TY - JOUR
T1 - A teaching intervention in a contouring dummy run improved target volume delineation in locally advanced non-small cell lung cancer
AU - Schimek-Jasch, Tanja
AU - Troost, Esther G. C.
AU - Ruecker, Gerta
AU - Prokic, Vesna
AU - Avlar, Melanie
AU - Duncker-Rohr, Viola
AU - Mix, Michael
AU - Doll, Christian
AU - Grosu, Anca-Ligia
AU - Nestle, Ursula
PY - 2015/6
Y1 - 2015/6
N2 - Introduction Interobserver variability in the definition of target volumes (TVs) is a well-known confounding factor in (multicentre) clinical studies employing radiotherapy. Therefore, detailed contouring guidelines are provided in the prospective randomised multicentre PET-Plan (NCT00697333) clinical trial protocol. This trial compares strictly FDG-PET-based TV delineation with conventional TV delineation in patients with locally advanced non-small cell lung cancer (NSCLC). Despite detailed contouring guidelines, their interpretation by different radiation oncologists can vary considerably, leading to undesirable discrepancies in TV delineation. Considering this, as part of the PET-Plan study quality assurance (QA), a contouring dummy run (DR) consisting of two phases was performed to analyse the interobserver variability before and after teaching. Materials and methods In the first phase of the DR (DR1), radiation oncologists from 14 study centres were asked to delineate TVs as defined by the study protocol (gross TV, GTV; and two clinical TVs, CTV-A and CTV-B) in a test patient. A teaching session was held at a study group meeting, including a discussion of the results focussing on discordances in comparison to the per-protocol solution. Subsequently, the second phase of the DR (DR2) was performed in order to evaluate the impact of teaching. Results Teaching after DR1 resulted in a reduction of absolute TVs in DR2, as well as in better concordance of TVs. The Overall Kappa(kappa) indices increased from 0.63 to 0.71 (GTV), 0.60 to 0.65 (CTV-A) and from 0.59 to 0.63 (CTV-B), demonstrating improvements in overall interobserver agreement. Conclusion Contouring DRs and study group meetings as part of QA in multicentre clinical trials help to identify misinterpretations of per-protocol TV delineation. Teaching the correct interpretation of protocol contouring guidelines leads to a reduction in interobserver variability and to more consistent contouring, which should consequently improve the validity of the overall study results.
AB - Introduction Interobserver variability in the definition of target volumes (TVs) is a well-known confounding factor in (multicentre) clinical studies employing radiotherapy. Therefore, detailed contouring guidelines are provided in the prospective randomised multicentre PET-Plan (NCT00697333) clinical trial protocol. This trial compares strictly FDG-PET-based TV delineation with conventional TV delineation in patients with locally advanced non-small cell lung cancer (NSCLC). Despite detailed contouring guidelines, their interpretation by different radiation oncologists can vary considerably, leading to undesirable discrepancies in TV delineation. Considering this, as part of the PET-Plan study quality assurance (QA), a contouring dummy run (DR) consisting of two phases was performed to analyse the interobserver variability before and after teaching. Materials and methods In the first phase of the DR (DR1), radiation oncologists from 14 study centres were asked to delineate TVs as defined by the study protocol (gross TV, GTV; and two clinical TVs, CTV-A and CTV-B) in a test patient. A teaching session was held at a study group meeting, including a discussion of the results focussing on discordances in comparison to the per-protocol solution. Subsequently, the second phase of the DR (DR2) was performed in order to evaluate the impact of teaching. Results Teaching after DR1 resulted in a reduction of absolute TVs in DR2, as well as in better concordance of TVs. The Overall Kappa(kappa) indices increased from 0.63 to 0.71 (GTV), 0.60 to 0.65 (CTV-A) and from 0.59 to 0.63 (CTV-B), demonstrating improvements in overall interobserver agreement. Conclusion Contouring DRs and study group meetings as part of QA in multicentre clinical trials help to identify misinterpretations of per-protocol TV delineation. Teaching the correct interpretation of protocol contouring guidelines leads to a reduction in interobserver variability and to more consistent contouring, which should consequently improve the validity of the overall study results.
KW - Target volume definition
KW - Radiochemotherapy
KW - Positron-emission tomography
KW - Dummy Run
KW - nodal irradiation
U2 - 10.1007/s00066-015-0812-8
DO - 10.1007/s00066-015-0812-8
M3 - Article
C2 - 25665799
SN - 0179-7158
VL - 191
SP - 525
EP - 533
JO - Strahlentherapie Und onkologie
JF - Strahlentherapie Und onkologie
IS - 6
ER -