Evaluating the Relationships Between Rectal Normal Tissue Complication Probability and the Portion of Seminal Vesicles Included in the Clinical Target Volume in Intensity-Modulated Radiotherapy for Prostate Cancer

Doubling (1 to 2 cm) or comprehensively increasing (1 cm to full SVs) SV volume included in the CTV for patients with prostate IMRT is achievable in the majority of cases without exceeding RTOG dose-volume limits or underdosing the PTV and results in only a moderate increase in NTCP(R).