Next-generation sequencing adds value to the preoperative diagnosis of pancreatic cysts.

Abstract

BACKGROUND:

The diagnosis of a pancreatic cyst as mucinous or high-risk dictates the need for follow-up or surgery. Molecular analysis of aspirated pancreatic cyst fluid (PCF) can provide valuable information not obtained by carcinoembryonic antigen (CEA) analysis or cytology.

METHODS:

All patients who underwent molecular analysis of PCF between March 2013 and June 2015 were reviewed, including pathology, imaging, and follow-up. Molecular testing was performed using a patented, anchored multiplex polymerase chain reaction next-generation sequencing (NGS) platform, which sequenced numerous hotspots in 39 genes linked with malignancy. Performance of NGS and cytology was calculated using final outcome, as determined by clinicopathologic follow-up.

RESULTS:

The study cohort included 113 PCFs from 105 patients. In total, 119 variants were detected in 67 PCFs (59%). Variants were more common in intraductal papillary mucinous neoplasms (IPMNs)/cancer than in nonmucinous cysts (P < .005). The inclusion of v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS)/guanine nucleotide-binding protein (GNAS) variants improved the classification of IPMNs as mucinous from 50% by microscopy to 100%. Seventy-five percent of cancers had high-grade atypia versus 0% of IPMNs and nonmucinous cysts (P < .002). Variants in tumor protein 53 (TP53), SMAD family member 4 (SMAD4), cyclin-dependent kinase inhibitor 2A (CDKN2A), and notch1 (NOTCH1) were detected only in malignant cysts. Cytology was similarly specific (100%) for detecting malignant cysts but was more sensitive than the identification of late mutations by NGS (75% vs 46%).

CONCLUSIONS:

The detection of KRAS/GNAS variants improves the identification of mucinous neoplasms. Variants in TP53, SMAD4, CDKN2A, and NOTCH1 support the diagnosis of a high-risk cyst requiring surgery or additional sampling. Although molecular analysis is not a replacement for cytopathology, it does provide valuable information for accurate preoperative diagnosis, helping to classify mucinous neoplasms and high-risk cysts that require surgical resection. Cancer Cytopathol 2017;125:41-47. © 2016 American Cancer Society.

• Authors: Matthew W Rosenbaum, Martin Jones, Jonathan C Dudley, Long P Le, A John Iafrate, Martha B Pitman
• Journal: Cancer cytopathology (Cancer Cytopathol) Vol. 125 Issue 1 Pg. 41-47 (Jan 2017) ISSN: 1934-6638 [Electronic] United States
• PMID: 27647802 (Publication Type: Journal Article)
• Copyright: © 2016 American Cancer Society.

Chemical References

• Biomarkers, Tumor
• Carcinoembryonic Antigen
• Neoplasm Proteins

Topics

• Adolescent
• Adult
• Aged
• Aged, 80 and over
• Biomarkers, Tumor (genetics)
• Carcinoembryonic Antigen (genetics)
• Cyst Fluid (metabolism)
• Cystadenoma, Mucinous (diagnosis, genetics, surgery)
• Cytodiagnosis
• Female
• High-Throughput Nucleotide Sequencing
• Humans
• Male
• Middle Aged
• Mutation
• Neoplasm Proteins (genetics)
• Pancreatic Cyst (diagnosis, genetics, pathology)
• Preoperative Period