Circulating prostate-specific antigen mRNA during radical prostatectomy inpatients with localized prostate cancer: with special reference to neoadjuvant hormonal therapy

To determine the potential risk of hematogenous dissemination of prostate c ancer cells during radical prostatectomy (RP), we investigated the pre- and intraoperative circulating prostate-specific antigen (PSA) mRNA in patient s with clinically localized prostate cancer, with special reference to neoa djuvant hormonal therapy (NHT). Using a nested reverse transcriptase (RT) p olymerase reaction (PCR) assay, PSA mRNA in the peripheral blood was evalua ted pre- and postoperatively in a total of 23 patients, 10 of whom received NHT with antiandrogens. The RT-PCR assay employed detected one LNCaP cell in 10(7) mononuclear blood cells, and showed no positive signal in the bloo d samples from all 15 healthy controls. Pre- and intraoperative circulating PSA mRNA was positive in 11 (48%) and 18 patients (78%), respectively. All 11 patients with positive preoperative PSA mRNA continued to be positive d uring RP, and seven (58%) of 12 patients with negative preoperative PSA mRN A had a positive conversion. Although the patients' ages, preoperative seru m PSA values and clinical or pathological stages were not associated with t he pre- and intraoperative PSA mRNA results, the NHT group showed a signifi cantly lower incidence of preoperative PSA mRNA positivity (2/10) than the group receiving RP alone (9/13) (20% vs 69%, P = 0.036). NHT, however, show ed no suppressive effect on either intraoperative positivity or positive co nversion of circulating PSA mRNA. The present study suggests that a substan tial number of patients receiving RP are at risk of hematogenous disseminat ion, and NHT with antiandrogens has a minimal or no suppressive effect on t he circulating PSA mRNA during surgical manipulation of the prostate. Becau se the clinical significance of circulating cancer cells remains to be dete rmined, long-term follow-up in association with the circulating cancer cell s assessed by the RT-PCR is essential in order to establish the role of mol ecular staging as well as NHT.