8-Methoxypsoralen (8-MOP), Serum
NY State Approved Indicates the status of NY State approval and if the test is orderable for NY State clients.
Monitoring adequacy of blood levels during extracorporeal photopheresis.
High-Performance Liquid Chromatography (HPLC)
Reporting Name A shorter/abbreviated version of the Published Name for a test; an abbreviated test name
8-Methoxypsoralen (8-MOP), S
Specimen Type Describes the specimen type needed for testing
Specimen Required Defines the optimal specimen. This field describes the type of specimen required to perform the test and the preferred volume to complete testing. The volume allows automated processing, fastest throughput and, when indicated, repeat or reflex testing.
Collection Container/Tube: Red top
Submission Container/Tube: Amber vial (Supply T192)
Specimen Volume: 3 mL
1. Draw blood 2 to 3 hours after patient has ingested 8-MOP.
2. Spin down within 2 hours of draw.
3. Send specimen in amber vial to protect from light.
Specimen Minimum Volume Defines the amount of specimen required to perform an assay once, including instrument and container dead space. Submitting the minimum specimen volume makes it impossible to repeat the test or perform confirmatory or perform reflex testing. In some situations, a minimum specimen volume may result in a QNS (quantity not sufficient) result, requiring a second specimen to be collected.
Mild OK; Gross reject
Mild OK; Gross reject
Mild OK; Gross reject
Serum gel tube
Specimen Stability Information Provides a description of the temperatures required to transport a specimen to the laboratory. Alternate acceptable temperature(s) are also included.
|Serum Red||Refrigerated (preferred)||14 days|
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
8-Methoxypsoralen (8-MOP) is a photosensitizing drug given to patients who are undergoing extracorporeal photopheresis (ECPP) for the palliative treatment of cutaneous T-cell lymphoma (Sezary syndrome and mycosis fungoides). 8-MOP is also used in the ultraviolet treatment (PUVA) of severe psoriasis.
The process of leukopheresis removes leukocytes from the blood so that therapeutic doses of long-wavelength ultraviolet light (UVA) can reach the 8-MOP-sensitized leukocytes; after exposure of the blood to UVA, the leukophoretic process is completed by returning the treated blood to the patient. 8-MOP and UVA act together to produce the desired beneficial effect on the patient, namely the reduction in the growth of specific lymphocyte subpopulations. ECPP stimulates an immune reaction that results in large numbers of damaged T-cells being eliminated from the circulation and the tissue reservoirs shortly after ECPP; patients appear to exhibit a vaccine-like response to the reinfused cells, with, in the best scenario, a lasting suppression of malignant T-cells.
For the UVA treatments to be effective, optimal levels of 8-MOP must be present in the patient's blood. Because 8-MOP exhibits a significant first pass hepatic effect, there is considerable intra-individual variation in 8-MOP blood levels. Because of these variations, 8-MOP blood levels should be measured on a periodic basis to ensure that optimal 8-MOP levels are present in patients undergoing ECPP and PUVA. Optimal response to therapy is achieved when the serum concentration of 8-MOP is in the range of 50 to 125 ng/mL.
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
Blood levels of 8-methoxypsoralen must be within the concentration range of 50 to 125 ng/mL during phototherapy in order for the drug to bind to T-cells in adequate concentration to ensure their destruction during photopheresis.
The clinical effect desired will not be achieved if the blood level is <50 ng/mL during phototherapy.
Levels >125 ng/mL provide no additional benefit and increase the likelihood of toxic effects.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
8-Methoxypsoralen is light-sensitive. Protect the specimen from direct exposure to intense light for prolonged periods of time. Wrap the specimen in foil to protect it during shipping.
Clinical Reference Provides recommendations for further in-depth reading of a clinical nature
Gasparro F: Use of psoralen during photopheresis. Photopheresis Review, Johnson and Johnson Company
Method Description Describes how the test is performed and provides a method-specific reference
8-Methoxypsoralen (8-MOP) is extracted into a solvent mixture from serum that has been alkalinized by the addition of a borate buffer. The solvent layer is transferred to a clean, conical-tip tube and dried with heat under air flow. The residue is reconstituted in mobile phase and an aliquot is analyzed by HPLC.(Edelson R, Berger C, Gasparro F, et al: Treatment of cutaneous T-cell lymphoma by extracorporeal photochemotherapy: preliminary results. N Engl J Med 1987;316:297-303)
Day(s) and Time(s) Test Performed Outlines the days and times the test is performed. This field reflects the day and time the sample must be in the testing laboratory to begin the testing process and includes any specimen preparation and processing time required before the test is performed. Some tests are listed as continuously performed, which means assays are performed several times during the day.
Tuesday; 11 a.m.
Analytic Time Defines the amount of time it takes the laboratory to setup and perform the test. This is defined in number of days. The shortest interval of time expressed is "same day/1 day," which means the results may be available the same day that the sample is received in the testing laboratory. One day means results are available 1 day after the sample is received in the laboratory.
Maximum Laboratory Time Defines the maximum time from specimen receipt at Mayo Medical Laboratories until the release of the test result
Specimen Retention Time Outlines the length of time after testing that a specimen is kept in the laboratory before it is discarded
Performing Laboratory Location The location of the laboratory that performs the test
Test Classification Provides information regarding the medical device classification for laboratory test kits and reagents. Tests may be classified as cleared or approved by the US Food and Drug Administration (FDA) and used per manufacturer's instructions, or as products that do not undergo full FDA review and approval, and are then labeled as an Analyte Specific Reagent (ASR), Investigation Use Only (IUO) product, or a Research Use Only (RUO) product.
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the U.S. Food and Drug Administration.
CPT Code Information Provides guidance in determining the appropriate Current Procedural Terminology (CPT) code(s) information for each test or profile. The listed CPT codes reflect Mayo Medical Laboratories interpretation of CPT coding requirements. It is the responsibility of each laboratory to determine correct CPT codes to use for billing.
LOINC® Code Information Provides guidance in determining the Logical Observation Identifiers Names and Codes (LOINC) values for the result codes returned for this test or profile.
|Result ID||Reporting Name||LOINC Code|
|80296||8-Methoxypsoralen (8-MOP), S||13625-9|