Periodic follow-up of pancreatic cysts for early detection of pancreatic cancer

Objectives: This study aims to clarify the ideal follow-up method for early detection of Pancreatic ductal adenocarcinoma (PDAC). Methods: Our pancreatic cyst clinic was established for the follow-up of patients with pancreatic cysts. Imaging tests and blood tests are performed every six months. This study retrospectively examined the incidence of PDAC during follow-up in 680 patients treated at the cyst clinic from September 2016 to December 2020. Results: Patients included 588 with IPMN, 82 with unclassifiable cysts, and 10 with others. Seven patients with IPMN developed PDAC, and 6 underwent surgical resection. PDACs were pathological Stage I for 5 patients and Stage II for 1. Another one was unresectable due to liver metastases. The number of patients whose pancreatic mass were visualized by EUS / CT / MRI were 7 / 5 / 4 respectively. There was only one patient whose mass was visualized by EUS only. Intervals before detection of PDAC were 9 months for 1 patient, 7 for 1, 6 for 4, and 4 for 1. Any examinations before the cancer diagnoses could not detect the PDAC. Conclusion: Periodic follow-up of patients with pancreatic cystic lesions almost within 6 months can contribute to diagnosis of PDAC at an early stage. Although annual EUS is preferable modality to confirm pancreatic mass, other modalities may be substitutive for elderly or frail patient.