Variation in Post-Surgical Lumpectomy Cavity Volume With Delay in Initiation of Breast Irradiation Because of Chemotherapy

Patients receiving CTX were at higher risk for local recurrence. However, as a result of lumpectomy bed contraction, these patients received a boost to a smaller volume than patients not receiving CTX. This finding is counterintuitive and supports re-evaluation of the optimal size of the boost field. In addition, these results may have implications for patients treated with partial breast irradiation.