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Featured researches published by Michael O. Koch.


Urology | 2002

Transrectal high-intensity focused ultrasound for treatment of patients with stage T1b-2n0m0 localized prostate cancer: a preliminary report

Toyoaki Uchida; Narendra T. Sanghvi; Thomas A. Gardner; Michael O. Koch; Daisuke Ishii; Sadanori Minei; Takefumi Satoh; Toru Hyodo; Akira Irie; Shiro Baba

OBJECTIVES To present our preliminary clinical results of transrectal high-intensity focused ultrasound (HIFU) in Stage T1b-2N0M0 prostate cancer. Efforts are being made to provide minimally invasive alternative treatment options with equal efficacy and fewer side effects. HIFU delivers ultrasound energy with rapid thermal necrosis of tissue in the focal region without damaging the surrounding tissue. METHODS We performed 28 HIFU treatments in 20 patients with biopsy-proven localized prostate cancer using a modified Sonablate-200 HIFU device. All patient characteristics and the clinical outcome of 20 patients followed up more than 6 months (mean 13.5) were analyzed. RESULTS A complete response was obtained in 100% (20 of 20) of patients, as evidenced by a negative postoperative prostate biopsy and no elevation on three successive prostate-specific antigen (PSA) determinations. Of the 20 patients, 13 (65%), 5 (25%), and 2 (10%) had PSA nadirs of less than 0.50 ng/mL, 0.50 to 1.00 ng/mL, and 1.01 to 2.00 ng/mL, respectively. Rectourethral fistula and urethral stricture were noted in 1 and 2 patients, respectively, and 1 patient underwent transurethral resection of the prostate because of prolonged urinary retention. CONCLUSIONS Our results show that HIFU can be performed without an incision, with a less severe side effect profile, and, unlike most other prostate treatments, is repeatable. Transrectal HIFU may be a useful option for patients with localized prostate cancer. Its long-term efficacy will be determined by additional follow-up and a Phase II trial.


American Journal of Pathology | 2000

Enhanced Expression of Cyclooxygenase-2 in High Grade Human Transitional Cell Bladder Carcinomas

Martin Kömhoff; Youfei Guan; Heidi Shappell; Linda S. Davis; Greg Jack; Yu Shyr; Michael O. Koch; Scott B. Shappell; Matthew D. Breyer

Studies in human and animal models have shown that cyclooxygenase (COX)-2 is up-regulated in several epithelial carcinomas including colon, breast, and lung. To elucidate the possible involvement of COX-2 in human bladder cancer we examined the expression of COX isoforms in benign tissue and in bladder carcinoma specimens. Paraffin embedded tissues from 75 patients with urothelial carcinomas were immunostained with specific antibodies raised against COX-1 and COX-2. COX-1 expression was detected in smooth muscle cells in both benign and malignant bladders. COX-2 immunoreactivity was absent in benign tissue and in specimens with low-grade urothelial carcinoma (0/23). In contrast, expression of COX-2 was detected in malignant epithelial cells in 38% (17/47) of specimens with high-grade urothelial carcinomas. Expression of COX-2 in high-grade bladder cancer was confirmed by radioactive in situ hybridization using a COX-2-selective riboprobe. Both immunohistochemistry and in situ hybridization showed COX-2 expression in a small subset of malignant cells. COX-2 mRNA was also expressed in three out of seven malignant urothelial cell lines. These data demonstrate elevated expression of COX-2 in a high percentage of high-grade bladder carcinomas, suggesting a possible role of COX-2 in the progression of bladder urothelial carcinoma and supporting its potential as a therapeutic target in human bladder carcinoma.


American Journal of Pathology | 2005

Molecular Genetic Evidence for a Common Clonal Origin of Urinary Bladder Small Cell Carcinoma and Coexisting Urothelial Carcinoma

Liang Cheng; Timothy D. Jones; Ryan P. McCarthy; John N. Eble; Mingsheng Wang; Gregory T. MacLennan; Antonio Lopez-Beltran; Ximing J. Yang; Michael O. Koch; Shaobo Zhang; Chong Xian Pan; Lee Ann Baldridge

In most cases, small-cell carcinoma of the urinary bladder is admixed with other histological types of bladder carcinoma. To understand the pathogenetic relationship between the two tumor types, we analyzed histologically distinct tumor cell populations from the same patient for loss of heterozygosity (LOH) and X chromosome inactivation (in female patients). We examined five polymorphic microsatellite markers located on chromosome 3p25-26 (D3S3050), chromosome 9p21 (IFNA and D9S171), chromosome 9q32-33 (D9S177), and chromosome 17p13 (TP53) in 20 patients with small-cell carcinoma of the urinary bladder and concurrent urothelial carcinoma. DNA samples were prepared from formalin-fixed, paraffin-embedded tissue sections using laser-assisted microdissection. A nearly identical pattern of allelic loss was observed in the two tumor types in all cases, with an overall frequency of allelic loss of 90% (18 of 20 cases). Three patients showed different allelic loss patterns in the two tumor types at a single locus; however, the LOH patterns at the remaining loci were identical. Similarly, the same pattern of nonrandom X chromosome inactivation was present in both carcinoma components in the four cases analyzed. Concordant genetic alterations and X chromosome inactivation between small-cell carcinoma and coexisting urothelial carcinoma suggest that both tumor components originate from the same cells in the urothelium.


Analytical Chemistry | 2010

Cholesterol Sulfate Imaging in Human Prostate Cancer Tissue by Desorption Electrospray Ionization Mass Spectrometry

Livia S. Eberlin; Allison L. Dill; Anthony B. Costa; Demian R. Ifa; Liang Cheng; Timothy A. Masterson; Michael O. Koch; Timothy L. Ratliff; R. Graham Cooks

Development of methods for rapid distinction between cancerous and non-neoplastic tissues is an important goal in disease diagnosis. To this end, desorption electrospray ionization mass spectrometry (DESI-MS) imaging was applied to analyze the lipid profiles of thin tissue sections of 68 samples of human prostate cancer and normal tissue. The disease state of the tissue sections was determined by independent histopathological examination. Cholesterol sulfate was identified as a differentiating compound, found almost exclusively in cancerous tissues including tissue containing precancerous lesions. The presence of cholesterol sulfate in prostate tissues might serve as a tool for prostate cancer diagnosis although confirmation through larger and more diverse cohorts and correlations with clinical outcome data is needed.


Cancer | 2005

Improving the quality of life of patients with prostate carcinoma: a randomized trial testing the efficacy of a nurse-driven intervention.

R. Brian Giesler; Barbara A. Given; Charles W. Given; Susan M. Rawl; Patrick O. Monahan; Debra S. Burns; Faouzi Azzouz; Kristina M. Reuille; Sally Weinrich; Michael O. Koch; Victoria L. Champion

Treatments for clinically localized prostate carcinoma are accompanied by sexual, urinary, and bowel dysfunction and other sequelae that can result in significant distress and reduced well being. Methods capable of improving quality of life are needed that can be integrated into clinical practice. To address this need, a nurse‐driven, cancer care intervention was developed and tested.


American Journal of Pathology | 2002

Expression of group IIA secretory phospholipase A2 is elevated in prostatic intraepithelial neoplasia and adenocarcinoma.

Jiazhong Jiang; Blake Lee Neubauer; Jeremy R. Graff; Marcio Chedid; James E. Thomas; Neal W. Roehm; Shaobo Zhang; George J. Eckert; Michael O. Koch; John N. Eble; Liang Cheng

Phospholipase A2 (PLA2) enzymes release arachidonic acid from cellular phospholipids in a variety of mammalian tissues, including prostate. Group IIa secretory PLA2 (sPLA2) can generate arachidonate from cellular phospholipids. We examined the group IIa sPLA2 expression in benign prostatic tissues, prostatic intraepithelial neoplasia (PIN), and adenocarcinoma to determine whether sPLA2 expression is altered in the carcinogenesis of human prostatic cancer. Thirty-three of 74 total cases (45%) of benign prostatic tissue showed positive immunohistochemical staining for group IIA sPLA2, whereas 63 of 69 total cases (91%) of high-grade PINs and 70 of 78 total cases (90%) of adenocarcinomas gave positive results. Four of 10 cases of low-grade PIN showed positive immunoreactivity for sPLA2. The number of cells staining for sPLA2 was significantly less in benign epithelium (4%) and low-grade PIN (4%) compared to high-grade PIN (40%) or adenocarcinoma (38%) (P < 0.001). There was no significant difference between high-grade PIN and adenocarcinoma in the number of cells staining positively for sPLA2. The intensity of sPLA2 immunoreactivity was also different among benign prostatic tissue, low-grade PIN, high-grade PIN, and prostatic adenocarcinoma specimens. The malignant cells demonstrated more intense immunohistochemical staining (moderate to strong staining in 81% and 69% cases for high-grade PIN and adenocarcinoma, respectively) than benign glands (moderate staining in 11% of cases). No strong staining was observed in benign glands or low-grade PIN. Our data are consistent with the contention that group IIA sPLA2 expression is elevated in neoplastic prostatic tissue and support the hypothesis that dysregulation of sPLA2 may play a role in prostatic carcinogenesis.


Modern Pathology | 2005

Anatomic distribution and pathologic characterization of small-volume prostate cancer (<0.5 ml) in whole-mount prostatectomy specimens.

Liang Cheng; Timothy D. Jones; Chong Xian Pan; Ayana Barbarin; John N. Eble; Michael O. Koch

Some investigators consider small-volume prostate cancer (0.5 ml or less) without Gleason pattern 4/5 elements as clinically insignificant. The objective of this study was to characterize the anatomic distribution and pathologic features of small tumors (aggregate volume of 0.5 ml or less) in whole-mount prostatectomy specimens. Between 1999 and 2003, 371 consecutive patients underwent radical prostatectomy at the Indiana University Hospitals for localized prostate cancer. Patients who received hormonal or radiation therapy prior to the surgery were excluded from the study. A total of 62 specimens with total tumor volume of 0.5 ml or less were identified and included in this study. All specimens were embedded and whole-mounted. Tumor volume was measured using the grid method. The mean age at the time of surgery was 59 years (median, 61 years; range, 37–72 years). The mean preoperative prostate-specific antigen (PSA) was 6.5 ng/ml (range: 0.3–18 ng/ml). The mean prostate weight was 53 g (range: 16–132 g). The mean tumor volume was 0.29 ml (median, 0.35 ml; range, 0.02–0.48 ml). Tumor multifocality and bilaterality were present in 69 and 37% of cases, respectively. Three (5%) had positive surgical margins. The largest tumor was located in the peripheral zone, transitional zone, and central zone in 79, 16, and 5% of cases, respectively. The largest tumor was located in the anterior prostate in 10 cases (16%) and in the posterior prostate in 52 cases (84%). The distribution of Gleason scores was 5 (12 cases, 19 %), 6 (40 cases, 65 %), and 7 (10 cases, 16 %). One case had a primary Gleason pattern 4. None had extraprostatic extension, seminal vesicle invasion, or lymph node metastasis. Small-volume prostate cancers are often multifocal and bilateral, with predilection for the peripheral zone. Of these small-volume cases, 16% had Gleason pattern 4 and might, therefore, be clinically significant.


The Journal of Urology | 2009

Use of Ileum as Ureteral Replacement in Urological Reconstruction

Sandra A. Armatys; Matthew J. Mellon; Stephen D.W. Beck; Michael O. Koch; Richard S. Foster; Richard Bihrle

PURPOSE We reviewed indications and outcomes in patients undergoing ileal ureter replacement for ureteral reconstruction. MATERIALS AND METHODS Between December 1989 and September 2007, 105 patients underwent ileal ureter replacement, of whom 14 were excluded from study due to incomplete data. The remaining 91 patients (99 renal units) comprised the study cohort. RESULTS Mean patient age was 46.8 years and mean followup was 36.0 months. Indications for an ileal ureter were stricture following genitourinary surgery in 29 cases (31.9%), radiation induced stricture in 17 (18.7%), nonurological surgery iatrogenic injury in 16 (17.6%) and retroperitoneal fibrosis in 11 (12.1%). Only 4 patients (4.4%) had primary ureteral cancer. Long-term complications included anastomotic stricture in 3 patients (3.3%) and fistula in 6 (6.6%). Serum creatinine decreased or remained stable in 68 patients (74.7%) and hyperchloremic metabolic acidosis developed in 3. No patient complained of excessive urinary mucous production. CONCLUSIONS In 68.1% of patients indications for an ileal ureter included radiation induced stricture or iatrogenic injury. The ileal ureter is a reasonable option for long-term ureteral reconstruction with preserved renal function in carefully selected patients.


European Urology | 2014

Alvimopan Accelerates Gastrointestinal Recovery After Radical Cystectomy: A Multicenter Randomized Placebo-Controlled Trial

Cheryl T. Lee; Sam S. Chang; Ashish M. Kamat; Gilad E. Amiel; Timothy L. Beard; Amr Fergany; R. Jeffrey Karnes; Andrea Kurz; Venu Menon; Wade J. Sexton; Joel W. Slaton; Robert S. Svatek; Shandra Wilson; Lee Techner; Richard Bihrle; Gary D. Steinberg; Michael O. Koch

BACKGROUND Radical cystectomy (RC) for bladder cancer is frequently associated with delayed gastrointestinal (GI) recovery that prolongs hospital length of stay (LOS). OBJECTIVE To assess the efficacy of alvimopan to accelerate GI recovery after RC. DESIGN, SETTING, AND PARTICIPANTS We conducted a randomized double-blind placebo-controlled trial in patients undergoing RC and receiving postoperative intravenous patient-controlled opioid analgesics. INTERVENTION Oral alvimopan 12 mg (maximum: 15 inpatient doses) versus placebo. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS The two-component primary end point was time to upper (first tolerance of solid food) and lower (first bowel movement) GI recovery (GI-2). Time to discharge order written, postoperative LOS, postoperative ileus (POI)-related morbidity, opioid consumption, and adverse events (AEs) were evaluated. An independent adjudication of cardiovascular AEs was performed. RESULTS AND LIMITATIONS Patients were randomized to alvimopan (n=143) or placebo (n=137); 277 patients were included in the modified intention-to-treat population. The alvimopan cohort experienced quicker GI-2 recovery (5.5 vs 6.8 d; hazard ratio: 1.8; p<0.0001), shorter mean LOS (7.4 vs 10.1 d; p=0.0051), and fewer episodes of POI-related morbidity (8.4% vs 29.1%; p<0.001). The incidence of opioid consumption and AEs or serious AEs (SAEs) was comparable except for POI, which was lower in the alvimopan group (AEs: 7% vs 26%; SAEs: 5% vs 20%, respectively). Cardiovascular AEs occurred in 8.4% (alvimopan) and 15.3% (placebo) of patients (p=0.09). Generalizability may be limited due to the exclusion of epidural analgesia and the inclusion of mostly high-volume centers utilizing open laparotomy. CONCLUSIONS Alvimopan is a useful addition to a standardized care pathway in patients undergoing RC by accelerating GI recovery and shortening LOS, with a safety profile similar to placebo. PATIENT SUMMARY This study examined the effects of alvimopan on bowel recovery in patients undergoing radical cystectomy for bladder cancer. Patients receiving alvimopan experienced quicker bowel recovery and had a shorter hospital stay compared with those who received placebo, with comparable safety. TRIAL REGISTRATION ClinicalTrials.gov identifier NCT00708201.


The Journal of Urology | 2002

Major Complications in 213 Laparoscopic Nephrectomy Cases: The Indianapolis Experience

Tibério M. Siqueira; Ramsay L. Kuo; Thomas A. Gardner; Ryan F. Paterson; Larry H. Stevens; James E. Lingeman; Michael O. Koch; Arieh L. Shalhav

PURPOSE We assessed the incidence of and analyzed factors that may help prevent major complications and open conversion during laparoscopic nephrectomy at our institutions. MATERIALS AND METHODS We retrospectively analyzed all laparoscopic nephrectomies performed between August 1, 1999 and July 31, 2001. Data were stratified for nephrectomy type, intraoperative and postoperative complications. Conversion to open surgery was stratified for emergency versus elective procedures. RESULTS Of the 292 laparoscopic procedures performed at our institutions in 2 years 213 (73%) involved laparoscopic nephrectomy, including 84 live donor nephrectomies, 61 radical nephrectomies, 55 simple nephrectomies and 13 nephroureterectomies. A total of 16 major complications (7.5%) occurred, including access related, intraoperative and postoperative complications in 3, 9 and 4 cases, respectively. The conversion rate was 6.1% (13 patients), the transfusion rate was 1.9% and the mortality rate was 0.5% (1 death). Only 1 complication was related to simple laparoscopic nephrectomy, although this group showed the highest rate of elective conversion (7 of 8 elective conversions). Laparoscopic live donor nephrectomy showed the highest rate for emergency conversion (3 of 5 emergency conversions). CONCLUSIONS Our results reinforce the importance of thorough preoperative imaging, careful patient selection, surgeon experience and skill maintenance in laparoscopy as well as a low threshold for conversion to open surgery. This series provides additional evidence to support the evolution of laparoscopic nephrectomy into a standard of care.

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Heinrich Iro

University of Erlangen-Nuremberg

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