David K. Ornstein

A PROSPECTIVE RANDOMIZED TRIAL COMPARING 6 VERSUS 12 PROSTATE BIOPSY CORES: IMPACT ON CANCER DETECTION

PURPOSE Several studies suggest that sextant transrectal ultrasound guided biopsy of the prostate provides insufficient material to detect all clinically important prostate cancer, and obtaining more biopsy cores may improve the cancer detection rate. We performed a prospective randomized trial comparing 6 to 12 prostate biopsy cores to determine the impact on the cancer detection rate. MATERIALS AND METHODS We prospectively randomized 244 men, including 71 (29%) black men, with a mean age plus or minus standard deviation of 65 +/- 8 years to undergo biopsy with 6 or 12 peripheral zone tissue cores. In our study subjects serum total prostate specific antigen (PSA) was between 2.5 and 20 ng./ml., and/or digital rectal examination was suspicious for cancer. All men completed a self-administered pre-biopsy and 2 post-biopsy questionnaires at 2 and 4 weeks. Cancer detection rates were compared in the groups and correlated with race, biopsy history, digital rectal examination findings, total PSA, transrectal ultrasound volume and PSA density, as determined by the formula, total PSA/transrectal ultrasound volume. RESULTS The cancer detection rate in the 6 and 12 core groups was almost identical (26% and 27%, p = 0.9). There was no significant difference in cancer detection in the 2 trial arms with respect to subject race, biopsy history, digital rectal examination findings, total PSA, transrectal ultrasound volume or PSA density. However, our study did not have the statistical power to rule out small differences. CONCLUSIONS The overall cancer detection rate is not materially increased by 12 core, peripheral zone biopsy in men in whom prostate cancer was mainly detected by screening.

Proteomic analysis of laser capture microdissected human prostate cancer and in vitro prostate cell lines

Specific populations of normal and malignant epithelium from three radical prostatectomy tissue specimes were procured by laser capture microdissection (LCM) and analyzed by two‐dimensional polyacrylamide gel electrophoresis (2‐D PAGE). Six proteins that were only seen in malignant cells and two proteins that were only seen in benign epithelium were reproducibly observed in two of two cases examined. Furthermore, these proteins were not observed in the 2‐D PAGE profiles from the patient‐matched microdissected stromal cell populations, but were seen in the protein profiles from the undissected whole cryostat sections. One of these proteins was determined to be prostate‐specific antigen (PSA) by Western blot analysis, and intriguingly the remaining protein candidates were found to be at least as abundant as the PSA protein. Comparison of 2‐D PAGE profiles of microdissected cell with matched in vitro cell lines from the same patient, and metastatic prostate cancer cell lines (LnCaP and PC3) showed striking differences between prostate cells in vivo and in vitro with less than 20% shared proteins. The data demonstrate that 2‐D PAGE analysis of LCM‐derived cells can reliably detect alterations in protein expression associated with prostate cancer, and that these differentially expressed proteins are produced in high enough levels which could allow for their clinical utility as new targets for therapeutic intervention, serum markers, and/or imaging markers.

An approach to proteomic analysis of human tumors.

A strategy for proteomic analysis of microdissected cells derived from human tumor specimens is described and demonstrated by using esophageal cancer as an example. Normal squamous epithelium and corresponding tumor cells from two patients were procured by laser‐capture microdissection and studied by two‐dimensional polyacrylamide gel electrophoresis (2D‐PAGE). Fifty thousand cells resolved approximately 675 distinct proteins (or isoforms) with molecular weights ranging between 10 and 200 kDa and isoelectric points of pH 3–10. Comparison of the microdissected protein profiles showed a high degree of similarity between the matched normal‐tumor samples (98% identical). However, 17 proteins showed tumor‐specific alterations, including 10 that were uniquely present in the tumors and seven that were observed only in the normal epithelium. Two of the altered proteins were characterized by mass spectrometry and immunoblot analysis and were identified as cytokeratin 1 and annexin I. Acquisition of 2D‐PAGE protein profiles, visualization of disregulated proteins, and subsequent determination of the identity of selected proteins through high‐sensitivity MS‐MS microsequencing are possible from microdissected cell populations. These separation and analytical techniques are uniquely capable of detecting tumor‐specific alterations. Continued refinement of techniques and methodologies to determine the abundance and status of proteins in vivo holds great promise for future study of normal cells and associated neoplasms. Mol. Carcinog. 27:158–165, 2000. Published by Wiley‐Liss Inc.

PAIN AND MORBIDITY OF TRANSRECTAL ULTRASOUND GUIDED PROSTATE BIOPSY: A PROSPECTIVE RANDOMIZED TRIAL OF 6 VERSUS 12 CORES

PURPOSE An increasing number of studies suggest that 6-sector transrectal ultrasound guided biopsy of the prostate provides insufficient material to detect all clinically important prostate cancers and more cores may improve detection rates. We performed a prospective, randomized study to determine the effect of increasing the number of cores from 6 to 12 on pain and other morbidity associated with the biopsy procedure. MATERIALS AND METHODS A total of 160 men (44 black, 28%) with a mean age plus or minus standard deviation of 65+/-8 years who had serum prostate specific antigen between 2.5 and 20.0 ng./ml. and/or digital rectal examination findings suspicious for cancer were prospectively randomized to undergo 6 or 12-core biopsy. Patients completed a self-administered questionnaire addressing pain and other morbidity before, and immediately and 2 and 4 weeks after biopsy. RESULTS There was no difference between groups in mean pain scale with time for abdominal and rectal pain. For probe insertion, needle insertion and overall pain there was a significant increase in pain recalled at 2 which persisted at 4 weeks compared to immediately after biopsy. However, there was no difference for these 3 post-biopsy pain measures between the 6 and 12-core groups. In the 12-core group there was a statistically significant increase in hematochezia and hematospermia (24% versus 10%, p = 0.04 and 89% versus 71%, p = 0.01, respectively) but no significant difference between groups reporting morbidity as a moderate or major problem. There was no significant change in International Prostate Symptom Score, fever or hospitalization in the 12-core group. CONCLUSIONS The 12-core prostate biopsy procedure is generally well tolerated and can be safely performed with no significant difference in pain or morbidity compared to the 6-core procedure.

Rapid protein display profiling of cancer progression directly from human tissue using a protein biochip

The complicated, changing pattern of protein expression should contain important information about the pathologic process taking place in the cells of actual tissue. Utilization of this information for the selection of druggable targets could be possible if a means existed to rapidly analyze and display changes in protein expression in defined microscopic cellular subpopulations. As a demonstration of feasibility, we show the generation of sensitive, rapid, and reproducible molecular weight protein profiles of patient‐matched normal, premalignant, malignant, and metastatic microdissected cell populations from stained human esophageal, prostate, breast, ovary, colon, and hepatic tissue sections through the application of an affinity‐based biochip. Reproducible, discriminatory protein biomarker profiles can be obtained from as few as 25 cells in less than 5 min from dissection to the generation of the protein fingerprint. Furthermore, these protein pattern profiles reveal reproducible changes in expression as cells undergo malignant transformation, and are discriminatory for different tumor types. Consistent protein changes were identified in the microdissected cells from patient‐matched tumor and normal epithelium from eight out of eight different malignant esophageal tissue sets and three out of three malignant prostate tissue sets. A means to rapidly generate a display of expressed proteins from microscopic cellular populations sampled from tissue could be an important enabling technology for pharmacoproteomics, molecular pathology, drug intervention strategies, therapeutic assessment of drug entities, disease diagnosis, toxicity, and gene therapy monitoring. Drug Dev. Res. 49:34–42, 2000. Published 2000 Wiley‐Liss, Inc.

Robotic versus standard laparoscopic partial/wedge nephrectomy: a comparison of intraoperative and perioperative results from a single institution.

PURPOSE Laparoscopic partial/wedge nephrectomy, similar to laparoscopic radical prostatectomy, is a technically challenging procedure that is performed by a limited number of expert laparoscopic surgeons. The incorporation of a robotic surgical interface has dramatically increased the use of minimally invasive pelvic surgery such that robotic laparoscopic radical prostatectomy is commonly performed even by laparoscopically naïve surgeons. This analysis compares the outcomes of our initial experience with robot-assisted laparoscopic partial nephrectomy (RLPN) performed by an experienced open surgeon to that of standard laparoscopic partial nephrectomy (LPN) performed by two experienced laparoscopic surgeons. PATIENTS AND METHODS We reviewed the medical records of 11 consecutive patients who underwent 12 standard LPNs (EMM, RVC) (one patient had two unilateral tumors) and 10 consecutive patients (representing the first 11 of such robotic procedures performed at our institution) who underwent 11 RLPNs (one patient had bilateral tumors managed in an asynchronous manner) (DKO). RESULTS The mean tumor size was 2.3 cm (range 1.7-6.2 cm) for LPN and 3.1 cm (range 2.5-4 cm) for RLPN. The mean total procedure time was 289.5 minutes (range 145-369 min) for LPN and 228.7 minutes (range 98-375 min) for RLPN (P=0.102). The mean estimated blood loss was 198 mL (range 75-500 mL) for LPN v 115 mL (25-300 mL) for RLPN (P=0.169). The mean warm ischemia time was 35.3 minutes (range 15-49 min) in the LPN group and 32.1 minutes (range 30-45 minutes) in the RLPN group (P=0.501). CONCLUSIONS Introducing a robotic interface for laparoscopic partial/wedge resection allowed a fellowship-trained urologic oncologist with limited reconstructive laparoscopic experience to achieve results comparable to those for laparoscopic partial/wedge resection performed by experienced laparoscopic surgeons. In this regard, the learning curve appears truncated, similar to that with robot-assisted laparoscopic prostatectomy.

The Learning Curve of Robot-Assisted Radical Cystectomy: Results from the International Robotic Cystectomy Consortium

BACKGROUND Robot-assisted radical cystectomy (RARC) has evolved as a minimally invasive alternative to open radical cystectomy for patients with invasive bladder cancer. OBJECTIVE We sought to define the learning curve for RARC by evaluating results from a multicenter, contemporary, consecutive series of patients who underwent this procedure. DESIGN, SETTING, AND PARTICIPANTS Utilizing the International Robotic Cystectomy Consortium database, a prospectively maintained and institutional review board-approved database, we identified 496 patients who underwent RARC by 21 surgeons at 14 institutions from 2003 to 2009. MEASUREMENTS Cut-off points for operative time, lymph node yield (LNY), estimated blood loss (EBL), and margin positivity were identified. Using specifically designed statistical mixed models, we were able to inversely predict the number of patients required for an institution to reach the predetermined cut-off points. RESULTS AND LIMITATIONS Mean operative time was 386 min, mean EBL was 408 ml, and mean LNY was 18. Overall, 34 of 482 patients (7%) had a positive surgical margin (PSM). Using statistical models, it was estimated that 21 patients were required for operative time to reach 6.5h and 8, 20, and 30 patients were required to reach an LNY of 12, 16, and 20, respectively. For all patients, PSM rates of <5% were achieved after 30 patients. For patients with pathologic stage higher than T2, PSM rates of <15% were achieved after 24 patients. CONCLUSIONS RARC is a challenging procedure but is a technique that is reproducible throughout multiple centers. This report helps to define the learning curve for RARC and demonstrates an acceptable level of proficiency by the 30th case for proxy measures of RARC quality.

Proteomic analysis of human prostate cancer

Proteomics is a promising approach in the identification of proteins and biochemical pathways involved in tumorigenesis. In an effort to discover such proteins and pathways that are deregulated in prostate tumorigenesis, cellular proteomes of matched normal prostate epithelial cells and high‐grade prostate cancer cells were analyzed by tissue microdissection, two‐dimensional electrophoresis, and mass spectrometry. Forty protein alterations were detected in the tumors; however, the majority of these changes were not shared among the 12 neoplasms. In contrast, parallel cDNA microarray analysis identified a number of common gene expression changes. The marked heterogeneity of the observed protein alterations may have significance with regard to tumor biology and research strategies for molecular profiling analyses of human prostate cancer. Published 2002 Wiley‐Liss, Inc.

Surgical Margin Status After Robot Assisted Radical Cystectomy: Results From the International Robotic Cystectomy Consortium

PURPOSE Positive surgical margins at radical cystectomy confer a poor prognosis. We evaluated the incidence and predictors of positive surgical margins in patients who underwent robot assisted radical cystectomy for bladder cancer. MATERIALS AND METHODS Using the International Robotic Cystectomy Consortium database we identified 513 patients who underwent robot assisted radical cystectomy, as done by a total of 22 surgeons at 15 institutions from 2003 to 2009. After stratification by age group, gender, pathological T stage, nodal status, sequential case number and institutional volume logistic regression was used to correlate variables with the likelihood of a positive surgical margin. RESULTS Of the 513 patients 35 (6.8%) had a positive surgical margin. Increasing 10-year age group, lymph node positivity and higher pathological T stage were significantly associated with an increased likelihood of a positive margin (p = 0.010, <0.001 and p <0.001, respectively). Gender, sequential case number and institutional volume were not significantly associated with margin positivity. The rate of margin positive disease at cystectomy was 1.5% for pT2 or less, 8.8% for pT3 and 39% for pT4 disease. CONCLUSIONS Positive surgical margin rates at robot assisted radical cystectomy for advanced bladder cancer were similar to those in open cystectomy series in a large, multi-institutional, prospective cohort. Sequential case number, a surrogate for the learning curve and institutional volume were not significantly associated with positive margins at robot assisted radical cystectomy.

Molecular profiling of clinical tissue specimens: feasibility and applications.

The relationship between gene expression profiles and cellular behavior in humans is largely unknown. Expression patterns of individual cell types have yet to be precisely measured, and, at present, we know or can predict the function of a relatively small percentage of genes. However, biomedical research is in the midst of an informational and technological revolution with the potential to increase dramatically our understanding of how expression modulates cellular phenotype and response to the environment. The entire sequence of the human genome will be known by the year 2003 or earlier. 1,2 In concert, the pace of efforts to complete identification and full-length cDNA sequencing of all genes has accelerated, and these goals will be attained within the next few years. 3-7 Accompanying the expanding base of genetic information are several new technologies capable of global gene expression measurements. 8-16 Taken together, the expanding genetic database and developing expression technologies are leading to an exciting new paradigm in biomedical research known as molecular profiling.