Variation in applicator positions during interfraction high-dose rate brachytherapy in carcinoma cervix: dosimetric evaluation

Purpose: This study was designed to study the variations in different geometrical and dosimetric parameters. Materials and methods: In this study, two groups comprises 21 and 28 patients, who were treated with 9.5 Gy x 2 Fx and 7.5Gy x 3 Fx, respectively, using microselectron high-dose rate (HDR) remote control unit. All patients were analysed using orthogonal radiographs to evaluate variations in different parameters. Results: Variations in different parameters are more in Group II patients than in Group I patients, which show that the variation in geometrical and dosimetrical parameters increases with increasing HDR number of fractions. Conclusion: In the reporting of an outcome of multiple fractionation of HDR treatments resultant dosimetric parameters must be evaluated and must be used for clinical interpretation.