Pancreatic cyst fluid harboring a KRAS mutation

Area of Science:

• Gastroenterology
• Oncology
• Molecular Diagnostics

Background:

• Pancreatic cysts pose diagnostic challenges, with mucinous cystic neoplasms requiring careful evaluation for malignancy.
• Endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) is crucial for pancreatic cyst fluid analysis.
• Accurate classification of pancreatic cysts is essential for appropriate patient management.

Observation:

• A 55-year-old woman presented with abdominal bloating and imaging revealed a pancreatic cyst with ductal dilation.
• EUS-FNA yielded cyst fluid initially suggestive of a mucinous neoplastic cyst, with indeterminate malignancy potential.
• Rapid KRAS mutation analysis of cyst fluid using the Idylla system detected a KRAS G12D mutation.

Findings:

• Histopathological examination of the resected specimen confirmed an intraductal papillary mucinous neoplasm (IPMN) with invasive carcinoma.
• KRAS G12D mutation analysis on the resected tumor tissue correlated with the cyst fluid findings.
• The Idylla system provided rapid and accurate KRAS mutation detection directly from pancreatic cyst fluid.

Implications:

• Direct KRAS mutation testing from pancreatic cyst fluid can enhance the diagnostic accuracy of mucinous cystic lesions.
• This molecular approach complements traditional cytology, especially in non-diagnostic cases.
• Improved classification of pancreatic cysts may lead to more timely and appropriate therapeutic interventions.