This study aims to compare the efficacy and satisfaction of blood glucose management between continuous glucose monitoring versus traditional self blood glucose measurement in diabetic patients after pancreatectomy.

Patients will be enrolled after the 75g oral glucose tolerance test performed 7 days after pancreatectomy. Patients will be divided into two groups by randomization (continuous glucose measurement method vs. traditional self blood glucose measurement method), and 3months after surgery, HbA1c, hypoglycemic events, and satisfaction would be compared.

Inclusion Criteria:

• Patients over 19 years of age
• Preoperative diabetes history
• Patients who underwent subtotal or total pancreatectomy
• Patients who were diagnosed with diabetes mellitus in the evaluation of endocrine function test on the 7th day after pancreaticoduodenectomy, central pancreatectomy, or distal pancreatectomy

Exclusion Criteria:

• Patients who have used continuous blood glucose measurement device more than once before.
• Elderly patients who are not accustomed to using the smartphone applications
• Serious systemic diseases that can affect diabetes (chronic kidney disease, heart failure, decompensated liver cirrhosis, etc.)
• Steroid user during the study period
• Major medical or psychiatric condition that will affect response to treatment