Immunological studies on urinary bladder tumors of rats and mice.

Human neoplasms derived from the same tissue have been previously shown to have tumor associated antigens characterizing that tissue type. Evidence is now presented for the existence of analogous antigens common to both rat bladder papillomas and carcinomas, and for antigens common to mouse bladder carcinomas. Rats immunized with syngeneic urinary bladder papillomas, then challenged with a methylcholanthrene pellet inserted into the bladder, develop (4 to 6 months later) fewer primary bladder tumors than rats immunized with normal bladder tissue.

Long-term transplantability and morphological stability of three experimentally induced urinary bladder carcinomas in rats.

Three transitional cell carcinomas induced in Fischer 344 rats by a methylcholanthrene pellet or a foreign body inserted locally into the bladder have been serially transplanted in the syngeneic strain for up to 6.5 years. There have been no changes in the individual morphological characteristics of the tumors during this time. Cells cultured in vitro for varying numbers of passages reproduce regularly the morphology of each tumor when they are injected back into the animals and results from a microcytotoxicity assay for cellular immunity indicate that they retain a common, bladder tumor-specific antigen. These tumors are useful for research in turmo biology and are offered to other scientists seeking transplantable carcinomas for experimentation.

Combined 5-fluorouracil and irradiation for transitional cell carcinoma of the urinary bladder.

Thirty-four patients have completed treatment on a bladder-preservation protocol using primary irradiation combined with infusion 5-fluorouracil (5-FU). 4,000 cGy pelvic irradiation was delivered in 5 weeks, with 1,000 mg/m2/day of 5-FU administered as a 96 hr infusion on days 1-4 of week 1 and 4. After a 3-week rest period, patients eligible for cystectomy underwent cystoscopy and biopsy. Those with residual tumor underwent cystectomy, and those without tumor received an additional cycle of chemotherapy and irradiation. Patients ineligible for cystectomy for reasons medical, surgical, or refusal received a third cycle without the 4-week delay or re-evaluation. With a median follow-up of 18 months (range 2-45 months), and with 25/34 patients having T3 (16) or T4 (9) tumors, 17 patients are NED, 4 have died of intercurrent deaths, 7 have died with bladder cancer, and 6 are alive with tumor (2 confined to the bladder). The actuarial cancer-specific survival for the entire group of patients is 64% (+/- 12%) at 45 months, with a freedom from relapse of invasive cancer of 54% (+/- 10%). Twenty-four of the 34 patients retained intact bladders, with 20/24 reporting entirely normal voiding. Of 18 potential surgical candidates, 13/16 (81%) who underwent pathologic re-staging after 2 cycles of chemoradiotherapy had no histologic evidence of residual cancer. Of these 13 patients, 8 remain NED and 2/13 have locally recurrent non-invasive tumors only. Treatment was well-tolerated, with 28/34 patients having received 100% of the planned 5-FU and 34/34 having received greater than 80%. This regimen appears more successful than radiotherapy alone in achieving complete tumor responses, and is an attractive alternative for patients who are unable to receive more aggressive chemotherapy/radiation combinations.

Video-assisted minimally invasive mitral valve surgery.

OBJECTIVE: This study was done to determine the potential benefits of minimally invasive mitral surgery performed with intraoperative video assistance. METHODS: From May 1996 until March 1997, a minithoracotomy and video assistance were used in 31 consecutive patients undergoing mitral repair (n = 20) and replacement (n = 11). Their ages ranged from 18 to 77 years (59 +/- 2.6 years; mean +/- standard error of the mean). Ejection fractions were 35% to 62% (55% +/- 1.5%). Operations were done with either antegrade/retrograde (n = 10) or antegrade (n = 19) cold blood cardioplegia and a new transthoracic crossclamp or with ventricular fibrillation (n = 2). Peripheral arterial cannulation (n = 28) and pump-assisted right atrial drainage (n = 26) were used most often. RESULTS: No hospital deaths occurred, but the 30-day mortality was 3.2%. Complications included deep venous thrombosis and a phrenic nerve palsy in one patient each. No patient had a stroke or required reoperation for bleeding. Postoperative echocardiography showed excellent valve function in all but one patient. Cardiopulmonary bypass and arrest times averaged 183 +/- 7.2 and 136 +/- 5.5 minutes, respectively. Compared with 100 patients having conventional mitral valve operations, these patients had significantly shorter hospitalization times (8.6 +/- 0.5 vs 5.1 +/- 0.9 days, p = 0.05). Moreover, 81% of the later cohort were discharged between day 3 and 5 (3.6 +/- 0.2 days). Hospital charges (decreases 27%, p = 0.05) and costs (decreases 34%, p < 0.05) were less than in conventional operations. Patient follow-up suggested minimal perioperative pain and rapid recovery. CONCLUSIONS: Early results suggest that video-assisted minimally invasive mitral operations can be done safely. These methods may benefit patients through less morbidity, earlier discharge, and lower cost.

Studies of polyglycolic acid hollow self-retaining vasal stent in vasovasostomy.

A simple method of vasovasostomy using a unique hollow, biflanged, hydrolyzable, self-retaining intraluminal stent made of polyglycolic acid (PGA) was evaluated in rat and dog animal models. The stented vasovasostomy was compared with a modified two-layer technique in a randomized prospective trial in rats. Twenty of 22 vasovasostomies using the 0.8890 mm and 0.9398 mm stents were patent, whereas only 4 of 22 vasovasostomies using a modified two-layer anastomosis without a stent were patent (P less than 0.01). Eight dogs underwent implantation of the absorbable vasovasostomy stent on one side and two-layer vasovasostomy on the other. Scanning electron microscopy showed superior re-epithelialization and closer return to normal morphology in the stented vasovasostomies than with the conventional two-layer technique.

Sexually transmitted diseases and carcinogenesis.

Issues related to the development of cancer of the urogenital system in men and women and the possible role played by agents of sexually transmitted diseases are discussed. Research evidence supporting the role of specific viral agents in the etiology of cancer of the uterine cervix, penis, testis, prostate, and urinary bladder is presented. Also included is a discussion of the current speculations about the role played by agents of sexually transmitted diseases in acquired immune deficiency syndrome (AIDS).

Trocar site closure: a new and easy technique.

The GORE (W.L. Gore & Associates, Phoenix, AZ) Suture Passer, a new reusable fascial closure device, is one of the best devices on the market for closure of laparoscopic trocar site wounds. The technique for closure of fascia using this device is described. It is a cost-effective, safe, and easy.

Laparoscopic treatment of an appendiceal mucocele.

Appendiceal mucocele is a rare entity with a nonspecific preoperative presentation and is diagnosed intraoperatively in a majority of cases. The emphasis lies in accurate pathologic diagnosis, as the final treatment can differ depending on the malignant potential. The case presented was correctly diagnosed preoperatively. Laparoscopic exploration was both diagnostic and therapeutic. This case demonstrates the utility and safety of laparoscopy in the treatment of appendiceal masses.

Laparoscopic splenectomy at caesarean section.

The role of minimally invasive surgery continues to expand in all the specialties and subspecialties of surgery. At one time, obesity and pregnancy were considered a relative contraindication to laparoscopic surgery. With improved technology and skills, surgeons are able to operate on patients who were once considered to be at too high a risk for laparoscopic surgery. Herein, laparoscopic splenectomy performed at the time of Caesarean section is reported. This case demonstrates the safety and efficacy of laparoscopic splenectomy in a morbidly obese female in the immediate postpartum time.

Robotic Nissen fundoplication: alternative surgical technique for the treatment of gastroesophageal reflux disease.

The first robotic Nissen fundoplication using the da Vinci robotic surgical system was performed on a 56-year-old woman with a 20-year history of severe gastroesophageal reflux disease refractory to medical management. The recovery was uneventful, and follow-up continues.

Femoral hernia in children: an infrequent problem revisited.

Femoral hernias are of very rare occurrence at any age, but are exceedingly rare in the pediatric population. A 10-year survey, 1979-1989, of our experience with pediatric hernias produced a total of 1,134 inguinal hernias and 6 femoral hernias, supporting an incidence of 0.5% for femoral hernias in our population. The correct diagnosis was made in only two cases preoperatively. These two patients had undergone inguinal herniorrhaphies less than 6 months prior to presenting with recurrent groin masses. Femoral hernias were most frequently misdiagnosed as inguinal hernias. Inclusion of this entity in the differential diagnosis of groin masses, an accurate preoperative physical exam, and a careful surgical exploration will allow one to make the correct diagnosis and prevent unnecessary reoperations. In addition, early recurrence of a groin mass after inguinal exploration and herniorrhaphy should make one suspicious of a femoral hernia. At surgery, our recommendations include a simple infra-inguinal exploration medial to the femoral vessels when an inguinal hernia is unexpectedly not found at groin exploration and a Cooper's ligament repair when a femoral hernia is encountered. All six cases in our review were repaired with Cooper's ligament repair without complication.

Pulmonary embolism from a venous thrombosis distal to the popliteal vein.

A case of pulmonary embolism from a venous thrombosis distal to the popliteal vein is reported. This occurred despite venographic and ultrasound verification that the thrombus had not extended to the popliteal vein. The medical literature supports expectant treatment of "calf-only" venous thrombi. Our case clearly demonstrates that clinically significant pulmonary emboli can arise from calf vein thrombi without popliteal involvement.

Stomal obstruction of ileal conduits in children: a urodynamic study.

In an attempt to diagnose stomal obstruction before radiological evidence is present, urodynamic perfusion studies were done on 40 children with ileal conduit diversion. Residual urine, capacity, resting pressure and mean emptying pressure were recorded after perfusion of the conduit with normal saline at 10 ml. per minute. Emptying pressure appeared to be the most sensitive parameter of obstruction. Residual urine may be normal in early obstruction and may be increased in the presence of normal emptying pressures in atonic conduits.

Ileocecal bladder augmentation in myelodysplasia.

We discuss 14 children and adolescents with myelodysplasia who underwent bladder augmentation with the ileocecal segment. The bowel was not detubularized nor was the ileocecal valve intussuscepted. Urodynamic evaluation was performed before and after the procedure in 13 patients with a followup of 1 to 8 years. Postoperative capacity and compliance were normal but cecal contractions occurred in 8 patients despite adequate doses of anticholinergics. Reflux was demonstrated at capacity with a cecal contraction in 4 patients but upper tract dilatation and infection were not clinical problems. Three patients required reoperation for complications owing to ureteroileal stenosis and/or urinary tract calculi. Although the clinical results were satisfactory, detubularized segments of bowel with intussuscepted afferent loop valves to prevent reflux may resolve these problems in the future.

Tumor cell implantation following neodymium-YAG bladder injury: a comparison to electrocautery injury.

Recent clinical experience using the neodymium-YAG laser for the ablation of superficial bladder carcinoma seems to indicate a decreased local and second-site recurrence rate when compared to standard electrosurgical methods. Altered tumor cell implantation has been suggested as a mechanism explaining this phenomenon. The purpose of this study was to compare the effects of laser ablation and standard electrosurgical resection on tumor implantation. Each of three requisite steps in tumor cell implantation was assayed in an animal model system. The number of viable tumor cells liberated during ablation of a standardized lesion was 620% greater in the electrosurgically resected group compared to the laser irradiated group. No difference was observed in the qualitative or quantitative patterns of cellular adherence to a fulguration bladder injury compared to a laser bladder injury. The number of cells adhering to an injury site was shown to increase as a function of the cell concentration to which it was exposed. There was no difference between groups in occurrence of tumor at the injury site following exposure to an equal number of tumor cells. This study has demonstrated marked differences between electroresection and laser ablation in terms of the number of viable cells released during the course of tumor removal. This data, together with the absence of injury site differences, suggests it may play a role in the clinically observed differences in tumor recurrence rates.

On the mechanism of action of ribonuclease A: relevance of enzymatic studies with a p-nitrophenylphosphate ester and a thiophosphate ester.

It has been reported that His-119 of ribonuclease A plays a major role as an imidazolium ion acid catalyst in the cyclization/cleavage of normal dinucleotides but that it is not needed for the cyclization/cleavage of 3'-uridyl p-nitrophenyl phosphate. We see that this is also true for simple buffer catalysis, where imidazole (as in His-12 of the enzyme), but not imidazolium ion, plays a significant catalytic role with the nitrophenyl substrate, but both are catalytic for normal dinucleotides such as uridyluridine. Rate studies show that the enzyme catalyzes the cyclization of the nitrophenylphosphate derivative 47,000,000 times less effectively (kcat/kuncat) than it does uridyladenosine, indicating that approximately 50% of the catalytic free energy change is lost with this substrate. This suggests that the nitrophenyl substrate is not correctly bound to take full advantage of the catalytic groups of the enzyme and is thus not a good guide to the mechanism used by normal nucleotides. The published data on kinetic effects with ribonuclease A of substituting thiophosphate groups for the phosphate groups of normal substrates has been discussed elsewhere, and it was argued that these effects are suggestive of the classical mechanism for ribonuclease action, not the novel mechanism we have recently proposed. The details of these rate effects, including stereochemical preferences in the thiophosphate series, can be invoked as support for our newer mechanism.