While there is an ethical obligation to improve clinical outcomes by developing better therapies, surgical innovation has largely progressed without the strict regulations required of novel pharmaceutical products. We explore the reasons why new surgical techniques are frequently introduced without the benefit of randomised controlled trials, and present an approach to the ethical evaluation of novel surgical procedures.
Biomedical Research ; ethics ; Clinical Competence ; Diffusion of Innovation ; Ethics, Medical ; General Surgery ; ethics ; methods ; standards ; Humans ; Informed Consent ; Medical Audit ; Medicine ; Singapore ; Specialty Boards

INTRODUCTIONThis study aims to determine if the quantitative method of region-of-interest (ROI) analysis of lesion attenuation on CT may be a useful adjunct to the conventional approach of diagnosis by visual assessment in assessing tracer wash-out in hepatocellular carcinomas.

MATERIALS AND METHODSFrom a surgical database of 289 patients from 2 institutions, all patients with complete surgical, pathological and preoperative multiphasic CT scans available for review were selected. For each phase of scanning, HU readings of lesion obtained (Lesion(arterial), Lesion(PV) and Lesion(equilibrium)) were analysed using receiver operating curves (ROC) to determine the optimal method and cut-off value for quantitative assessment of tumour wash-out (Lesion(arterial - equilibrium), Lesion(PV - equilibrium) or Lesion(peak - equilibrium)).

RESULTSNinety-four patients with one lesion each met the inclusion criteria. The area under the curve (AUC) values for Lesion(arterial - equilibrium) (0.941) was higher than the AUC for Lesion(pv - equilibrium) (0.484) and for Lesion(peak - equilibrium) (0.667). Based on ROC analysis, a cut-off of 10HU value for Lesion(arterial - equilibrium) would yield sensitivity and specificity of 91.5% and 80.9%, respectively. ROI analysis detected 9/21 (42.9%) of lesions missed by visual analysis. Combined ROI and visual analysis yields a sensitivity of 82/94 (87.2%) compared to 73/94 (77.7%) for visual analysis alone.

CONCLUSIONUsing a cut-off of 10 HU attenuation difference between the arterial and equilibrium phases is a simple and objective method that can be included as an adjunct to visual assessment to improve sensitivity for determining lesion wash-out on CT.

Adult ; Aged ; Aged, 80 and over ; Carcinoma, Hepatocellular ; diagnosis ; pathology ; surgery ; Confidence Intervals ; Databases, Factual ; Female ; Humans ; Liver ; pathology ; Liver Neoplasms ; diagnosis ; pathology ; surgery ; Male ; Middle Aged ; Preoperative Period ; ROC Curve ; Retrospective Studies ; Sensitivity and Specificity ; Tomography, X-Ray Computed ; instrumentation ; Young Adult