Minimum altered regions in early prostate cancer progression identified by high resolution whole genome tiling path BAC array comparative hybridization.

BACKGROUND: Carcinoma of the prostate (CaP) is a serious health problem. The altered molecular mechanisms that lead to this disease are poorly understood. METHODS: Specimens from radical prostatectomies and blood were collected from 18 CaP surgery patients. For CGH studies, 20 CaP-related samples (16 Gleason grade 3, 3 higher grades, 1 BPH sample) and 18 samples of patient-matched normal epithelial cells were obtained by laser-assisted microdissection from frozen sections of the 18 prostatectomy specimens. High resolution SMRT aCGH was used to compare genomic profiles of prostatic samples to patient-matched blood and pooled female DNA. TMPRSS2-ERG fusion transcript analysis was performed by RT-PCR in relation to alterations detected at the TMPRSS2 locus. RESULTS: Our comprehensive aCGH approach allowed us to define 35 regions of recurrent alterations while excluding germline copy number polymorphisms. Novel regions identified include 2q14.2, containing INHBB, and 17q21.31. The TMPRSS2 locus at 21q22.3 may be a hotspot for rearrangements with 75% of the alterations resulting in the expression of a TMPRSS2-ERG fusion transcript. Differences in fusion expression in different areas in an individual tumor focus and expression in adjacent normal epithelium supported intrafocal heterogeneity and field cancerization, respectively. Both features challenge our efforts to develop more objective markers for diagnosis and prediction of the severity of CaP. CONCLUSION: The high-density array enabled precise mapping of genomic alterations and consequently definition of minimum altered regions smaller than previously reported thus facilitating identification of those genes that contribute to the cancer transformation process.

Clinical impact of second pathology opinion: a longitudinal study of central genitourinary pathology review before prostate brachytherapy.

PURPOSE: To evaluate the clinical impact of pathology review before prostate brachytherapy. METHODS AND MATERIALS: Original and reviewing pathologists' reports were retrospectively collected from 1323 men treated with prostate brachytherapy between July 1998 and October 2005 at one institution. Statistical analysis was performed pre- and post-January 2002. The clinical impact of pathology review was evaluated. RESULTS: Gleason Score (GS) change (GS(Delta)) occurred in 25.2% (334) of cases; GS increased in 21.6%, decreased in 2.4%, and diagnosed malignancy in 1.2% of cases. Post-2002, concordance in attributed GS improved, with GS(Delta) of 31.9-20.6%, respectively (p<0.001), and a reduction in the average GS(Delta) (p<0.001). The clinical impact was substantial with management changing in 14.8% of cases. CONCLUSION: Concordance between the original and reviewing pathologists' GS has improved during the study period. Nevertheless, discordance persists in one of five cases. Pathology review remains essential, if treatment decisions hinge on GS.

Protein profiling of microdissected prostate tissue links growth differentiation factor 15 to prostate carcinogenesis.

Identification of proteomic alterations associated with early stages in the development of prostate cancer may facilitate understanding of progression of this highly variable disease. Matched normal, high-grade prostatic intraepithelial neoplasia (hPIN) and prostate cancer cells of predominantly Gleason grade 3 were procured by laser capture microdissection from serial sections obtained from snap-frozen samples dissected from 22 radical prostatectomy specimens. From these cells, protein profiles were generated by surface-enhanced laser desorption/ionization-time of flight mass spectrometry. A 24-kDa peak was observed at low or high intensity in profiles of prostate cancer cells in 19 of 27 lesions and at low intensity in 3 of 8 hPIN lesions but was not detectable in matched normal cells. SDS-PAGE analysis of prostate cancer and matched normal epithelium confirmed expression of a prostate cancer-specific 24-kDa protein. Mass spectrometry and protein data-based analysis identified the protein as the dimeric form of mature growth differentiation factor 15 (GDF15). The increased expression of mature GDF15 protein in prostate cancer cells cannot be explained on the basis of up-regulation of GDF15 mRNA because reverse transcription-PCR analysis showed similar amounts of transcript in normal, hPIN, and prostate cancer cells that were obtained by laser capture microdissection in the same set of serial sections from which the protein profiles were obtained. Our findings suggest that early prostate carcinogenesis is associated with expression of mature GDF15 protein.

Encapsulated apocrine papillary carcinoma of the breast--a tumour of uncertain malignant potential: report of five cases.

Five cases of an unusual encapsulated apocrine papillary tumour are reported. All presented as cystic masses in the breast of women aged 44-84 years. Imaging studies showed a complex cyst often with one or more mural nodules. The key histological features are similar to those of classical encapsulated papillary carcinoma in that myoepithelial cells were absent within the papillary structures and at the periphery of the cyst. All were pure apocrine in type and showed variable degrees of cytological atypia and mitotic activity. All lacked evidence of malignancy in the breast tissue outside of the lesion. Sentinel lymph node biopsies performed in three of the cases were negative for metastases, and all have behaved in a benign fashion.