitor the treated breast for recurrence and screen the other breast. Clinical breast exams are also routinely performed. While DCIS is confined to the ducts, invasive cancer might be identified during surgical pathology, leading to treatment plan adjustments.