Common Hepatic Artery Abutment or Encasement Is an Adverse Prognostic Factor in Patients with Borderline and Unresectable Pancreatic Cancer.

Background: Localized and unresectable pancreatic ductal adenocarcinoma (PDA) comprises one third of new diagnoses and includes borderline resectable (BR) and locally advanced (LA) unresectable disease. In a cohort of patients who were treated and followed at a single institution, we assessed clinical and radiographic predictors of outcome.

Methods: The study included 69 consecutive patients with BR or LA PDA. Serial imaging studies were reviewed by both a pancreatic surgeon and a radiologist for vascular abutment or encasement by cancer, and they were recorded.

Results: The cohort included 25 patients with BR and 44 patients with LA PDA, with median overall survivals (OS) of 15 and 14 months, respectively (p = 0.802). Fifteen patients were resected (22%), with a median OS of 21 months from diagnosis (HR 2.50, p = 0.006) and 13 months from resection. Median OS from diagnosis was 33 months in patients without lymph node metastases at resection (n = 10), but just 17 months with lymph node metastases (n = 5, HR = 8.95, p = 0.011). There were 12 two-year survivors in the total cohort (17%), and seven of them never underwent resection. First-line treatments consisted of gemcitabine (n = 13), modern first-line combinations (FOLFIRNOX or gemcitabine/nab-paclitaxel, n = 24), or alternative multi-agent therapies (n = 32); there were no statistical differences between treatment subgroups (OS of 10, 13, and 16 months, respectively). Common hepatic artery (CHA) abutment or encasement at diagnosis was associated with poor survival (adjusted hazard ratio, CHA abutment = 2.47 (p = 0.015) and CHA encasement = 2.16 (p = 0.036)).

Conclusion: In this cohort, common hepatic arterial abutment or encasement and residual lymph node disease at resection portended a particularly poor outcome in patients with localized, unresectable PDA.