Study of factors influencing dose distribution of brachytherapy in cervical cancer

Objective: To study the factors which influence the dose distribution of brachytherapy in cervical cancer. Methods: Ninety-five patients with cervical cancer II - III b received fundamental radiation therapy including brachytherapy in our department from Aug. 2004 to Nov. 2005. The deviation of isodose curve of brachytherapy was based on A-B reference system, and the deviation of dose was defined by measuring in a practical standard body model. Results: The factors influencing isodose offset significantly were parametrial infiltrating degree, and anatomy factor of cervical cancer and operating skill. The degree of isodose offset could not be lowered with the increased frequency of brachytherapy. Conclusion: Making simulation in cervical brachytherapy is necessary not only for the identification of the deviation of isodose curve but also for adjusting the dose distribution and revising the plan of radiotherapy.