Rat model for carcinogenesis in ureterosigmoidostomy.

A rat model is used to study the carcinogenesis that occurs when urine is surgically diverted into the fecal stream, as in ureterosigmoidostomy. Adenocarcinoma of the colon occurs adjacent to the urine inlet. It is completely prevented by proximal diversion of the feces, implying that fecal carcinogens are activated locally by the urine or the urothelium.

Sequential isologous organ transplantation in inbred rats: pancreaticoduodenal transplants.

A total of 847 inbred Lewis rats of mixed sex were used in this pancreaticoduodenal (Pd) donor aging study. Pd grafts were taken from 9- to 12-month-old donors and transplanted into 3-month-old recipients (thus, the first generation Pd graft, or 1 Pd). After 9 to 12 months, the same Pd grafts were again harvested and transplanted into 3-month-old rats (thus the 2 Pd generation). This cycle was repeated to obtain the 3, 4, and 5 Pd series. Sequential transplantation was able to extend the Pd grafts' mean survival time to 32 months for fourteen 4 Pd grafts, and to 39.2 months for four 5 Pd grafts (the longest lived graft survived for 42 months). The pancreas and duodenal sections of the grafts remained normal throughout the entire study. However, the aortic sections of the grafts (which were harvested to include the superior mesenteric and celiac arteries) all exhibited moderate to massive atherosclerotic changes by the 5 Pd mean survival age of 39.2 months. Such histological changes commenced even before 21 months of Pd graft age in some animals, gradually progressing to dilation of the aorta (and subsequent narrowing of aortic tributaries), as well as formation of an eggshell-like inner membrane shielding the aortic intima, by 42 months. Such atherosclerotic changes precluded transplantations beyond the 5 Pd series.

Visualization of canine and human prostatic lymph nodes following intraprostatic injection of technetium-99m-antimony sulfide colloid.

Clinically occult lymph node metastases are a frequent finding in patients with carcinoma of the prostate. At present, lymph node dissection is the only reliable method of detecting local nodal spread; we have investigated a nonsurgical technique for demonstrating nodes using intraprostatic injections of 99mTc-Sb2S3. 99mTc-Sb2S3 (1.0 mCi/0.1--0.2 ml) was injected into the prostate glands of nine male mongrel dogs. Scintillation camera images revealed from one to four lymph nodes in each animal with earliest nodal visualization at 1 hour. A study performed on a 64-year-old man with prostatic cancer allowed visualization of seven pelvic lymph nodes, all of which were found to be histologically normal. The simplicity of this technique suggests the potential for both pre- and intraoperative identification of the prostatic lymph nodes. Clinical trials presently underway will allow assessment of the sensitivity and specificity of this technique for the detection of nodal metastases.

Resistance to intravenous tumor metastases in the athymic nude mouse: a paradoxic response.

The role of the host immune response in the abatement or prevention of tumor metastasis is unclear. To investigate possible interaction of lymphocytes with tumor cells, the F10 subline of the B16 melanoma was studied after subcutaneous or intravenous injection in original host C57BL/6 mice, Swiss nude mice, and BALB/c nude mice. The F10 tumor grew rapidly after subcutaneous injection in all strains of mice. Although florid pulmonary metastases were detected in the lungs of C57BL/6 mice after intravenous inoculation, both strains of nude mice were markedly resistant to the development of pulmonary metastases (P less than 0.001). Labeling of the B16 F10 melanoma cells with 3H-thymidine demonstrated that the kinetics of tumor cells after intravenous inoculation were similar in C57BL/6 mice and nude mice. Increased natural killer (NK) activity in the nude mouse play an important role in the prevention of pulmonary metastases.

Congenital penile curvature without hypospadias.

Congenital curvature of the penile shaft without hypospadias is a rare problem that poses cosmetic and functional disability. It is caused by disparate growth of the penile corpora. Surgical repair of 7 cases is reviewed, with follow-up of two to eight years. The results of these 7 cases are added to 13 other cases reported previously. The Nesbit technique was used with the modification of (1) preserving the dorsal neurovascular bundle to avoid anesthesia and lymphedema of the glans in selected cases, and (2) intraoperative use of saline-induced erections and Allis clamp " tucks" of the tunica albuginea to insure a satisfactory repair.

Topical testosterone therapy for penile growth.

Three prepubertal males were treated with daily applications to the penis of 5 per cen topical testosterone cream. Penile growth occurred in all 3 patients. Serum testosterone values rose dramatically in 2 of the patients. Topical testosterone probably causes penile growth via its systemic action, not merely through its local effect.

Live donor nephrectomy.

Donor nephrectomy was performed on 39 living related renal donors. The preoperative evaluation, surgical technique, and postoperative follow-up are presented. Major or minor complications developed in 23 per cent of the patients and included acute myocardial infarction, brachial plexus injury, acute glomerulonephritis, ileus, pneumonia, and urinary tract infection. All complications had resolved by six months postoperatively.

Medical therapy of experimental infection stones.

Struvite bladder calculi were induced in rats with an intrarenal injection of urease-producing human T mycoplasma strain T960. Acetohydroxamic acid was effective in inhibiting calculous formation. Methylene blue, tetracycline, orthophosphate, diphosphonate, and hydrochlorothiazide had no inhibitory effect.

Correlation of sperm granulomas and sperm autoantibodies in inbred rats.

The relationship between sperm granulomas and antisperm antibodies is speculative. Some investigators believe that sperm granulomas are the result of humoral sensitization, whereas others doubt that they represent an immunologic phenomenon at all. We performed transabdominal bilateral vasectomies by ligation or transection in Brown Norway, Lewis, Fischer, and Sprague-Dawley rats. These strains are known to differ in incidence of antisperm antibody formation following vasectomy. Serum was obtained monthly for determination of antibodies by indirect immunofluroescence. Animals were killed at 6 months and examined for the presence of antisperm antibodies and sperm granulomas. Both antibodies and granulomas were found in 71% of Brown Norway rats. Granulomas were found in all rats of other strains, whereas the incidence of antibodies ranged from 25% to 50%. Thus a specific immunologic relationship between sperm granulomas and antisperm antibodies has not been confirmed.

Carcinogenesis in ureterosigmoidostomy.

Both clinical and experimental observations establish that an adenocarcinoma of the colon is likely to occur at the suture line of ureterosigmoidostomy. The carcinogenesis depends on the initial presence of urine, feces, urothelium, and colonic epithelium in close apposition at a healing suture line. It does not occur in isolated colon loops used for urinary diversion. In our rat model, tumors were completely prevented by interposing ileum between the urothelium and colon. Clinical prevention requires that accurate hospital registries of patients at risk be established and that repeated annual colonoscopy be carried out on all of them.

Retrograde brushing and nephroscopy in the diagnosis of upper-tract urothelial cancer.

Very selected cases of upper-tract urothelial cancer benefit from diagnostic evaluation with retrograde brush biopsy and with operative nephroscopy. The selection of cases, techniques, results, and complications are presented.

Nephroscopy.

Nephroscopy has become an increasingly important adjunctive procedure in the diagnosis and treatment of patients with suspected calyceal calculi, essential renal hematuria, and selected forms of renal tumors. Great advances have been made in the instrumentation and technical aspects of the procedure, and it is hoped that further progress in these areas will render nonoperative renal endoscopy useful even in cases of renal hematuria and infected kidneys.

Posterior lumbotomy: surgery for upper tract calculi.

Posterior lumbotomy, modified by the adjuvant use of nephroscopy and postoperative stents, is presented as a preferred approach to upper ureteral, pelvic, or caliceal calculi. Its limited morbidity, brief hospitalization, brief operative time, and total efficacy of removal of calculi are the standards with which newer techniques described in this symposium must be compared.

Vanishing pancreatic grafts.

Comparison of pancreaticoduodenal transplants (PDT) and duct-ligated pancreas transplant (DLPT) were performed using syngeneic and allogeneic studies in rats. Both DLPT and PDT allogeneic grafts showed mild rejection. DLPT groups showed disorganized pathology and acini replaced by fat. Eventually, massive fibrosis was seen in the Islets of Langerhans, as well as rejection cellular infiltrates. In both PDT groups, normal histology was observed in the same period. Thus the effect of duct occlusion is highly detrimental for the grafts.