Indian Brachytherapy Society Guidelines for radiotherapeutic management of cervical cancer with special emphasis on high-dose-rate brachytherapy.

Brachytherapy (BT) for locally advanced cervical cancer is vital for optimal outcomes. There is heterogeneity in brachytherapy treatment practice for cervical cancer across India. In an attempt to standardize various processes involved in cervical cancer brachytherapy, the expert members of the Indian Brachytherapy Society (IBS) developed a document related to radiation therapy treatment of cervical cancer with special emphasis on brachytherapy. The guidelines are based on high quality clinical evidence, expert opinion and consensus wherever evidence was lacking. The document provides a guide for external beam radiation and details of all the processes involved in high-dose-rate (HDR) brachytherapy including patient selection, preparation, principles and technique of BT applications, target and normal tissue definition, dose prescriptions, BT planning, reporting parameters, common complications of BT and their management, scope for research, etc. In summary, we present here practical tips and tricks, recording and reporting of cervical cancer brachytherapy, which can be implemented in various clinical environments and forms the basis of this report.

Vienna-II ring applicator for distal parametrial/pelvic wall disease in cervical cancer brachytherapy: An experience from two institutions: Clinical feasibility and outcome.

PURPOSE: Recent evidence from EMBRACE shows that around 16% patients with locally advanced cervical cancer (LACC) have residual tumor in distal parametrium (DP) and pelvic wall disease (LPW) after concurrent radio-chemotherapy (CCRT). Adequate target coverage with standard brachytherapy approaches represents a challenge. Therefore, we modified the Vienna I applicator with an add-on cap allowing for additional oblique needles into the DP/LPW (Vienna II). We report here the feasibility and clinical outcomes using Vienna II applicator in LACC patients treated in 2 institutions. METHODS AND MATERIALS: 69 patients with residual disease in DP/LPW after CCRT were accrued. FIGO (2009) stage was 26% IIB, 52% III, 15% IVA, 7% IVB (para-aortic nodes). At diagnosis 91% had disease involving DP/LPW. After CCRT, patients underwent image guided adaptive brachytherapy (IGABT) using Vienna II applicator. IGABT details, acute complications, dose volume parameters and clinical outcome variables were compiled and analyzed. RESULTS: Residual DP/LPW disease at BT was found in 90% patients. Median total number of needles were 7 [3-15], oblique 4 [1-7]. Manageable intraoperative utero-vaginal complications occurred in 8 patients and manageable arterial bleeding in 6 patients during removal. Mean distance between tandem and outer contour of CTVHR was 38 mm and mean CTVHR (±SD) volume was 69 ±â€¯32 cm3. The mean D90 CTVHR was 86 ±â€¯7 Gy (EQD2) and mean (±SD) D2cm3 (Gy, EQD2) 86 ±â€¯12, 68 ±â€¯7, 68 ±â€¯9 for bladder, rectum and sigmoid respectively. Actuarial LC, PFS, OS at 3/5 years was 76/72%, 56/50%, 62/54% and G3-4 late toxicities (n = 23) were observed in 14 patients (20%). CONCLUSIONS: IGABT using Vienna II applicator allows for appropriate target coverage in tumors extending into DP/LPW at the time of BT. Clinical use is feasible and results in good local control, DFS and OS with moderate rate of acute and late ≥G3 toxicity.

Setup error analysis in helical tomotherapy based image-guided radiation therapy treatments.

The adequacy of setup margins for various sites in patients treated with helical tomotherapy was investigated. A total of 102 patients were investigated. The breakdown of the patients were as follows: Twenty-five patients each in brain, head and neck (H and N), and pelvis, while 12 patients in lung and 15 in craniospinal irradiation (CSI). Patients were immobilized on the institutional protocol. Altogether 2686 megavoltage computed tomography images were analyzed with 672, 747, 622, 333, and 312 fractions, respectively, from brain, H and N, pelvis, lung, and CSI. Overall systematic and random errors were calculated in three translational and three rotational directions. Setup margins were evaluated using van Herk formula. The calculated margins were compared with the margins in the clinical use for various directions and sites. We found that the clinical isotropic margin of 3 mm was adequate for brain patients. However, in the longitudinal direction it was found to be out of margin by 0.7 mm. In H and N, the calculated margins were well within the isotropic margin of 5 mm which is in clinical use. In pelvis, the calculated margin was within the limits, 8.3 mm versus 10 mm only in longitudinal direction, however, in vertical and lateral directions the calculated margins were out of clinical margins 11 mm versus 10 mm, and 8.7 mm versus 7.0, mm respectively. In lung, all the calculated margins were well within the margins used clinically. In CSI, the variation was found in the middle spine in the longitudinal direction. The clinical margins used in our hospital are adequate enough for sites H and N, lung, and brain, however, for CSI and pelvis the margins were found to be out of clinical margins.

Dose optimization in gynecological 3D image based interstitial brachytherapy using martinez universal perineal interstitial template (MUPIT) -an institutional experience.

The aim of this study was to evaluate the dose optimization in 3D image based gynecological interstitial brachytherapy using Martinez Universal Perineal Interstitial Template (MUPIT). Axial CT image data set of 20 patients of gynecological cancer who underwent external radiotherapy and high dose rate (HDR) interstitial brachytherapy using MUPIT was employed to delineate clinical target volume (CTV) and organs at risk (OARs). Geometrical and graphical optimization were done for optimum CTV coverage and sparing of OARs. Coverage Index (CI), dose homogeneity index (DHI), overdose index (OI), dose non-uniformity ratio (DNR), external volume index (EI), conformity index (COIN) and dose volume parameters recommended by GEC-ESTRO were evaluated. The mean CTV, bladder and rectum volume were 137 ± 47cc, 106 ± 41cc and 50 ± 25cc, respectively. Mean CI, DHI and DNR were 0.86 ± 0.03, 0.69 ± 0.11 and 0.31 ± 0.09, while the mean OI, EI, and COIN were 0.08 ± 0.03, 0.07 ± 0.05 and 0.79 ± 0.05, respectively. The estimated mean CTV D90 was 76 ± 11Gy and D100 was 63 ± 9Gy. The different dosimetric parameters of bladder D2cc, D1cc and D0.1cc were 76 ± 11Gy, 81 ± 14Gy, and 98 ± 21Gy and of rectum/recto-sigmoid were 80 ± 17Gy, 85 ± 13Gy, and 124 ± 37Gy, respectively. Dose optimization yields superior coverage with optimal values of indices. Emerging data on 3D image based brachytherapy with reporting and clinical correlation of DVH parameters outcome is enterprizing and provides definite assistance in improving the quality of brachytherapy implants. DVH parameter for urethra in gynecological implants needs to be defined further.