9 Reporting in Brachytherapy: Dose and Volume Specification

208 Reporting in Brachytherapy

The methods used to determine the volumes and the doses should always be reported. If in vivo measurements were performed, the technique and results should also be reported.

8.6 Quantities, reference points and volumes recommended for reporting intracavitary therapy for cervix carcinoma: Summary Following data are recommended for reporting intracavitary therapy for cervix carcinoma. 8.6.1 Description as complete as possible of the clinical conditions (see section 2, p. 158) (a) 8.6.2 Complete description of the technique (see section 3, p. 163) (a) 8.6.3 Complete description of the time-dose pattern (see section 5, p. 168) (a) 8.6.4 Treatment prescription (see section 1.1, p. 155) (a) 8.6.5 Total Reference Air Kerma (TRAK) (see section 4, p. 165) (b) 8.6.6. Dose at reference points : Point A and reference points related to bony structures (see sections 8.3.1-4) (c) 6.7 Volumes for reporting and their dimensions : Treated Volume, „point A volume”, reference volume (see sections 8.4.1-3) (d) 6.8 Dose to Organs at Risk : bladder, rectum (see section 8.5, p. 206) (e)(f) NB : Reporting at level 2 (3) shall always include all data that are recommended at level 1 (a) The clinical conditions, treatment technique, time-dose pattern, treatment prescription should be described as completely as possible when reporting at level 1, completely at level 2. (b) The TRAK should be, and can be reported at level 1. (c) The dose at Point(s) A should be reported at level 1 (see definition in section 8.3.1). When a fixed, fully rigid applicator is used, determination of absorbed dose to point A is straightforward and can usually be derived from pre-calculated sets of tables/isodose charts, as point A is defined in relation to the sources/applicator. The same is true also when semi-rigid or semi-fixed applicators are used for which only a limited number of source geometries are possible. For applicators where the positions of the sources, relative to each other are not fixed, calculation of dose to point A is possible based on reconstruction from orthogonal or quasi orthogonal radiographs. Doses at other anatomical reference points can also be evaluated and reported at level 1 based on the evaluation of the orthogonal radiographs: pelvic wall reference point(s) and lymphatic trapezoid (see section 8.3.3 and 8.3.4). However, the procedures take time and may be difficult to establish when only level 1 reporting is possible. Doses for all anatomical reference points mentioned above should be reported at level 2. (d) Reporting the dimensions of the Treated Volume, the Point A Volume and the Reference Volumes (e.g. 60, 75, 85 Gy volumes) is typically part of reporting at level 2. However, at level 1 it is possible to report the 3 dimensions based on standard dose distributions, e.g. from an atlas or a computer “library”.