A low-dose ipsilateral lung restriction improves 3-d conformal planning for partial breast radiation therapy.
In trials of 3D conformal external beam partial breast radiotherapy (PBRT), the dosimetrist must balance the priorities of achieving high conformity to the target versus minimizing low-dose exposure to the normal structures. This study highlights the caveat that in the absence of a low-dose lung restriction, the use of relatively en-face fields may meet trial-defined requirements but expose the ipsilateral lung to unnecessary low-dose radiation. Adding a low-dose restriction that ≤ 20% of the ipsilateral lung should receive 10% of the prescribed dose resulted in successful plans in 88% of cases. This low-dose lung limit should be used in PBRT planning.
Mitchell
Tracy
T
Radiation Therapy Program, British Columbia Cancer Agency, Vancouver Island Centre, University of British Columbia, University of Victoria, Victoria, British Columbia, Canada.
Truong
Pauline T
PT
Salter
Lee
L
Graham
Cathy
C
Gaffney
Helene
H
Beckham
Wayne
W
Olivotto
Ivo A
IA
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001943:Breast Neoplasms / Q000532:radiotherapy*; D003198:Computer Simulation; D005260:Female; D006801:Humans; D008168:Lung / Q000528:radiation effects*; D008875:Middle Aged; D008954:Models, Biological; D009928:Organ Specificity; D011835:Radiation Protection / Q000379:methods*; D011874:Radiometry / Q000379:methods*; D011879:Radiotherapy Dosage; D011880:Radiotherapy Planning, Computer-Assisted / Q000379:methods*; D020266:Radiotherapy, Conformal / Q000379:methods*