TY - JOUR
T1 - Geometric contour variation in clinical target volume of axillary lymph nodes in breast cancer radiotherapy
T2 - an AIRO multi-institutional study
AU - Leonardi, Maria Cristina
AU - Pepa, Matteo
AU - Gugliandolo, Simone Giovanni
AU - Luraschi, Rosa
AU - Vigorito, Sabrina
AU - Rojas, Damaris Patricia
AU - La Porta, Maria Rosa
AU - Cante, Domenico
AU - Petrucci, Edoardo
AU - Marino, Lorenza
AU - Borzì, Giuseppina
AU - Ippolito, Edy
AU - Marrocco, Maristella
AU - Huscher, Alessandra
AU - Chieregato, Matteo
AU - Argenone, Angela
AU - Iadanza, Luciano
AU - De Rose, Fiorenza
AU - Lobefalo, Francesca
AU - Cucciarelli, Francesca
AU - Valenti, Marco
AU - De Santis, Maria Carmen
AU - Cavallo, Anna
AU - Rossi, Francesca
AU - Russo, Serenella
AU - Prisco, Agnese
AU - Guernieri, Marika
AU - Guarnaccia, Roberta
AU - Malatesta, Tiziana
AU - Meaglia, Ilaria
AU - Liotta, Marco
AU - Tabarelli de Fatis, Paola
AU - Palumbo, Isabella
AU - Marcantonini, Marta
AU - Colangione, Sarah Pia
AU - Mezzenga, Emilio
AU - Falivene, Sara
AU - Mormile, Maria
AU - Ravo, Vincenzo
AU - Arrichiello, Cecilia
AU - Fozza, Alessandra
AU - Barbero, Maria Paola
AU - Ivaldi, Giovanni Battista
AU - Catalano, Gianpiero
AU - Vidali, Cristiana
AU - Aristei, Cynthia
AU - Giannitto, Caterina
AU - Miglietta, Eleonora
AU - Ciabattoni, Antonella
AU - Meattini, Icro
AU - Orecchia, Roberto
AU - Cattani, Federica
AU - Jereczek-Fossa, Barbara Alicja
PY - 2021/7/1
Y1 - 2021/7/1
N2 - OBJECTIVES: To determine interobserver variability in axillary nodal contouring in breast cancer (BC) radiotherapy (RT) by comparing the clinical target volume of participating single centres (SC-CTV) with a gold-standard CTV (GS-CTV). METHODS: The GS-CTV of three patients (P1, P2, P3) with increasing complexity was created in DICOM format from the median contour of axillary CTVs drawn by BC experts, validated using the simultaneous truth and performance-level estimation and peer-reviewed. GS-CTVs were compared with the correspondent SC-CTVs drawn by radiation oncologists, using validated metrics and a total score (TS) integrating all of them. RESULTS: Eighteen RT centres participated in the study. Comparative analyses revealed that, on average, the SC-CTVs were smaller than GS-CTV for P1 and P2 (by -29.25% and -27.83%, respectively) and larger for P3 (by +12.53%). The mean Jaccard index was greater for P1 and P2 compared to P3, but the overlap extent value was around 0.50 or less. Regarding nodal levels, L4 showed the highest concordance with the GS. In the intra-patient comparison, L2 and L3 achieved lower TS than L4. Nodal levels showed discrepancy with GS, which was not statistically significant for P1, and negligible for P2, while P3 had the worst agreement. DICE similarity coefficient did not exceed the minimum threshold for agreement of 0.70 in all the measurements. CONCLUSIONS: Substantial differences were observed between SC- and GS-CTV, especially for P3 with altered arm setup. L2 and L3 were the most critical levels. The study highlighted these key points to address. ADVANCES IN KNOWLEDGE: The present study compares, by means of validated geometric indexes, manual segmentations of axillary lymph nodes in breast cancer from different observers and different institutions made on radiotherapy planning CT images. Assessing such variability is of paramount importance, as geometric uncertainties might lead to incorrect dosimetry and compromise oncological outcome.
AB - OBJECTIVES: To determine interobserver variability in axillary nodal contouring in breast cancer (BC) radiotherapy (RT) by comparing the clinical target volume of participating single centres (SC-CTV) with a gold-standard CTV (GS-CTV). METHODS: The GS-CTV of three patients (P1, P2, P3) with increasing complexity was created in DICOM format from the median contour of axillary CTVs drawn by BC experts, validated using the simultaneous truth and performance-level estimation and peer-reviewed. GS-CTVs were compared with the correspondent SC-CTVs drawn by radiation oncologists, using validated metrics and a total score (TS) integrating all of them. RESULTS: Eighteen RT centres participated in the study. Comparative analyses revealed that, on average, the SC-CTVs were smaller than GS-CTV for P1 and P2 (by -29.25% and -27.83%, respectively) and larger for P3 (by +12.53%). The mean Jaccard index was greater for P1 and P2 compared to P3, but the overlap extent value was around 0.50 or less. Regarding nodal levels, L4 showed the highest concordance with the GS. In the intra-patient comparison, L2 and L3 achieved lower TS than L4. Nodal levels showed discrepancy with GS, which was not statistically significant for P1, and negligible for P2, while P3 had the worst agreement. DICE similarity coefficient did not exceed the minimum threshold for agreement of 0.70 in all the measurements. CONCLUSIONS: Substantial differences were observed between SC- and GS-CTV, especially for P3 with altered arm setup. L2 and L3 were the most critical levels. The study highlighted these key points to address. ADVANCES IN KNOWLEDGE: The present study compares, by means of validated geometric indexes, manual segmentations of axillary lymph nodes in breast cancer from different observers and different institutions made on radiotherapy planning CT images. Assessing such variability is of paramount importance, as geometric uncertainties might lead to incorrect dosimetry and compromise oncological outcome.
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U2 - 10.1259/bjr.20201177
DO - 10.1259/bjr.20201177
M3 - Article
C2 - 33882239
AN - SCOPUS:85108742120
SN - 0007-1285
VL - 94
SP - 20201177
JO - British Journal of Radiology
JF - British Journal of Radiology
IS - 1123
ER -