Rüdiger Heicappell

Methylation‐specific PCR for detection of neoplastic DNA in biopsy washings

Epigenetic DNA alterations such as promoter hypermethylation of glutathione S‐transferase P1 (GSTP1) in prostatic adenocarcinoma frequently constitute tumour biomarkers. Neoplastic transformation was identified in washings of prostate biopsies by GSTP1 promoter hypermethylation, using methylation‐specific PCR (MSP). Twenty‐six patients undergoing sextant transrectal prostate biopsies for clinically suspected prostate cancer were enrolled. All ten patients diagnosed with adenocarcinoma (100%) and four of six patients with prostatic intraepithelial neoplasia (67%), but none of ten patients with benign hyperplasia (0%), exhibited GSTP1 promoter hypermethylation in at least one out of six biopsy washings. Since this approach is transferable to various cancer entities, a sensitive and specific DNA‐based analysis of biopsy material seems generally feasible without impeding routine histopathological examination. Copyright

Molecular staging of surgical margins after radical prostatectomy by detection of telomerase activity

BACKGROUNDnThe further course of prostate cancer (PC) after radical prostatectomy (RPX) is decisively influenced by the local tumor stage. Although it is thus far possible to assess the risk of local recurrence from the pathohistology, precise predictions cannot be made. A more precise evaluation would be desirable, mainly for early planning of adjuvant therapy. Other authors have shown that telomerase activity may be a marker for malignant potential. We assessed the detection of telomerase activity using the telomeric repeat amplification protocol (TRAP) in surgical margins compared to conventional histopathological examination.nnnMETHODSnNinety-two patients with local PC who underwent RPX were examined. After RPX biopsies were obtained from four defined areas of the prostatic fossa and processed by TRAP assay for telomerase activity using a standard protocol.nnnRESULTSnIn 5 of 48 patients (10.4%) with organ-confined prostate carcinoma (pT2) telomerase activity could be detected. Seven of 47 patients (14.9%) with locally advanced PC (> pT2) had at least one positive specimen.nnnCONCLUSIONSnThe results obtained in our study indicate that detection of telomerase activity by TRAP assay may be a suitable parameter for molecular staging of surgical margins, because of the high tumor-specificity. Further follow-up must clarify whether patients with positive molecular detection have an increased risk of local recurrence.