ASO Author Reflections: Prognostic Role of Preoperative Duke Pancreatic Monoclonal Antigen Type 2 Values in Patients with Pancreatic Cancer: Focusing on the Usefulness in Patients with Normal CA19-9.

Pancreatic cancer (PC) is one of the most aggressive cancer types, and carbohydrate antigen (CA) 19-9 has been the most useful biomarker for its surveillance and prognosis prediction. However, CA19-9 may not be sufficiently prognostic in some patients, such as Lewis antigen-negative phenotype (Le[a-b-]) patients who secrete little or no CA19-9. Duke pancreatic monoclonal antigen type 2 (DUPAN-2) has been proposed as a complementary marker to CA19-9 in PC patients, but its utility in Le(a-b-) patients has only been reported in a limited number of cases. In a retrospective analysis of 224 PC patients who underwent surgery, the present study investigated the utility of DUPAN-2 in combination with CA19-9. The study subjects were divided into three groups based on their CA19-9 and DUPAN-2 levels. The normal CA19-9/high DUPAN-2 group had significantly larger tumors and a higher frequency of microscopic vascular invasion, perineural invasion, and recurrence than the normal CA19-9/normal DUPAN-2 group. Both the disease-free survival and disease-specific survival (DSS) of patients in the normal CA19-9/high DUPAN-2 group were significantly shorter than those in the normal CA19-9/normal DUPAN-2 group, and comparable with those in the high CA19-9 group. The results suggest that DUPAN-2 may be useful as a complementary biomarker to CA19-9 in PC, especially in patients who have normal CA19-9 levels. However, since this was a single-center, retrospective study, multicenter studies are needed to confirm the findings and determine the optimal cut-off value for patients with normal CA19-9 levels.