Rapid, intense pericholedochal fibrosis after preoperative biliary drainage: A prospective histologic study in...

Preoperative biliary drainage (PBD) is commonly used prior to pancreatoduodenectomy (PD), but its histologic effects on the extrahepatic bile duct are not well understood in humans. This study aimed to prospectively measure pericholedochal fibrosis (PCF) in PD specimens after plastic biliary stenting to assess its extent and clinical significance.

Consecutive patients undergoing PD were divided into two groups: those who received PBD (n = 22) and non-drained controls (n = 24). Patients who had neoadjuvant chemotherapy were excluded to focus on stent-related effects. Common bile duct (CBD) specimens were analyzed using standardized Masson's trichrome staining. Digital morphometry quantified CBD dimensions, collagen area, and collagen density. Histologic markers were correlated with stent dwell time and surgical outcomes.

PBD was linked to a substantial increase in PCF. Stented ducts showed significantly greater wall thickness (6,554 vs. 499 μm; p < 0.001), total collagen area (p < 0.001), and collagen density (p < 0.001) compared to controls. Fibrosis developed rapidly, becoming clearly evident by day 6, with no significant correlation between collagen burden and stent dwell time (median 10 days). Despite these pronounced histologic changes, operative time (230 vs. 230 minutes; p = 0.98) and postoperative complication rates did not differ significantly between the groups.

Short-term PBD with plastic stents causes rapid, intense, and persistent PCF that stabilizes soon after stent placement. Although this fibrotic response did not negatively impact surgical outcomes at a high-volume center, the findings underscore the significant tissue remodeling triggered by stenting and advocate for the careful use of PBD.