Top Line: Can 5-fraction accelerated partial breast RT be delivered over 5 sequential days?
The Study: In the Florence trial, 5-fraction APBI using IMRT was delivered on non-consecutive days. With similar recurrence to whole breast RT at 10 years and excellent cosmesis, this technique has taken off as a treatment option for early stage breast cancer. ACCEL was a single-arm, phase 2 trial that assessed toxicity and cosmetic outcomes for APBI delivered over 5 consecutive days. It included 219 patients age 50 or older with hormone receptor positive, HER2 negative IDC or DCIS <3cm with negative margins and negative nodes. The APBI target was a 1cm CTV off the tumor bed plus a 7mm PTV margin. This received 27 Gy in 5 fraction using IMRT delivered on sequential days. The primary outcome was cosmesis compared to the whole breast arm of the RAPID trial. At 2 years, not a single patient had fair or poor cosmesis. In fact, 97% reported better cosmesis or no change from baseline. An obvious question is whether 30 Gy in 5 consecutive fractions would also result in similarly excellent cosmesis.
TBL: In the ACCEL trial, 27 Gy in 5 fractions IMRT-APBI given over 5 consecutive days results in virtually no adverse cosmesis at 2 years. | Grendarova, Int J Radiat Oncol Biol Phys 2023
The Study: In the Florence trial, 5-fraction APBI using IMRT was delivered on non-consecutive days. With similar recurrence to whole breast RT at 10 years and excellent cosmesis, this technique has taken off as a treatment option for early stage breast cancer. ACCEL was a single-arm, phase 2 trial that assessed toxicity and cosmetic outcomes for APBI delivered over 5 consecutive days. It included 219 patients age 50 or older with hormone receptor positive, HER2 negative IDC or DCIS <3cm with negative margins and negative nodes. The APBI target was a 1cm CTV off the tumor bed plus a 7mm PTV margin. This received 27 Gy in 5 fraction using IMRT delivered on sequential days. The primary outcome was cosmesis compared to the whole breast arm of the RAPID trial. At 2 years, not a single patient had fair or poor cosmesis. In fact, 97% reported better cosmesis or no change from baseline. An obvious question is whether 30 Gy in 5 consecutive fractions would also result in similarly excellent cosmesis.
TBL: In the ACCEL trial, 27 Gy in 5 fractions IMRT-APBI given over 5 consecutive days results in virtually no adverse cosmesis at 2 years. | Grendarova, Int J Radiat Oncol Biol Phys 2023