Cystic lesions of the pancreas: changes in the presentation and management of 1,424 patients at a single institution over a 15-year time period

Abstract

Background: Cystic lesions of the pancreas are being identified more frequently, and a selective approach to resection is now recommended. The aim of this study was to assess the change in presentation and management of pancreatic cystic lesions evaluated at a single institution over 15 years.

Study design: A prospectively maintained registry of patients evaluated between 1995 and 2010 for the ICD-9 diagnosis of pancreatic cyst was reviewed. The 539 patients managed from 1995 to 2005 were compared with the 885 patients managed from 2005 to 2010.

Results: A total of 1,424 patients were evaluated, including 1,141 with follow-up >6 months. Initial management (within 6 months of first assessment) was operative in 422 patients (37%) and nonoperative in 719 patients (63%). Operative mortality in patients initially submitted to resection was 0.7% (n = 3). Median radiographic follow-up in patients initially managed nonoperatively was 28 months (range 6 to 175 months). Patients followed radiographically were more likely to have cysts that were asymptomatic (72% versus 49%, p < 0.001), smaller (1.5 versus 3 cm, p < 0.001), without solid component (94% versus 68%, p < 0.001), and without main pancreatic duct dilation (88% versus 61%, p < 0.001). Changes prompting subsequent operative treatment occurred in 47 patients (6.5%), with adenocarcinoma identified in 8 (17%) and pancreatic endocrine neoplasm in 4 (8.5%). Thus, of the 719 patients initially managed nonoperatively, invasive malignancy was identified in 12 (1.7%), with adenocarcinoma seen in 1.1%.

Conclusion: Cystic lesions of the pancreas are being identified more frequently, yet are less likely to present with concerning features of malignancy. Carefully selected patients managed nonoperatively had a risk of malignancy that was equivalent to the risk of operative mortality in those patients who initially underwent resection.

Figure 1

The number of patients evaluated each year for a cystic lesion of the pancreas (blue bars), and the median size (red line) of the lesion at initial visit (1995-2010, n=1,424).

Figure 2

Diagnostic tests used in evaluating 1,424 patients with cystic lesions of the pancreas (1995-2010, n=1424).

Figure 3

(A) First and second node of decision tree analysis for the selection of initial operative management in the 539 patients evaluated for a pancreatic cyst. (B) First and second node of decision tree analysis for the selection of initial operative management in the 885 patients evaluated for a pancreatic cyst from 2005 to 2010.

Figure 4

(A) Likelihood of resection in patients initially followed radiographically (n=719) according to whether the cyst was < or ≥ 2 cm at initial presentation (Kaplan-Meier method). (B) Risk of death from causes other than pancreatic cancer and (C) risk of death from pancreatic cancer in those patients initially selected for non-operative management (Kaplan-Meier method).