[394] The Role of Cytopathology in the Diagnosis and Management of Pancreatic Cysts Greater Than 3 cm

I Chebib, K Yeager, M Mino-Kenudsen, W Brugge, MB Pitman. Massachusetts General Hospital, Harvard Medical School, Boston, MA

Background: The role of cytology in pre-operative evaluation of pancreatic cysts is controversial. Recent guidelines recommend cysts greater than 3 cm be resected without cytologic diagnosis. In this study we evaluate the usefulness of cytology in the diagnosis and management of pancreatic cysts greater than 3 cm.
Design: The study cohort consists of resected pancreatic cysts greater than 3 cm between 2003-2007. Clinical, radiologic and pathologic information was evaluated and a multimodal approach was used to pre-operatively triage cysts for resection. Cysts not needing resection required either 1) benign lesional epithelium or 2) cyst contents without an epithelial component AND no atypical features on EUS (no thick cyst wall, invasion, mural nodule or dilated main pancreatic duct) AND CEA either greater than 192 ng/ml (consistent with a neoplastic mucinous cyst) OR an elevated amylase and low CEA (consistent with a pseudocyst or serous cyst). A cyst needing resection required at least atypical cells consistent with a mucinous cyst with moderate dysplasia or malignant epithelium. Cases were considered non-diagnostic if the fluid contained no epithelial cells, no radiologic information on the cyst was available or CEA was not analyzed. Cyto-histological and statistical analysis was performed.
Results: There were 105 resections of pancreatic cysts larger than 3 cm, 69 females (average age 53.4 years) and 36 males (average age 66.5 years). Thirty-one cysts (29.5%) had prior FNA, 21 females (average age 55.0 years) and 10 males (average age 67.4 years). When compared to histology, excluding six non-diagnostic cases, there were 9 true negatives, 10 true positives, 6 false negatives and 0 false positives. The sensitivity, specificity, positive predictive value and negative predictive value were 62.5%, 100%, 100%, and 60.0% respectively. Seventy-four (70.5%) cysts did not have prior FNA, 48 females (average age 52.6) and 26 males (average age 66.1). Of these cases, 38 (51.4%) were unnecessarily resected and 36 (48.6%) had moderate dysplasia or malignancy.
Conclusions: Patient management based on pancreatic cyst size results in unnecessary surgery in half of patients with pancreatic cysts > 3cm. The combination of cytology, radiology and cyst fluid analysis appropriately triages patients for surgery with high specificity and a PPV of 100%.
Category: Cytopathology

Wednesday, March 24, 2010 1:00 PM

Poster Session VI # 43, Wednesday Afternoon

 

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