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A J Pantuck

Publications and source records attributed to A J Pantuck.

49 records · Page 3Linked to original sources
PubMed1999

Prospective evaluation of endorectal magnetic resonance imaging to detect tumor foci in men with prior negative prostastic biopsy: a pilot study.

PURPOSE: Prostate cancer foci have a characteristic appearance on endorectal magnetic resonance imaging (MRI) which might be useful for prostate cancer detection. In this pilot study the ability of endorectal MRI to detect prostate cancer foci prospectively in men at risk for a malignant prostatic neoplasm is assessed. MATERIALS AND METHODS: Endorectal MRI was performed in 33 consecutive men with 1 or more prior negative prostatic biopsies. All studies were read by 2 MRI dedicated study radiologists in consensus before and after receiving patient clinical data. Areas of interest on endorectal MRI were mapped as low, moderate or high suspicion for carcinoma on a prostate model. Directed needle biopsy cores of the prostate were obtained based on this model, and the histopathological findings were compared with MRI results. RESULTS: Carcinoma was detected in 7 of 33 men (21.2%) on post-MRI biopsy, including 1 of 18 (5.6%) with low, 1 of 8 (12.5%) with moderate and 5 of 7 (71.4%) with high suspicion MRI. The site of positive biopsy correlated correctly with the area of suspicion on MRI in 85.7% of cases. Overall, endorectal MRI had 40% positive predictive value (moderate or high suspicion), 94.4% negative predictive value (low suspicion) and 69.7% accuracy. On multivariate analysis positive endorectal MRI was associated with an 11.3-fold risk of positive biopsy. CONCLUSIONS: Endorectal MRI may effectively stratify patients with prior negative prostatic biopsy into low, moderate and high risk groups for a malignant prostatic neoplasm, and may improve our ability to identify prostatic tumor foci prospectively.

Aged↗
PubMed1999

Endovascular stent graft for management of ureteroarterial fistula after orthotopic bladder substitution.

We describe the first case of an ureteroarterial fistula developing after orthotopic neobladder substitution and its minimally invasive management using endovascular stent grafting. We outline the risk factors for the development of ureteroarterial fistulae and trace the evolution of diagnostic and therapeutic modalities used in the management of these life-threatening complications. Minimally invasive management with endovascular stent grafting and exclusion of two pseudoaneurysms in the iliac artery system was performed successfully. After successful endovascular exclusion of two pseudoaneurysms, the patient's hematuria resolved and he recovered fully. Three-dimensional computed tomography performed 3 months later documented a patent aortoiliac arterial system without evidence of pseudoaneurysm or endovascular leak. Ureteroarterial fistula after orthotopic bladder substitution was managed with an endovascular stent graft without the need for extra-anatomical vascular bypass. Early recognition, stabilization, and angiographic evaluation followed by this minimally invasive technique may avoid open operative repair and attendant morbidity.

Cystectomy↗
PubMed1998

The monoclonal antibody 7E12H12 can differentiate primary adenocarcinoma of the bladder and prostate.

OBJECTIVE: To determine if the monoclonal antibody 7E12H12, which reacts with a 40 kDa protein in normal human enterocytes and has been shown to be a marker for intestinal metaplasia and adenocarcinoma arising in the bladder, could assist in distinguishing prostatic, urachal and vesical adenocarcinoma, using a sensitive immunohistochemical assay. MATERIALS AND METHODS: Fifteen primary prostatic adenocarcinomas and five adenocarcinomas of the urinary bladder were selected for a retrospective evaluation. The monoclonal antibody 7E12H12 (IgM isotype) was used in an immunoperoxidase assay to survey formalin-fixed, paraffin-embedded archival tissue specimens. RESULTS: All vesical adenocarcinomas reacted positively with the antibody, regardless of grade; none of the 15 prostatic specimens reacted positively in either the benign or malignant glandular epithelium. CONCLUSION: The monoclonal antibody 7E12H12 can differentiate primary adenocarcinoma of the bladder from secondary adenocarcinoma arising in the prostate and may be a useful tool in diagnostic pathology.

Adenocarcinoma↗
PubMed1997

Adenocarcinoma of the urachus and bladder expresses a unique colonic epithelial epitope: an immunohistochemical study.

PURPOSE: Primary adenocarcinoma of the bladder is a rare neoplasm whose histogenesis is poorly understood. Current data support the concept that adenocarcinoma of the bladder and urachus evolves from zones of intestinal metaplasia that become dysplastic and invasive. To address this hypothesis further we determined the immunoreactivity of benign and malignant epithelial tissue from the bladder and urachus with a monoclonal antibody that is reactive with colonic epithelium to evaluate the presence of a common reactive epitope. MATERIALS AND METHODS: The monoclonal antibody 7E12H12 (IgM isotype), developed against a colonic epithelial protein, was used in an immunoperoxidase assay to survey formalin fixed, paraffin embedded archival tissue specimens. A total of 26 specimens obtained by endoscopic biopsy or extirpative surgery, including benign and malignant bladder and urachal epithelial abnormalities, was chosen for retrospective evaluation. RESULTS: All adenocarcinoma reacted positively regardless of the histological variant, differentiation, or bladder or urachal origin. In contrast, transitional cell and squamous cell carcinomas were nonreactive. Also, the pattern of reactivity in tissues that contained benign epithelial proliferations suggested a stepwise transition with no reactivity in normal urothelium or Brunn's epithelial nests, rare staining of cystitis cystica, and uniformly positive reactivity in cystitis glandularis and frank colonic intestinal metaplasia of the bladder and urachus. CONCLUSIONS: The shared, aberrant phenotypic expression of a unique colonic epitope in benign epithelial metaplasia, and adenocarcinoma of the bladder and urachus suggests a common underlying pathway toward adenocarcinoma in cystic and urachal adenocarcinoma. The implications for diagnostic pathology are discussed.

Adenocarcinoma↗
PubMed1997

Routine stentograms are not necessary before stent removal following radical cystectomy.

PURPOSE: Although ureteral stents have significantly reduced perioperative complications of urinary diversion, there is no universal agreement regarding their postoperative management. As part of an effort to eliminate unnecessary studies and hospital costs for radical cystectomy, we recently reviewed our experience with postoperative radiological stent studies to determine their clinical use and cost. MATERIALS AND METHODS: A retrospective examination of medical records and radiographic studies was performed for 96 patients undergoing cystectomy and urinary reconstruction between 1989 and 1996. All patients were stented at the time of surgery. Of the patients 51 underwent bilateral retrograde "stentograms" performed under fluoroscopic guidance before stent removal to evaluate for obstruction or urine leak as dictated by the preference of the primary surgeon in each case. A total of 41 evaluable patients did not undergo stentograms. RESULTS: In this study 102 stent injections were performed on 51 patients before stent removal. No patients were found to have ureteral obstruction at the ureterointestinal anastomosis, while 1 (0.98%) had a clinically silent anastomotic leak that healed with conservative measures. Complications directly attributable to the stent studies, including episodes of urosepsis, were noted in 9 patients (17.6%). Nine additional leaks were diagnosed in this cohort by other means. Half of all leaks were evident clinically and 60% of this group required further invasive procedures. All clinically silent leaks healed with conservative measures. Of 41 evaluable patients who did not undergo stentograms leak following stent removal developed in only 2 and both healed with conservative measures. The additional cost of detecting a single anastomotic leak with routine stentograms is estimated to be $58,000. CONCLUSIONS: Routine evaluation of the ureterointestinal anastomosis with stentograms before stent removal is unnecessary, costly and may in fact increase patient morbidity.

Aged↗
PubMed1996

Penile replantation using the leech Hirudo medicinalis.

A 37-year-old chronic schizophrenic man underwent penile replantation after complete autoamputation using a kitchen knife. We report the first case of using medicinal leeches to salvage a penile replant after the development of postoperative venous congestion.

Adult↗
PubMed1996

Diagnosis and management of malignant perirenal schwannoma.

Malignant retroperitoneal schwannoma is an extremely rare tumor, with only six cases previously reported occurring in the perirenal space. We herein report the seventh case. A 50-year-old woman presented with an abdominal mass suggestive of renal cell carcinoma by standard preoperative evaluation. The tumor required surgical exploration and pathologic evaluation for diagnosis. The final histologic diagnosis was made with the aid of electron microscopy and immunohistochemical staining with antibodies for S-100 protein.

Basement Membrane↗
PubMed1995

Vena cava resection during post chemotherapy lymphadenectomy for testis tumor.

Two patients underwent retroperitoneal lymphadenectomy after chemotherapy for non-seminomatous germ cell testis tumor. A dense desmoplastic tissue reaction between the infrarenal vena cava and perivascular lymphatic tissue prohibited removal of the nodal packet from the vena cava in both cases. We herein discuss two techniques for vena cava resection in these difficult cases.

Adult↗
PubMedDate not supplied

Occult bilateral ectopic vaginal ureters causing urinary incontinence: diagnosis by computed tomography.

Diagnosis of an ectopic, infrasphincteric ureter can be difficult because the renal moiety drained by the ectopic ureter is often small and functions poorly. We present a 6-year-old girl with urinary incontinence caused by bilateral vaginal ectopic ureters that were not seen on excretory urography or renal sonography and were diagnosed only by contrast-enhanced computerized tomography.

Child↗
PubMedDate not supplied

Actinomycin D and gemcitabine synergistically sensitize androgen-independent prostate cancer cells to Apo2L/TRAIL-mediated apoptosis.

The cytotoxic efficacy and kinetics involved in sensitization of Apo2L/TRAIL-resistant, androgen-independent prostate cancer cells to Apo2L/TRAIL or tumor necrosis factor-alpha or Fas ligand-mediated apoptosis were tested using subclinical concentrations of actinomycin D, paclitaxel, cisplatinum, gemcitabine, and radiation in CL-1, LNCaP, DU-145, and PC3 prostate cancer cell lines. CL-1 cells expressed all four Apo2L/TRAIL receptors and were resistant to Apo2L/TRAIL-mediated apoptosis (1-5,000 ng/mL) and to the sensitizers when given alone. Pretreatment with actinomycin D followed by Apo2L/TRAIL or tumor necrosis factor-alpha or anti-Fas CH-11 monoclonal antibody, but not in the reverse order, induced apoptosis in all cell lines. Synergistic sensitization in CL-1 cells was shown also with gemcitabine but not with cisplatinum, VP-16, paclitaxel, or radiation. Incubating the Apo2L/TRAIL-resistant CL-1, LNCaP, DU-145, and PC3 cell lines with 100 ng/mL actinomycin D for 4 hours followed by Apo2L/TRAIL for 24 hours resulted in 45.4 +/- 10.3%, 58.8 +/- 3.6%, 53.4 +/- 1.4%, and 84.2 +/- 8.4% apoptosis, respectively. Prolonging the sensitization time to 24 hours followed by 20 hours of incubation with Apo2L/TRAIL further enhanced the killing activity against CL-1 cells to 89 +/- 1% (delta = 60%, synergistic ratio = 3.1). This killing has a biphasic pattern that was contributed to by apoptosis (83%) and necrosis (17%) at 10 hours (peak) and 40% and 60%, respectively, at 20 hours. These results suggest that prostate cancer cells' resistance to Apo2L/TRAIL-mediated apoptosis can be reversed and synergy is achieved by sensitization of tumor cells with subclinical concentrations of actinomycin D or gemcitabine and may be useful clinically for the treatment of metastatic hormone- and drug-refractory prostate cancer.

Androgens↗