The fine needle biopsy (FNA) of the tumor is taken up in a special nucleic acid stabilizing solution. RNA isolation (total RNA) is then performed following standard protocols and RNA is converted to complementary DNA (cDNA). Finally, the gene expression for several genes is determined in order to create a molecular profile that will reveal the exact identity of the biopsy cells and will contribute to its proper management.

The real-time PCR method is used to determine the expression of many cellular receptors as well as common activating mutations in these receptors, mitotic genes, tumor suppressor and antiapoptotic genes compared to non-transferable reference genes. in pathological conditions (housekeeping control genes) according to published protocols.