As an adjunct in the assessment of pancreatic cysts, when used in conjunction with carcinoembryonic antigen, amylase, imaging studies and cytology
Immunoenzymatic Assay
CA 19-9 (Carbohydrate Antigen 19-9)
Cancer Antigen 19-9 (CA 19-9)
Pancreatic Cyst Fluid
This test should not be ordered for pancreatic fluid of noncystic origin (eg, pancreatic duct fluid, peripancreatic fluid) since reference values have not been established for those specimen types. For ordering assistance call 800-533-1710.
Question ID | Description | Answers |
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SITE6 | Site |
Patient Preparation: For 12 hours before this procedure do not take multivitamins or dietary supplements containing biotin (vitamin B7), which is commonly found in hair, skin, and nail supplements and multivitamins.
Container/Tube: Plain, plastic, screw-top tube
Specimen Volume: 1 mL
If not ordering electronically, complete, print, and send an Oncology Test Request (T729) with the specimen.
0.5 mL
Gross hemolysis | Reject |
Gross icterus | OK |
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Pancreatic Cyst Fluid | Frozen (preferred) | 90 days | |
Refrigerated | 7 days | ||
Ambient | 72 hours |
As an adjunct in the assessment of pancreatic cysts, when used in conjunction with carcinoembryonic antigen, amylase, imaging studies and cytology
Carbohydrate antigen 19-9 (CA 19-9) is a modified Lewis(a) blood group antigen that has been used as a tumor marker. Serum CA 19-9 concentrations may be elevated in patients with gastrointestinal malignancies, such as cholangiocarcinoma, colon cancer, or pancreatic cancer. While serum CA 19-9 is neither sensitive nor specific for pancreatic cancer, concentrations of CA 19-9 in pancreatic cyst fluid may help determine whether a pancreatic cyst is benign.
Cystic lesions of the pancreas are of various types:
Benign cysts:
-Inflammatory cysts (pseudocysts)
-Serous cysts (serous cystadenoma)
Mucinous cysts:
-Premalignant (mucinous cystadenoma)
-Malignant (cystadenocarcinoma, intrapapillary mucinous neoplasia)
Pancreatic cyst fluid CA 19-9 results should be used in conjunction with imaging studies, cytology, and other cyst-fluid tumor markers, such as carcinoembryonic antigen and amylase.
An interpretive report will be provided.
Cyst fluid carbohydrate antigen 19-9 (CA19-9) concentrations less than 37 U/mL indicate a low risk for a mucinous cyst and are more consistent with serous cystadenoma or pseudocyst. The sensitivity and specificity are approximately 19% and 98%, respectively, at this concentration.
Correlation of these test results with cytology and imaging is recommended.
Carbohydrate antigen 19-9 (CA 19-9) and other tumor markers are not specific for malignancy, and CA 19-9 testing has limited utility when used as the sole tumor marker test. Other tests (eg, carcinoembryonic antigen, amylase, cytology) should be performed in conjunction with CA 19-9 for assessing pancreatic cyst aspirates.
A low or negative result (<5 U/mL) may be uninformative or misleading since some individuals (Lewis nonsecretors) do not produce the CA 19-9 antigen. In such cases, a serum CA 19-9 measurement is necessary to verify that the patient is (or is not) a CA 19-9 secretor.
In rare cases, some individuals can develop antibodies to mouse or other animal antibodies (often referred to as human anti-mouse antibodies [HAMA] or heterophile antibodies), which may cause interference in some immunoassays. Caution should be used in interpretation of results, and the laboratory should be alerted if the result does not correlate with the clinical presentation.
1. Snozek CL, Jenkins SM, Bryant SC, et al: . Analysis of CEA, CA19-9 and amylase in pancreatic cyst fluid for diagnosis of pancreatic lesions. Clin Chem. 2008;54(6 Suppl S):A126-127
2. van der Waaij LA, van Dullemen HM, Porte RJ. Cyst fluid analysis in the differential diagnosis of pancreatic cystic lesions: a polled analysis. Gastrointest Endosc. 2005;62(3):383-389
3. Khalid A, Brugge W. ACG practice guidelines for the diagnosis and management of neoplastic pancreatic cysts. Am J Gastroenterol. 2007;102(10):2339-2349
4. Elta GH, Enestvedt BK, Sauer BG, Lennon AM. ACG clinical guideline: diagnosis and management of pancreatic cysts. Am J Gastroenterol. 2018;113(4):464-479. doi:10.1038/ajg.2018.14
The Access GI Monitor assay is a 2-site immunoenzymatic sandwich assay. A sample is added to a reaction vessel along with paramagnetic particles coated with polyclonal goat antibiotin antibody, mouse monoclonal biotin conjugate, and buffered protein solution. After incubation in a reaction vessel, separation in a magnetic field, and washing to remove materials not bound to the solid phase, a monoclonal-alkaline phosphatase conjugate is added. After incubation in a reaction vessel, materials bound to the solid phase are held in a magnetic field, while unbound materials are washed away. The chemiluminescent substrate Lumi-Phos 530 is added to the vessel and light generated by the reaction is measured with a luminometer. The light production is directly proportional to the concentration of CA 19-9 antigen in the sample. The amount of analyte in the sample is determined from a stored, multipoint calibration curve.(Package insert: Access GI Monitor. Beckman Coulter, Inc.; 04/2019)
Monday through Friday
This test has been modified from the manufacturer's instructions. Its performance characteristics were determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.
86301
Test Id | Test Order Name | Order LOINC Value |
---|---|---|
199PC | CA19-9, Pancreatic Cyst | 97750-4 |
Result Id | Test Result Name |
Result LOINC Value
Applies only to results expressed in units of measure originally reported by the performing laboratory. These values do not apply to results that are converted to other units of measure.
|
---|---|---|
199P | CA19-9, Pancreatic Cyst | 97750-4 |
SITE6 | Site | 39111-0 |