O-L03 Safety and Efficacy of Endoscopic Retrograde Cholangiopancreatography for Removal of Common Bile Duct Stones in the Nonagenarians: A Single Tertiary Centre Experience

nosis of peri-hilar cholangiocarcinoma. The objective of this study was to evaluate the utility of these models in determining prognosis for all patients presenting to a tertiary treatment centre with PHC. Methods: Three hundred and two patients diagnosed with PHC referred to a regional tertiary referral centre between 2008 and 2019 had their demographic and survival data retrospectively analysed from a prospectively held database linked to Hospital Episode Statistics and Somerset Cancer Registry data. One hundred and twenty seven patients were surgically explored. Eight-four patients underwent resection. One-hundred and seventy-four (57.6%) patients underwent palliative endoscopic therapy. Univariate and multivariate modelling was utilised to determine significant prognostic variables. Concordance Indices (C-Indices) were constructed for the prognostic models to determine internal validity within the cohort. Results: Multivariate analysis demonstrated that: pre-interventional ECOG status (p< 0.001); serum albumin (p< 0.001); bilirubin levels (p<0.001); CA 19-9 levels (p< 0.001) and resectional status (p< 0.001) were significant predictors of OS. Patients stratified by the MC scoring system to early-stage disease had a significantly longer OS compared to patients fulfilling late-stage criteria (p< 0.001). The predictive CIndices for the MC model obtained significance in discriminating OS for the entire cohort (p< 0.05) and un-resected patients (p< 0.05). Neither model attained significant concordance for accurately discriminating OS in post-resectional patients. Conclusions: The predictive performance of the stated prognostic models for OS have poor utility. Simple pre-interventional serological, functional and radiological variables appear to provide better prognostic indication of OS. Variables not incorporated in the AJCC registry have a significant effect upon post-resectional OS and require full incorporation in to model prognostication.