ABSTRACT
Objective To investigate the dosimetry and feasibility of target volume reduction in three-dimensional conformal radiotherapy for non-small cell lung cancer(NSCLC).Methods Two differ-ent radiation treatment planning,the conventional conformal planning and the small volume conformal plan-ning,were designed for 32 NSCLC patients.Dose-olume histograms were used to assess the dosimetric dis-parity in target regions and surrounding organs at risk.Results Small volume conformal planning could meet the demand of target dose.The least dose,the maximum dose,and the mean dose at subclinical targets were 50.93 Gy,54.60 Gy and(52.37 ±1.02)Gy,respectively.Comparing with the conventional conformal planning,small volume conformal planning reduced the mean dose of lung,spinal cord and esophagus(P<0.05).Conclusion Small volume conformal planning can meet the dosimetric requirement of target vol-ume for NSCLC and reduce the dose of normal tissues,which is worthy of further clinical study.