CHROMOSOMES 1p / 19q FISH ANALYSIS- UF Path Labs
Chromosome 1p: DELETED Chromosome 19q: DELETEDINTERPRETATIONThere is co-deletion of chromosomes 1p or 19q deletion in the tissue analyzed. CLINICAL STUDIES HAVE SUGGESTED THAT COMBINED LOSS OF CHROMOSOME 1P AND 19Q IN OLIGODENDROGLIAL BRAIN TUMORS MAY BE ASSOCIATED WITH PROLONGED SURVIVAL AND ENHANCED RESPONSE TO CHEMOTHERAPY (REFS 1-5).
Chromosome 1p: NON-DELETED Chromosome 19q: NON-DELETEDINTERPRETATIONThere is no evidence of a chromosome 1p or 19q deletion in the tissue analyzed. CLINICAL STUDIES HAVE SUGGESTED THAT COMBINED LOSS OF CHROMOSOME 1P AND 19Q IN OLIGODENDROGLIAL BRAIN TUMORS MAY BE ASSOCIATED WITH PROLONGED SURVIVAL AND ENHANCED RESPONSE TO CHEMOTHERAPY (REFS 1-5).
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Case Number: USS/RSS - Block
Anatomic site: Brain tumor, location, procedure
Reference range: 1p/ 19q: Non-deleted
A tumor is considered to have 1p or 19q deletion when the 1p probe to 1q probe ratio (1p/1q) or the 19q probe to 19p probe ratio (19q/19p) is <0.80. A tumor is considered to have 19q gain when the 19q/19p ratio is >1.30. A tumor is considered to have chromosome 1 or 19 gain when the percentage of nuclei with > or =3 signals is >20%. A normal 1p/1q ratio is 0.9-1.05 and a normal 19q/19 p ratio is 0.93-1.02.
The test uses two dual-probe Vysis FISH 1p36 probe combined with a control 1q probe and a 19q13.3 probe combined with a control 19p probe. Probes are specific to the minimally deleted regions of 1p (1p36) and 19q (19q13.3) to detect 1p and 19q deletion. The selection of tissue and the identification of target areas on the H&E stained slide is performed by a pathologist. The number of 1p and 19q signals in the area of interest is scored. The testing was performed and performance characteristics of this test were validated by the University of Florida Pathology Laboratories- 4800 SW 35th St, Gainesville, FL 32608. It has not been cleared or approved by the FDA. This test is used for clinical purposes. It should not be regarded as investigational or for research. This laboratory is certified under the Clinical Laboratory Improvement Amendments to perform high complexity clinical laboratory testing.