Phase 2 APBI multicatheter HDR brachytherapy (local radiation) single-fraction after lumpectomy

Virginia Commonwealth University (VCU) is running this Phase 2, single-arm prospective study to test the safety of accelerated partial breast irradiation delivered as multicatheter interstitial brachytherapy in a single fraction over 1 day—placing multiple catheters into/near the lumpectomy cavity to deliver a high, localized radiation dose (tumor-bed–focused radiotherapy). Eligible patients are women ages 40–85 with DCIS and/or invasive breast carcinoma after lumpectomy with negative margins (Tis–T2, with T2 ≤3 cm), with axillary staging required for invasive disease unless meeting specified older/low-risk, hormone-receptor–positive criteria. The commercial/scientific angle is “ultra-compressed” APBI: if toxicity and cosmesis remain acceptable, one-day brachytherapy could reduce treatment burden versus common contemporary care after lumpectomy—typically whole-breast external beam radiation over several weeks or a shorter hypofractionated course, or in selected low-risk patients, partial-breast external beam regimens over about 1–2 weeks plus appropriate endocrine therapy and HER2-directed therapy when indicated.