Centralization of Pancreaticoduodenectomy

Abstract

Objective: Through a systematic review and spline curve analysis, to better define the minimum volume threshold for hospitals to perform (pancreaticoduodenectomy) and the high volume centre (HVC). Summary Background Data: The pancreaticoduodenectomy (PD) is a resource intensive procedure, with high morbidity and long hospital stays resulting in centralization towards high-volume hospitals; the published definition of high-volume remains variable. Materials and Methods: Following a systematic review of studies comparing PD outcomes across volume groups, semiparametric regression modelling of morbidity (%), mortality (%), length of stay (days), lymph node harvest (number of nodes) and cost ($USD) as continuous variables was performed and fitted as a smoothed function of splines. If this showed a non-linear association, then a “zero-crossing” technique was used which produced “first and second derivatives” to identify volume thresholds. Results: Our analysis of 33 cohort studies (198,377 patients) showed 55 PDs/year and 43 PDs/year were the threshold value required to achieve lowest morbidity and highest lymph node harvest, with model estimated degrees of freedoms 5.154 (P<0.001) and 8.254 (P<0.001) respectively. The threshold value for mortality was approximately 45 PDs/year (model 9.219 (P <0.001)) with the lowest mortality value (the optimum value) at approximately 70 PDs/year (i.e. a high volume centre). No significant association was observed for cost (e.d.f=2, P=0.989), and length of stay (e.d.f=2.04, P=0.099). Conclusions: There is a significant benefit from centralization of PD, with 55 PDs/year and 43 PDs/year the threshold value required to achieve lowest morbidity and highest lymph node harvest respectively. To achieve mortality benefit, the minimum procedure threshold is 45 PDs/year, with the lowest and optimum mortality value (i.e. a high volume center) at approximately 70 PDs/year.