Keratin mRNA for detecting micrometastasis in cervical lymph nodes of oralcancer

We studied three keratin (K) gene candidates, K13, K19, and K20 mRNAs, for detecting micrometastases in cervical lymph nodes (LNs) by reverse transcri ptase-polymerase chain reaction (RT-PCR). Of 166 histologically metastasis- negative nodes, 24 micrometastatic LNs (14.4%) were detected based on K13 g ene expression. Keratin 19 mRNA is an inadequate marker for the genetic dia gnosis due to not only illegitimate gene expression from lymphatic tissue b ut also gene expression from the ectopic salivary gland. Keratin 20 mRNA sh owed low sensitivity. It is suggested that K13 mRNA may be a promising tumo r marker among these keratin genes for detecting the micrometastases in cer vical LNs of oral cancer. (C) 2000 Elsevier Science Ireland Ltd. All rights reserved.