Postoperative results, learning curve, and outcomes of pancreatectomy with arterial resection: a single-center retrospective cohort study on 236 procedures

Abstract

Background: Newer chemotherapy regimens are reviving the role of pancreatectomy with arterial resection (PAR) in locally advanced pancreatic cancer. However, concerns about the early outcomes and learning curve of PAR remain. This study aimed to define the postoperative results and learning curve of PAR and provide preliminary data on oncologic outcomes.

Materials and methods: A single center's experiences (1993-2023) were retrospectively analyzed to define the postoperative outcomes and learning curve of PAR. Oncologic results were also reported.

Results: During the study period 236 patients underwent PAR. Eighty PAR (33.9%) were performed until 2012, and 156 were performed thereafter (66.1%). Pancreatic cancer was diagnosed histologically in 183 patients (77.5%). Induction therapy was delivered to 18 of these patients (31.0%) in the early experience and to 101 patients (80.8%) in the last decade ( P <0.0001). The superior mesenteric artery (PAR-SMA), celiac trunk/hepatic artery (PAR-CT/HA), superior mesenteric/portal vein, and inferior vena cava were resected in 95 (40.7%), 138 (59.2%), 189 (80.1%), and 9 (3.8%) patients, respectively. Total gastrectomy was performed in 35 (18.5%) patients. The 30-day mortality rate was 7.2% and 90-day mortality rate was 9.7%. The learning curve for mortality was 106 PAR [16.0 vs. 4.6%; odds ratio, OR=0.25 (0.10-0.67), P =0.0055]. Comparison between the PAR-SMA and PAR-CT/HA groups showed no differences in severe postoperative complications (25.3 vs. 20.6%), 90-day mortality (12.6 vs. 7.8%), and median overall survival. Vascular invasion was confirmed in 123 patients (67.2%). The median number (interquartile range) of examined lymph nodes was 60.5 (41.3-83) and rate of R0 resection was 66.1% (121/183). Median overall survival for PAR was 20.9 (12.5-42.8) months, for PAR-SMA was 20.2 (14.4-44) months, and for PAR-CT/HA was 20.2 (11.4-42.7). Long-term prognosis improved by study decade [1993-2002: 12.0 (5.4-25.9) months, 2003-2012: 15.1 (9.8-23.4) months, and 2013-present: 26.2 (14.3-51.5) months; P <0.0001].

Conclusions: In recent times, PAR is associated with improved outcomes despite a steep learning curve. Pancreatic surgeons should be prepared to face the technical challenge posed by PAR.

Figure 1

Study flow diagram.

Figure 2

Ninety-day postoperative mortality timeline in 236 pancreatectomy with arterial resection.

Figure 3

Incidence and severity of postoperative complications following superior mesenteric artery (PAR-SMA) (black bars) and celiac trunk/hepatic artery (PAR-CT/HA) (white bars).

Figure 4

Learning curve for postoperative mortality. A: All PAR; B: PAR-SMA; C: PAR-CT/HA.

Figure 5

A pancreatectomy specimen in 3 mm-thick slices along the axial plane perpendicular to the duodenal axis, showing the superior mesenteric artery (SMA), superior mesenteric vein (SMV) and common bile duct (CBD). B Whole mount histology macrosection stained with hematoxylin and eosin, showing the superior mesenteric artery (SMA), Wirsung duct (Wirsung) and common bile duct (CBD). C Hepatic artery histology (hematoxylin-eosin staining, original magnification: 2×). The artery shows no tumor infiltration but the distance between the external elastic lamina and tumor is only 488.17 micron. In this case, arterial divestment could result in a microscopically positive margin (i.e. R1 resection). D Superior mesenteric artery histology (hematoxylin-eosin staining, original magnification: 2×). The tumor invades the tunica adventitia (ADV), while sparing the external elastic lamina (EEL). E Superior mesenteric artery histology (hematoxylin-eosin staining, original magnification: 2×). The tumor invades the external elastic lamina (EEL). F Hepatic artery histology (hematoxylin-eosin staining, original magnification: 2×). The vessel is surrounded by the tumor, which causes lumen reduction and invades the adventitial (ADV), muscular (MUS), and intimal (INT) layers.

Figure 6

Kaplan–Meier survival curves (overall survival) of PAR (continuous line), PAR-CT/HA (long dash line), and PAR-SMA (dotted line) with pancreatic cancer histology results.