Thick Pancreas, Dense Duct Branching, and Limited Fibrosis as Risk Factors for Pancreatic Fistula After Distal Pancreatectomy

Background The reported incidence of pancreatic fistula (PF) after distal pancreatectomy (DP) ranges from 10–40%. Identifying risk factors for PF may allow individualized modification of surgical techniques and postoperative management strategies. This study aimed to elucidate the clinico-histopathological characteristics associated with PF after DP. Methods A total of 186 patients who underwent DP were investigated. Pancreatic thickness at the planned transection site was measured using preoperative computed tomography. Histopathological findings of the pancreatic stump, including branched pancreatic duct (BPD) density and fibrosis ratio, were assessed quantitatively using morphometric analysis. Risk factors for PF were analyzed. Results The incidence of PF was 33%. Independent risk factors for PF included pancreatic thickness ≥ 11.7 mm (risk ratio [RR] 3.736; p < 0.001), BPD density ≥ 2.5/mm² (RR 5.173; p < 0.001), and fibrosis ratio < 4.4% (RR 2.596; p = 0.041). Patients with pancreatic thickness ≥ 11.7 mm demonstrated higher BPD density (2.5 vs. 1.8/mm²; p = 0.002) and lower fibrosis ratio (3.2% vs. 3.6%; p = 0.022). Conclusion Greater pancreatic thickness, dense duct branching, and low fibrosis ratio at the transection site were shown as significant risk factors for PF after DP. As high BPD density and low fibrosis ratio were both associated with a thick pancreas, these factors likely represent intrinsic physiological contributors to PF.