MULTI-GENE VARIATION PANELS

Oncology Pharmacogenetics Gene Variation Panel

Synonyms: Oncology PGx panel

Test Overview

Several studies have shown that genetic predisposition accounts for a larger role in cancer development, progression, and response to therapy. Years of extensive genetic research, of shown that certain genes are now shown to be associated with a wide variety of cancers. Furthermore, the presence of specific genetic polymorphisms are responsible for poor or favored response or toxic effects of chemotherapy. Pharmacogenetic screening of such genes is often useful in predicting the individual patient response to chemotherapy, aids in the appropriate selection of a personalized medication regimen, and overall helps overcome the possibility of treatment failure. Considering the narrow therapeutic index of drugs for oncology and the need of elucidating the neoplasm, it is therefore vital to accurately select and administer the appropriate drug.

Multiple studies demonstrate specific drug-gene pairs that impact the delivery of oncology medication. For instance, tamoxifen and the gene CYP2D6 have a direct pharmacokinetic relationship, and individuals with this genotype favor a positive response to tamoxifen. These genes or gene variants are often termed ‘pharmacogenetic markers and testing of these markers all together via multiplex PCR, or next-generation sequencing enables significantly improved prediction of therapeutic response to prescribed medication. CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6, CYP3A4, CYP3A5, DPYD, MTHFR, NUDT15, TPMT, ABC, and ERCC are the commonly analyzed pharmacogenetic markers which are a part of the drug-gene pairs in oncology.

The following are some other drug-gene pairs and polymorphisms in these genes significantly alter the responses of subsequent drugs, either positively or negatively.

CYP2C19-Citalopram, Clopidogrel, Escitalopram.
CYP2D6- Codeine, Fluvoxamine, Fluoxetine, Tramadol, Tamoxifen, Paroxetine, Venlafaxine.
CYP3A5- Tacrolimus
TMPT- Triopurines
ERCC- Oxaliplatin
MTHFR- fluoropyrimidine

Clinical Utility:

  • Aids in the selection of appropriate drugs for oncology
  • Useful in predicting the response to the targeted therapy.
  • Helpful in determining recurrence, relapse, drug- toxicity, survival and mortality.