Observer Agreement In Single Computerized Tomography Use For Diagnosing Paediatric Head And Neck Malignancies At A National Oncology Centre

Abstract BackgroundThe increase in the prevalence of paediatric head and neck malignancies (PHNM) has led to increased use of computerized tomography (CT), an ionizing radiation source. Children are at a risk of up to ten times more for radiation induced secondary malignancies. In the Ugandan setting, investigation for PHNM with CT uses a protocol with both unenhanced and contrast enhanced procedures hence doubling the ionizing radiation exposure. The purpose of this study was to determine the feasibility of single CT procedures in diagnosing PHNM.MethodsThis was a cross-sectional study using CT images from patients, aged fifteen years and below, investigated for head and neck malignancies at the Uganda Cancer Institute. Three radiologists; observer A, observer B and observer C, with 12, 5 and 2 years of experience, respectively, participated in the study. They independently reported contrast enhanced images (protocol A), unenhanced images (protocol B), then both unenhanced and contrast enhanced images (protocol C) in two months intervals. Gwen’s Agreement coefficient was used to determine intra- and inter-observer agreement.ResultsSeventy-three CT scans of 36 boys and 37 girls, with a median age of 9 (3-13) years, were used. Intra-and inter-observer agreement on primary tumour location ranged from substantial to almost perfect with the highest intra-observer agreement observed when protocols A and C were compared. Inter-observer agreement for tumour calcifications was substantial for protocol A. Observers A and C demonstrated an almost perfect intra-observer agreement when protocols A and C were compared. There was a substantial inter-observer agreement on diagnosis for all protocols. ConclusionsDouble CT procedures for diagnosis of PHNM do not show a significant advantage over the use of contrast enhanced single CT procedures. Contrast enhanced CT only procedures are sufficient in identifying presence of tumor calcifications when diagnosing PHNM.