TY - JOUR
T1 - Inter- and intra-observer variability in the classification of extracapsular extension in p16 positive oropharyngeal squamous cell carcinoma nodal metastases
AU - Lewis, James S.
AU - Tarabishy, Yaman
AU - Luo, Jingqin
AU - Mani, Haresh
AU - Bishop, Justin A.
AU - Leon, Marino E.
AU - Prasad, Manju L.
AU - Xu, Haodong
AU - Di Palma, Silvana
N1 - Publisher Copyright:
© 2015 Elsevier Ltd.
PY - 2015/11
Y1 - 2015/11
N2 - Summary Objective Discern inter- and intra-observer variability in the classification of extracapsular extension (ECE) in p16+ oropharyngeal (OP) SCC comparing pathologists' own criteria versus those of a well-defined classification system. Methods Five pathologists reviewed 50 digitally scanned nodal metastasis slides in three Rounds. Round One was by their own criteria as ECE present or absent, and Rounds Two and Three were with a defined ECE system: Grade 0 (no ECE), 0c (no ECE - thick capsule; no infiltration), 1 (ECE - cells beyond capsule), and 2 (soft tissue metastasis - cells in soft tissue without residual node). Round Three assessed intra-observer variability after an 8 month washout period. Results In Round One, all five agreed on only 48% of cases (n = 24). Fleiss's Kappa value was 0.508 (95% CI: 0.357-0.644). For Rounds Two and Three, Grades 0 and 0c and Grades 1 and 2 were separately grouped as ECE absent or present. In Round Two, all five agreed on 68% of cases (n = 34). Fleiss' Kappa was 0.635 (95% CI: 0.472-0.783), indicating statistically significantly better agreement. In Round Three, all five agreed on 64% of cases (n = 32) giving a Fleiss's Kappa of 0.639. Pathologists agreed with their prior reads in approximately 90% of cases (average n = 45.4, range n = 42-49), an average intra-observer Cohen's Kappa of 0.8 (range: 0.68-0.95). Inter- and intra-observer variability rates for classification of soft tissue metastasis (ECE2) were substantially worse. Conclusion There is substantial inter-, and modest intra-, observer variability among head and neck pathologists for ECE in p16+ OPSCC, which is modestly improved by a defined system.
AB - Summary Objective Discern inter- and intra-observer variability in the classification of extracapsular extension (ECE) in p16+ oropharyngeal (OP) SCC comparing pathologists' own criteria versus those of a well-defined classification system. Methods Five pathologists reviewed 50 digitally scanned nodal metastasis slides in three Rounds. Round One was by their own criteria as ECE present or absent, and Rounds Two and Three were with a defined ECE system: Grade 0 (no ECE), 0c (no ECE - thick capsule; no infiltration), 1 (ECE - cells beyond capsule), and 2 (soft tissue metastasis - cells in soft tissue without residual node). Round Three assessed intra-observer variability after an 8 month washout period. Results In Round One, all five agreed on only 48% of cases (n = 24). Fleiss's Kappa value was 0.508 (95% CI: 0.357-0.644). For Rounds Two and Three, Grades 0 and 0c and Grades 1 and 2 were separately grouped as ECE absent or present. In Round Two, all five agreed on 68% of cases (n = 34). Fleiss' Kappa was 0.635 (95% CI: 0.472-0.783), indicating statistically significantly better agreement. In Round Three, all five agreed on 64% of cases (n = 32) giving a Fleiss's Kappa of 0.639. Pathologists agreed with their prior reads in approximately 90% of cases (average n = 45.4, range n = 42-49), an average intra-observer Cohen's Kappa of 0.8 (range: 0.68-0.95). Inter- and intra-observer variability rates for classification of soft tissue metastasis (ECE2) were substantially worse. Conclusion There is substantial inter-, and modest intra-, observer variability among head and neck pathologists for ECE in p16+ OPSCC, which is modestly improved by a defined system.
KW - Extracapsular extension
KW - Inter-observer variability
KW - Lymph node metastasis
KW - Oropharyngeal squamous cell carcinoma
KW - Soft tissue metastasis
KW - p16
UR - http://www.scopus.com/inward/record.url?scp=84945454326&partnerID=8YFLogxK
U2 - 10.1016/j.oraloncology.2015.08.003
DO - 10.1016/j.oraloncology.2015.08.003
M3 - Article
C2 - 26293844
AN - SCOPUS:84945454326
SN - 1368-8375
VL - 51
SP - 985
EP - 990
JO - Oral Oncology
JF - Oral Oncology
IS - 11
ER -