Inter-observer agreement in assessment of clinically overt extra nodal
extension (cN3b)
Abstract
Key Points • Clinical N3b staging is defined as unequivocal and
unambiguous signs of extra nodal extension (ENE), such as skin
involvement, muscle invasion or nerve dysfunction, supported by
radiological evidence. • There is a paucity of studies determining
interobserver reliability of clinical detection of overt ENE. • A
prospective comparative cohort study assessing 12 Head and Neck
surgeons’ inter-observer agreement in detecting the components of overt
ENE. • We reveal high surgeon agreement in the ability to detect lymph
nodes, the presence of skin involvement and in surrounding nerve
involvement. • Variability of surgeon assessment was seen in the
assessment of overt muscular involvement.