DCIS: Risk Assessment in the Molecular Era

Area of Science:

• Oncology
• Genomics
• Breast Cancer Research

Background:

• Ductal carcinoma in situ (DCIS) accounts for 20% of breast cancers.
• Standard treatment involves breast-conserving surgery (BCS) and radiotherapy (RT), with endocrine therapy for hormone-receptor positive disease.
• RT significantly reduces in-breast recurrence but prompts interest in de-escalation for low-risk cases.

Purpose of the Study:

• To review current molecular risk assessment tools for DCIS.
• To evaluate their role in guiding postoperative RT decisions after BCS.
• To discuss ongoing trials on omitting surgery for low-risk DCIS.

Main Methods:

• Review of published literature on DCIS molecular assays.
• Analysis of clinical-pathologic features used in risk stratification.
• Discussion of genomic assays like Oncotype DX Breast DCIS Score and DCISionRT.
• Examination of clinical trials investigating treatment de-escalation.

Main Results:

• Genomic assays offer individualized prediction of RT benefit.
• These tools, combined with clinical-pathologic factors, enhance risk assessment.
• High local control rates with current BCT support de-escalation efforts.

Conclusions:

• Molecular assays show promise in personalizing RT recommendations for DCIS.
• Selective de-escalation of RT is a key focus in DCIS management.
• Further research and trials are exploring treatment omission for select low-risk DCIS patients.