NSABP B-17 — Lumpectomy Compared With Lumpectomy and Radiation Therapy for the Treatment of Intraductal Breast Cancer (DCIS)

Phase 3 · 1993 · Ductal Carcinoma In Situ

Design

Randomized trial comparing lumpectomy alone versus lumpectomy plus breast radiotherapy in women with DCIS.

Population

Women with ductal carcinoma in situ (intraductal breast cancer) treated with breast-conserving surgery.

Primary Endpoint

Ipsilateral breast tumor recurrence (noninvasive and invasive)

Key Result

Adding radiotherapy reduced 5-year ipsilateral breast cancer from 16.4% to 7.0%, with invasive recurrence cut from 10.5% to 2.9% (P<0.001).

Guideline Impact

Radiation after breast-conserving surgery for DCIS in NCCN guidelines