PURPOSE The purpose of this work was the biological comparison between Low Dose Rate (LDR) and Pulsed Dose Rate (PDR) in cervical cancer regarding the discontinuation of the afterloading system used for the LDR treatments at our Institution since December 2009. MATERIAL AND METHODS In the first phase we studied the influence of the pulse dose and the pulse time in the biological equivalence b...

Abstract Introduction: The accuracy an assessment of out- of- field dose due to secondary cancer risk is clinically important. Actually radiotherapy treatment planning systems are not commissioned for the out-of-field dose calculations, so the estimation of dose distributions by TPSs beyond the borders of treatment fields is not well calculate...

BACKGROUND For cervical carcinoma cases, this study aimed to evaluate the quality of intensity-modulated radiation therapy (IMRT) plans optimized by biological constraints. Furthermore, a new integrated strategy in biological planning module was proposed and verified. METHODS Twenty patients of advanced stage cervical carcinoma were enrolled in this study. For each patient, dose volume optimi...

BACKGROUND To compare intracavitary brachytherapy (ICBT) planning methods for cervical cancer, based on either orthogonal radiographs (conventional plan) or CT sections (CT plan); the comparison focused on target volume coverage and dose volume analysis of organs at risk (OARs), by representing point doses defined by the International Commission on Radiation Units and Measurement (ICRU) and dos...

PURPOSE We perform a clinical retrospective study to determine whether a vaginal balloon-packing system provides a dosimetric reduction to organs at risk (OARs) versus traditional gauze packing for gynecological high-dose-rate brachytherapy (HDR-BT). We also test various balloon filling materials for optimizing imaging quality. MATERIAL AND METHODS Filling materials for balloon-packing were e...

Objective: In locally advanced cervical cancer, the management consists of external beam radiotherapy and brachytherapy. The impact of intracavitary brachytherapy versus interstitial brachytherapy on local tumor control, survival and complications were prospectively investigated in this study. Methods: A total of 60 patients with stage IIB, IIIB cervical cancer were treated using a combination ...

Brachytherapy plays an important role in the definitive treatment of cervical cancers by radiotherapy. In the present study, we investigated whether sliding-window intensity-modulated radiation therapy (IMRT) can achieve a pear-shaped distribution with a similar sharp dose falloff identical to that of brachytherapy. The computed tomography scans of a tandem and ovoid patient were pushed to both...

PURPOSE To investigate the feasibility of progressive knowledge modeling for IMRT/VMAT treatment planning for multiple cancer types in the pelvic region. METHODS The treatment planning knowledge model quantifies correlations between patient anatomical features and the OAR dose sparing features. The model is trained with prior plans using a stepwise regression machine learning technique. The p...

The purpose of this study is to use the same diagnostic-quality verification and planning CTs to validate planning margin account for residual interfractional variations with image-guided soft tissue alignment of the prostate. For nine pros-tate cancer patients treated with IMRT to 78 Gy in 39 fractions, daily verification CT-on-rails images of the first seven and last seven fractions (n = 126)...

PURPOSE To investigate the dosimetric difference due to the different point A definitions in cervical cancer low-dose-rate (LDR) intracavitary brachytherapy. MATERIAL AND METHODS Twenty CT-based LDR brachytherapy plans of 11 cervical patients were retrospectively reviewed. Two plans with point As following the modified Manchester system which defines point A being 2 cm superior to the cervica...