Survey of the use of the ICRU 38 in recording and reporting cervical cancer brachytherapy

Background: A survey on the practice of reporting intracavitary cervix cancer brachytherapy (LDR and HDR) in clinical practice (CP) and in literature (LIT) was performed on the occasion of a workshop, 'ICRU 38: The Basis for a Revision', which took place at the Annual GEC ESTRO meeting in Naples in 1998. Materials and methods: The answers (n = 85) to a specific questionnaire which had been sent to ail ESTRO members (n = 1600), were evaluated. Tn parallel, a systematic survey on the literature reporting cervix cancer brachytherapy since 1985 was performed using the MEDLINE database. The main recommendations for reporting as given in the ICRU 38 were addressed for both surveys: technique; total reference air kerma (TRAK); dose specification to the target volume '60 Gy reference volume', to organs at risk 'ICRU rectum and bladder point' and other reference points and time-dose pattern. In addition: some other items were investigated such as mg h, Point A, B, and in vivo dosimetry in bladder and rectum. Results: Issues related to technique (source, machine and applicator type) and to time-dose pattern are reported in the majority of patients in CP and LIT. The same applies for the following parameters: Point A is indicated in 76% (LDR) to 89% (HDR) in CP, in 60% (LDR) to 96% (HDR) in LIT. Rectum and bladder ICRU points are recorded in 55% (HDR) to 90% (LDR) and 58% (HDR) to 84% (LDR), respectively, in CP. On the other hand, TRAK is given in 14% (HDR) to 43% (LDR) in CP, in 0% (HDR) to 10% (LDR) in LIT. '60 Gy reference volume' is recorded in 18% (HDR) to 51% (LDR) in CP, in 0% (HDR) to 17% (LDR) in LIT. Rectum and bladder ICRU points are reported in 18% (LDR) to 28% (HDR) and 14% (HDR) to 29% (LDR), respectively, in LIT. Other reference points and in vivo dosimetry measurements are given in a low percentage. Dose rate and overall treatment time is reported in 100-44%. Conclusion: Recording and reporting in CP and in LIT meets the recommendations as given in ICRU 38 to different degrees. Specific items such as TRAK and the 'Reference volume' have only limited penetration into CP and LIT, which applies in particular to centers using HDR brachytherapy. The discrepancies between CP and LIT may be due to the well-known delay between change in CP and its translation into LIT. In order to arrive at a more common language for the better exchange of clinical results, it seems to be necessary to adapt some terms and recommendations. In particular, comprehensive concepts are needed for reporting dose to points and volumes in the target and in critical organs, according to the new potential from imaging and computer technology and from modern radiobiological insights, bridging the gap between LDR and HDR brachytherapy. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved