Surgical and oncological impact of main pancreatic duct spread in invasive ductal adenocarcinoma: A clinicopathological study of 184 resected cases

Abstract

Background/objectives: This study examined main pancreatic ductal spread in invasive ductal adenocarcinoma (IDC) of the pancreas.

Methods: Data from IDC patients who underwent radical surgery from 1990 to 2013 in our hospital were examined retrospectively. Incidence of intraductal spread of pancreatic cancer (IS), distance from the tumor edge, direction of IS and clinicopathological factors associated with the presence of IS were retrospectively examined with data from IDC patients who underwent radical surgery.

Results: Among 260 IDC patients who underwent surgery, 184 eligible cases, IS was identified in 42 patients (22.8%) and mean length of IS was 18.7 ± 21.6 mm. Mean distances on the ampullary and distal sides of IS were 11.1 mm and 11.6 mm. IS was significantly more frequent in localized tumors (UICC T1-2 vs. 3-4, p = 0.007), with tumor diameter ≤2 cm (p = 0.034) and in cases with scarce microscopic perineural invasion (p = 0.047). Among patients who underwent pancreaticoduodenectomy and distal pancreatectomy, IS presence (11.6 vs. 21.8%), mean distance to the contralateral side (11.4 vs. 11.6 mm), and IS ≥ 2 cm (3.3 vs. 4.7%) showed no significant differences. Overall survival did not differ significantly between IS-positive and -negative patients in the full analysis set or propensity score-matched patients (42 matched pairs).

Conclusions: In setting resectional margins at 2 cm, a small proportion of cases (3.8%) showed positive surgical margins. Localized tumor (UICC: T1-2, or <2 cm in diameter) requires more care with surgical margins, warranting intraoperative frozen sections.

Keywords: Intraductal carcinoma; Intraductal spread; Pancreatic cancer; Pancreatic ductal carcinoma; R0; Surgical margin.