ESTRO PT 2018

Accelerated Partial-Breast Proton Therapy: Initial MGH Experience

Kozak, Taghian et al. IJROBP 66(3):691, 2006

• Phase I/II trial. 20 women with T-1 breast Ca, neg. margins after lumpectomy • PTV: lumpectomy cavity plus 1.5-2.0 cm, minimum 5mm distance to surface/skin

• 32 Gy(RBE) total dose: 4 Gy (RBE) B.I.D. over 4 days

• 1-3 field arrangements overall, 1 field treated per day only

• „Skin dose per field approached maximum dose“, Single field per day = full 4 Gy skin dose. (MGH, passive scatttering )

• Observation: Median F/U 12 months (8-22)

increased acute toxicity:

80% moderate to severe skin color changes

22% severe moist desquamation