Clinical characteristics and treatment analysis of pancreatic acinar cell carcinoma: A single institutional comparison to pancreatic ductal adenocarcinoma.

Abstract

BACKGROUND\nPancreatic acinar cell carcinoma (PACC) is a rare malignancy that accounts for less than 1% of primary pancreatic neoplasms. Currently, the lack of large-scale clinical studies limits our understanding of PACC. The aim of this study was to investigate the clinical characteristics and prognosis of PACC.\n\n\nMETHODS\nIn a retrospective analysis, 52 patients with PACC and 355 patients with pancreatic ductal adenocarcinoma (PDAC) who underwent surgical interventions were evaluated. Clinical characteristics and treatment outcomes were compared between the two groups.\n\n\nRESULTS\nThe mean age was lower for patients with PACC than for those with PDAC (mean: 50.8\xa0±\xa010.9 versus 59.4\xa0±\xa010.9 years; p\xa0<\xa00.001). Except for alpha-fetoprotein (AFP), tumour markers were also lower in the PACC group than the PDAC group. In regard to tumour characteristics, maximum diameters of the primary tumour [median (range): 5.0\xa0cm (1.0-18.2\xa0cm) versus 3.5\xa0cm (0.6-15.0\xa0cm); p\xa0<\xa00.001] and hepatic metastatic lesions [6.7\xa0cm (1.5-12.6\xa0cm) versus 1.2\xa0cm (0.3-3.3\xa0cm); p\xa0<\xa00.001] were larger in patients with PACC than patients with PDAC, but vascular invasion [23.1% (12/52) versus 35.5% (126/355); p\xa0=\xa00.044] and perineural invasion [7.7% (4/52) versus 56.1% (199/355); p\xa0<\xa00.001] were more common in patents with PDAC than in patients with PACC. For treatment, radical resection was performed in 57.7% of patients with PACC, which increased the 5-year survival rate to 31.8%. In regard to prognosis, the 5-year survival rate was 21.4% for PACC and 9.7% for PDAC (p\xa0<\xa00.0001).\n\n\nCONCLUSIONS\nPACC is more indolent than PDAC, which makes early diagnosis more difficult. Although the stage may be advanced at diagnosis, the overall survival (OS) of PACC is much better than that of PDAC, and the prognosis greatly improves after radical resection.