External validation of the Japanese difficulty scoring system for minimally-invasive distal pancreatectomies

Preoperative prediction of the difficulty of surgery would be useful for surgeons embarking on MIDP. A novel difficulty scoring system(DSS) was recently developed in Japan but has not been externally validated. This study aims to externally validate the DSS determine its association with important clinical outcome parameters.

Retrospective review of 90 patients who underwent MIDP from 2006 to 2018. The patients were stratified into 3 groups (low, intermediate and high difficulty) according to the DSS with some minor modifications.

Difficulty of MIDP was classified as low in 45(50%), intermediate in 32(35.5%) and high in 13(14.4%). Comparison between the baseline characteristics across the 3 difficulty groups demonstrated a significant difference in the frequency of malignant tumors, larger tumor size, frequency of extended pancreatectomies and use of robotic assistance. There was statistically significant increase in operation time, blood loss and blood transfusion rate across the 3 groups from low to high difficulty.

The DSS correlated significantly with operation time, blood loss and blood transfusion rate. These findings support the validity of the system.