The added value of molecular testing in small pancreatic cysts.
BACKGROUND
Recent studies have shown high amplitude K-ras gene mutation and allelic imbalances are predictive of malignancy in pancreatic cysts.


OBJECTIVE
Our purpose is to determine the added benefit of molecular testing in diagnosing small pancreatic cysts.


METHODS
Retrospective, single-institution study.


METHODS
Patients with pancreatic cysts (less than, or equal to, 3 cm) who presented for EUS evaluation.


METHODS
EUS-guided pancreatic cyst aspiration cytology, carcinoembryonic antigen (CEA) level determination, and detailed DNA analysis including K-ras gene mutation and allelic imbalance.


METHODS
Ability of cyst fluid DNA analysis to render a diagnosis compared with cytology and CEA level determination.


RESULTS
Diagnostic agreement was seen in 55.6% (35/63) of cases. In 10 cases (15.9%), there was disagreement between cytology and molecular. Molecular testing provided a diagnosis in 20 cases (31.7%) when either cytology was unsatisfactory, or CEA not elevated (less than 192 ng/mL). Elevated CEA levels were seen in 16 cases (25.4%), each diagnosed as a mucinous lesion with molecular analysis.


CONCLUSIONS
Molecular analysis of pancreatic cyst fluid adds diagnostic value in scant specimens when cytology may be unsatisfactory and CEA unreliable.
Department of Pathology, Anatomy, and Cell Biology, Thomas Jefferson University Hospital, Philadelphia, PA 19107, USA. adam.toll@jeffersonhospital.org
Adam D
AD
Toll
Thomas
T
Kowalski
David
D
Loren
Marluce
M
Bibbo
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000032:analysis / Q000235:genetics; D044963:Biopsy, Fine-Needle; D002272:Carcinoembryonic Antigen / Q000032:analysis / Q000235:genetics; D020420:Cyst Fluid / Q000737:chemistry; D019160:Endosonography; D005260:Female; D011905:Genes, ras / Q000235:genetics; D006801:Humans; D008297:Male; D008875:Middle Aged; D025202:Molecular Diagnostic Techniques / Q000379:methods*; D010181:Pancreatic Cyst / Q000175:diagnosis* / Q000473:pathology; D011237:Predictive Value of Tests; D012189:Retrospective Studies; D047368:Tumor Burden; D055815:Young Adult
D014408:Biomarkers, Tumor; D002272:Carcinoembryonic Antigen