- Patients enrolled in the NSABP B-17 trial:
- Were randomly assigned to receive partial mastectomy only or partial mastectomy followed by lattice radiotherapy (LRT; a novel technique of delivering heterogeneous doses of radiation to voluminous tumors not amenable to surgery):
- For the treatment of localized DCIS
- The trial showed:
- A clear benefit for the addition of radiation
- Were randomly assigned to receive partial mastectomy only or partial mastectomy followed by lattice radiotherapy (LRT; a novel technique of delivering heterogeneous doses of radiation to voluminous tumors not amenable to surgery):
- Patients enrolled in the NSABP B-24 trial:
- Were randomly assigned to receive LRT or LRT plus tamoxifen (LRTT)
- At 15-year follow-up, the risk of death in these trials was low:
- Ranging from 2.3% for patients who had LRTT to 4.7% for patients who had LRT
- Ipsilateral breast tumor recurrence was:
- 35% (19.6% invasive, 15.4% DCIS) in the lumpectomy only arm of B-17 and 19.8% (10.7% invasive, 9.0% DCIS) in the LRT arm
- In B-24 IBRT was 16.6% (9.0 invasive, 7.6% DCIS) in the LRT arm and 13.2% (6.6% invasive, 6.7% DCIS) in the LRTT arm
- The risk of contralateral new primary ranged from:
- 4.9% (3.3% invasive, 1.6% DCIS) in the LRTT arm of B-24 to 9.3% (5.6% invasive, 3.7% DCIS) in the LRT arm of B-17
References
1. Wapnir IL, Dignam JJ, Fisher B, Mamounas EP, Anderson SJ, Julian TB, et al. Long-term outcomes of invasive ipsilateral breast tumor recurrences after lumpectomy in NSABP B-17 and B-24 randomized clinical trials for DCIS. J Natl Cancer Inst. 2011;103(6):478-488.
Rodrigo Arrangoiz MS, MD, FACS, FSSO 