Acinar cell carcinoma of the pancreas: a rare disease with different diagnostic and therapeutic implications than ductal adenocarcinoma.

Purpose: Acinar cell carcinoma (ACC) of the pancreas is a very rare cancer, constituting 1 % of all malignant non-endocrine pancreatic tumors. Only very limited data exist to guide treatment in patients with advanced ACC.

Methods: Between 2000 and 2015, 15 patients with ACC were diagnosed and/or treated at our high-volume comprehensive cancer center. Medical records and correlating serum levels of the potential serum tumor markers CA 19-9, CEA and lipase were analyzed retrospectively.

Results: A substantial antitumor activity was observed for treatment regimens containing 5-FU and oxaliplatin with partial responses or prolonged disease stabilizations (>12 months) observed in 6 out of 7 patients (86 %). Activity was also observed for single-agent 5-FU and its oral prodrugs. Serum lipase levels were elevated in 7 of 12 patients with advanced disease (58 %), whereas CEA and CA 19-9 seemed to be of minor importance for ACC (elevated pre-treatment levels in 4/12 and 3/12 cases, respectively). In selected patients, repeated serum lipase measurements were available and accurately predicted response to chemotherapy and relapse after surgery.

Conclusions: 5-FU- and oxaliplatin-containing regimens are active in advanced ACC. Lipase kinetics may be a useful novel tool to monitor the course of disease as well as treatment effects in ACC.