KRAS Mutation Analysis Using Cell-free DNA of Pancreatic Cancer

Abstract

Background/aim: Detection of pancreatic cancer using small samples of the pancreas obtained by endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) remains a challenge. The purpose of this study was to investigate whether the detection of KRAS mutations in cell-free DNA (cfDNA) extracted from supernatants of liquid-based fixed cytology (LBC) specimens obtained using EUS-FNA in solid pancreatic cancer can be an auxiliary test for differential diagnosis. The purpose of this study was to investigate whether the detection of KRAS mutations in cell-free DNA (cfDNA) extracted from supernatants of liquid-based fixed cytology (LBC) specimens obtained using EUS-FNA in solid pancreatic cancer can be an auxiliary test for differential diagnosis.

Patients and methods: This was a single-institution cohort study that included 50 patients with pancreatic lesions. cfDNA was isolated from the supernatant of fixed LBC samples, and KRAS mutation status was compared between cfDNA samples and FFPE small fragment tissues.

Results: Of the 50 cfDNA samples, 84% (42/50) were valid. KRAS mutations were detected in 57.1% (24/42) of the 42 valid samples. The sensitivity, specificity, and accuracy of KRAS mutation detection using cfDNA samples in the pancreatic lesions were 63.2% (24/38), 100.0% (4/4), and 66.7% (28/42), respectively. KRAS mutation status between FFPE small tissues and cfDNA samples were comparable.

Conclusion: Gene mutation analysis using cfDNA from the supernatant of fixed LBC samples is an effective ancillary diagnostic tool for pancreatic cancer.

Keywords: KRAS mutation; Pancreatic cancer; cytology cell-free DNA; endoscopic ultrasound-guided fine-needle aspiration cytology; liquid-based cytology.