AT THE NORTHWESTERN VASCULAR SYMPOSIUM
CHICAGO (FRONTLINE MEDICAL NEWS) – More than 53,000 people will develop pancreatic ductal adenocarcinoma in the United States this year, and upwards of 41,000 will die from the disease, many of them with tumors considered unresectable because they involve adjacent vessels. However, researchers at the University of California, Irvine, have found that careful removal of the tumor around involved veins and arteries, even in borderline cases, can improve outcomes for these patients.
Roy M. Fujitani, MD, updated previously published data on a single-center study he coauthored in 2015 of 270 patients who had undergone a Whipple operation, 183 for pancreatic adenocarcinoma ( J Vasc Surg. 2015;61:475-80 ) at a symposium on vascular surgery sponsored by Northwestern University.
“Pancreatic ductal adenocarcinoma continues to have a very poor prognosis and this is likely due to the early metastasis and late symptom presentation of our patients,” said Dr. Fujitani of the University of California, Irvine. “The Whipple operation with concomitant vascular reconstruction for borderline resectable T3 lesions with vascular invasion may allow for increased microscopic margin negative surgical resections, including in those patients receiving neoadjuvant therapy.”
Resection of pancreatic tumors without vascular involvement is fairly straightforward for surgical oncologists to perform, Dr. Fujitani said, but pancreatic tumors enter the borderline resectable category when preoperative CT scan shows portal vein abutment, for which vascular surgery should provide counsel and assist. However, even in some cases when preoperative CT scan shows unresectable, locally advanced pancreatic tumor with celiac artery encasement, neoadjuvant therapy may downstage the disease into the borderline category, he said.
“Patients with borderline resectable or stage II disease are those one should consider for reconstruction,” Dr. Fujitani said. Resectable findings of borderline disease include encasement of the portal vein, superior mesenteric vein and the confluence of the portal venous system (with suitable proximal and distal targets for reconstruction); and less-than-circumferential involvement of the common hepatic artery or right hepatic artery – but without involvement of the superior mesenteric artery or the celiac axis and “certainly not” the aorta. “This would account for about one-fourth of patients in high-volume centers as being able to receive concomitant vascular reconstruction,” Dr. Fujitani said.
If less than 20% of the portal venous system is involved, the tumor can be resected with part of the vessel followed by primary repair. “Our preference is to do a vein patch onto the vein,” he said. “The other option is to use an autologous conduit either from a vein harvested elsewhere or a prosthetic conduit.” His group prefers the former approach because of the risk of infection with prosthetic conduits. Another approach is to use cryopreserved vein allografts.
In the UCI series, 60 patients with borderline lesions underwent vascular reconstruction. “As it turned out, there was no significant difference in survival between the reconstruction group and the nonreconstruction group,” Dr. Fujitani said, “but it’s important to note that these patients who had the reconstruction would never have been operated on if we were not able to do the reconstruction.” Thirty-day mortality was around 5% and 1-year survival around 70% in both groups, he said. However, at about 1.5 years the Kaplan-Meier survival curves between the two groups diverged, which Dr. Fujitani attributed to more advanced disease in the reconstruction group.
“We found lymph node status and tumor margins were most important in determining survival of these patients,” he said. “Gaining an R0 resection is the most important thing that determines favorable survivability.”
Dr. Fujitani also reviewed different techniques for vascular reconstruction, and while differences in complication rates or 1-, 2-, or 3-year survival were not statistically significant, he did note that mean survival with lateral venorrhaphy exceeded that of primary anastomosis and interposition graft – 21 months vs. 13 months vs. 4 months, suggesting the merits of a more aggressive approach to vascular resection and reconstruction.
“Improvement of survival outcomes may be achieved with concomitant advanced vascular reconstruction in carefully selected patients,” Dr. Fujitani said. “There are multiple options for vascular reconstruction for mesenteric portal venous and visceral arterial involvement using standard vascular surgical techniques.” He added that a dedicated team of experienced surgical oncologists and vascular surgeons for these reconstructions “is essential for successful outcomes.”
Dr. Fujitani had no relevant financial relationships to disclose.