RESUMO
AIM: To evaluate the utility of a multigene real-time reverse transcriptase polymerase chain reaction (RT-PCR) assay to detect circulating tumor cells in peripheral blood specimens of breast cancer patients during or after treatment. METHOD: Using this assay, peripheral blood samples were analyzed for expression levels of mammaglobin and three complementary transcribed breast cancer-specific genes: B305D, gamma-aminobutyrate type A receptor pi subunit (GABA pi; GABRP), and B726P. We examined 172 blood specimens from 82 breast cancer patients during or after therapy for the presence of circulating tumor cells using the multigene real-time RT-PCR assay. RESULTS: In 63.4% of the blood samples, a positive signal for mammaglobin and/or three breast cancer-associated gene transcripts was detected. Of breast cancer patients, 75.6% had at least one positive blood sample. Blood specimens from 51 of 53 healthy female volunteers tested negative in the assay whereas two samples had a low expression signal. In addition, three patients were monitored for more than a year during their adjuvant therapy treatment. CONCLUSION: This assay could be a valuable tool for monitoring breast cancer patients during and after therapy.
