Decrease of the lumpectomy cavity volume after whole-breast irradiation affects small field boost planning.

To determine whether small field boost (SFB) replanning is necessary when the lumpectomy cavity (LPC) decreases during whole-breast irradiation (WBI) and what parameters might predict a change in the SFB plan. Forty patients had computed tomography (CT) simulation (CT1) within 60 days of surgery and were resimulated (CT2) after 37.8-41.

Repeat computed tomography simulation to assess lumpectomy cavity volume during whole-breast irradiation.

Purpose: To determine whether the lumpectomy cavity (LPC) decreases in volume during whole-breast radiotherapy (RT) and what factors influence the decrease.

Patients And Methods: Forty-three women with 44 breast lesions were prospectively enrolled. Eligible patients underwent lumpectomy followed by a CT simulation (CT1) within 60 days of surgery.