Quantitative GSTP1 methylation and the detection of prostate adenocarcinoma in sextant biopsies.
Hypermethylation of the 5' promoter region of the glutathione S-transferase pi gene (GSTP1) occurs at a very high frequency in prostate adenocarcinoma. We compared the results of blinded histologic review of sextant biopsy samples from 72 excised prostates with those obtained using a quantitative methylation-specific polymerase chain reaction assay (QMSP) for GSTP1. Formal surgical pathologic review of the resected prostates was used to determine the number of patients with (n = 61) and without (n = 11) prostate cancer. Histology alone detected prostate carcinoma with 64% sensitivity (95% confidence interval [CI] = 51% to 76%) and 100% specificity (95% CI = 72% to 100%), whereas the combination of histology and GSTP1 QMSP at an assay threshold greater than 10 detected prostate carcinoma with 75% sensitivity (95% CI = 63% to 86%) and 100% specificity (95% CI = 72% to 100%), an 11% improvement (95% CI = 5% to 22%) in sensitivity over histology alone. The combination of histology and GSTP1 QMSP at an assay threshold greater than 5 detected prostate adenocarcinoma with 79% sensitivity (95% CI = 68% to 89%), a 15% improvement (95% CI = 7% to 26%) over histology alone. Thus, GSTP1 QMSP improved the sensitivity of histologic review of random needle biopsies for prostate cancer diagnosis. Further studies should determine whether detection of GSTP1 hypermethylation in a biopsy sample with normal histology indicates the need for an early repeat biopsy at the same site.
Harden
Susan V
SV
Department of Otolaryngology-Head and Neck Surgery, The Johns Hopkins University School of Medicine, Baltimore, MD 21205-2196, USA.
Sanderson
Harriette
H
Goodman
Steven N
SN
Partin
Alan A W
AA
Walsh
Patrick C
PC
Epstein
Jonathan I
JI
Sidransky
David
D
D000230:Adenocarcinoma / Q000175:diagnosis* / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D014408:Biomarkers, Tumor / Q000378:metabolism*; D001707:Biopsy, Needle; D004273:DNA, Neoplasm / Q000378:metabolism; D051549:Glutathione S-Transferase pi; D005982:Glutathione Transferase / Q000378:metabolism*; D006801:Humans; D007527:Isoenzymes / Q000378:metabolism*; D008297:Male; D008745:Methylation; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D011471:Prostatic Neoplasms / Q000175:diagnosis* / Q000378:metabolism* / Q000473:pathology / Q000601:surgery; D012680:Sensitivity and Specificity
D014408:Biomarkers, Tumor; D004273:DNA, Neoplasm; D007527:Isoenzymes; C496556:GSTP1 protein, human; D051549:Glutathione S-Transferase pi; D005982:Glutathione Transferase