Does pancreas cyst size correlate with the risk for malignancy?

Context: Some studies have suggested that small pancreas cysts can be observed. Large cysts or those with increasing size may require intervention. Mucin-producing or malignant cysts have been suspected by increased cyst fluid viscosity, elevated fluid CEA level, imaging features, and cytopathology. Objective: The purpose of this analysis is to determine the actual correlation of pancreas cyst size and the presence of malignant or premalignant features. Design: Retrospective study of all consecutive pancreatic cysts that were referred for analysis by endoscopic ultrasound (EUS) over an 18 month period at a single center academic tertiary referral institution. Patients or Participants: A total of 65 cysts in 65 patients were examined (36 men, 29 women, mean age of 56.8 and 59.3 years, respectively). Main outcome measures: The diagnostic predictability of pancreas cyst size alone to identify mucin-producing or malignant cysts and all nonmucinous cysts based on cytopathology. Results: The mean 2D size of malignant or mucinous cysts was 9.88cm². The mean 2D size of all nonmucinous cysts was 16.4cm² but was not statistically significant (p=0.15). Pseudocysts tended to be larger and had a mean size of 22.5cm² and was statistically different in size from the malignant or mucinous cysts (p=0.044) as well as mean size of serous cysts (7.51cm², p=0.023). The difference in size between mucinous and serous cysts also was not statistically significant (p=0.62). Conclusions: Pseudocysts have a larger mean size than malignant or mucinous cysts as well as serous cysts. However, the parameter of cysts size alone does not aid in differentiating mucinous and nonmucinous cysts. Cyst fluid analysis is essential to determine the type of cyst and optimal management.