80 Long-Term Follow-Up of Patients With Pancreatic Cystic Lesions Who Had No Significant Changes in the First 5 Years of Diagnosis

Abstract

INTRODUCTION: Discontinuation of surveillance after 5 years for pancreatic cystic lesions (PCL) without significant changes remains controversial. Long-term outcomes of patients with PCL with no significant changes in the first 5 years were evaluated. METHODS: We performed a retrospective analysis of patients with PCL diagnosis from 2005 to 2011 with follow-up until 2017. Significant changes were defined as the history of pancreatic cancer, pancreatectomy, high risk stigmata (HRS), worrisome features (WF) and worrisome EUS features (WEUS). Details of HRS, WF, WEUS in Table 1. RESULTS: Of 1551 patients with the diagnosis of PCL, 984 had no significant changes in the first 5 years. Range of follow-up was 5–13 years (190 patients >10 years). Median (Q1–Q3) cyst size at initial imaging was 12 (9–17) mm; maximum cyst size in first 5 years and post 5 years were 13 (9–18) mm and 15 (10–22) mm, respectively. 4 patients developed pancreatic cancer (0.41%; at 80, 97, 70, and 103 months). 7 (0.71%), 99 (10%), 5 (0.51%) patients developed HRS, WF, WEUS, respectively. Median (Q1–Q3) time to cancer, HRS, WF, and WEUS were 88.7 (75.3–100), 97.2 (66–109.6), 78.2 (72.5–97.9), 77 (68–104) months, respectively. Patients with CSO/clinically significant outcomes (defined as pancreatic cancer, HRS, WF, WEUS) post 5 years had larger maximum cyst size in the first 5 years compared to those without CSO [median (Q1–Q3) 16 (12–23) vs 12 (9–17) mm, P = 0.0001] (Figure 1). 152 patients died post 5 years (3 due to pancreatic cancer). The incidence of pancreatic cancer and CSO at 7 years post 5-year period (12 years from PCL diagnosis) in patients with no significant changes were 0.7% and 12.5%, respectively. The mortality due to pancreatic cancer was 0.45%; mortality due to all causes was 31.7%. Median (range) of Charlson Comorbidity Index (CCI) was 2 (0–16) at 5 years post PCL diagnosis. The mortality rate at 7 years post 5-year period for ACCI (age-adjusted CCI) of ≤3, 4–6, and ≥7 were 3.5%, 28% and 58% (P < 0.0001), respectively (Figure 2). CONCLUSION: The incidence of pancreatic cancer in patients with PCL with no significant changes in the first 5 years of diagnosis remains low at 0.7%. The incidence of clinically significant outcomes (CSO) was higher at 12.5%. Maximum cyst size of ≥15 mm in the first 5 years had higher cumulative incidence of CSO in long-term follow-up. These risks should be weighed against patients' overall mortality (based on scoring systems such as CCI) when making surveillance decision of PCL beyond 5 years.