No abstract

Radiotherapy (RT) is commonly used as adjuvant treatment following hysterectomy and double oophorectomy in endometrial carcinoma. Prophylactic vaginal brachytherapy (BT) is the most common treatment in BT units. The PORTEC and GOG 99 studies have attempted to clarify the indications of BT and postoperative external RT, changing treatment standards. However, prophylactic BT regimens are very varied and there is currently no consensus on how to treat patients in terms of dose per fraction and number of fractions. Moreover, unoperated cases of endometrium are uncommon and there is limited experience in their treatment with BT. The 9th Consensus Meeting of the SEOR and SEFM Brachytherapy Group, held in Malaga on 11 March 2011, was therefore dedicated to "Brachytherapy in Endometrial Carcinoma". This article presents the consensus on treatment of endometrial carcinoma in operated (prophylactic vaginal BT) and unoperated (endouterine BT) patients.

With this method, we are able to reduce the positioning accuracy to 0.2 mm. Consequently, the dose distribution in the junction of abutted fields is highly smoothed, achieving the maximum dose heterogeneity to be less than 3%.

The new multislice computed tomography (CT) machines require some new methods of shielding calculation, which need to be analysed. NCRP Report No. 147 proposes three shielding calculation methods based on the following dosimetric parameters: weighted CT dose index for the peripheral axis (CTDI(w, per)), dose-length product (DLP) and isodose maps. A survey of these three methods has been carried out. For this analysis, we have used measured values of the dosimetric quantities involved and also those provided by the manufacturer, making a comparison between the results obtained. The barrier thicknesses when setting up two different multislice CT instruments, a Philips Brilliance 16 or a Philips Brilliance 64, in the same room, are also compared. Shielding calculation from isodose maps provides more reliable results than the other two methods, since it is the only method that takes the actual scattered radiation distribution into account. It is concluded therefore that the most suitable method for calculating the barrier thicknesses of the CT facility is the one based on isodose maps. This study also shows that for different multislice CT machines the barrier thicknesses do not necessarily become bigger as the number of slices increases, because of the great dependence on technique used in CT protocols for different anatomical regions.

No abstract