Testing for urinary hyaluronate improves detection and grading of transitional cell carcinoma.

OBJECTIVE: The purpose of this study is to establish a method for the diagnosis and grading of transitional cell carcinoma (TCC), which is responsible for 90% of bladder tumors, using a recently developed ultrasensitive assay for the measurement of hyaluronan (HA). MATERIALS AND METHODS: Urine samples were collected prior to surgery (cystoscopy, transurethral resection for bladder cancer (TURBT), and cystectomy) in 350 patients. After the procedure, pathologic examination revealed that 160 patients had TCC. HA was measured directly in the urine by a noncompetitive enzyme-linked immunosorbent assay (ELISA)-like fluorometric assay. Using the receiver operator characteristic curve (ROC), t-test, Dunn test, Kruskal-Wallis test, and Mann-Whitney test, we evaluated the differences between groups (those with TCC vs. those without TCC). RESULTS: By analyzing the ROC curve, we chose a urinary HA cutoff value of 13.0 µg/l for indicating risk of TCC. Using the value this of 13.0 µg/l, we found that this test had an overall sensitivity of 82.3% and an overall specificity of 81.2%. The positive predictive value of this assay was 78.9%, the negative predictive negative value was 84.2%, and the predictive accuracy was 81.7%. Logistic regression analysis revealed that every 1 µg/l increase in HA increased a patient's likelihood of having TCC by 3.9%. The sensitivity of this test to detect superficial tumors was 76.6%, whereas its sensitivity for detecting invasive tumors was 94.6%. The urinary HA excretion of patients with TCC, classified according to the TNM staging system and the World Health Organization (WHO) grading system, were compared, and a significant difference was observed between the HA levels of patients with superficial tumors compared with invasive tumors (P = 0.005) as well as between patients with low- vs. high-grade carcinomas (P < 0.001). Patients with urinary HA levels >35 µg/l had a 4.63 times increased risk of having an aggressive, invasive, high grade tumor (P = 0.005). CONCLUSIONS: Our results support the postulate that urinary HA may be used as a tumor marker to aid in the diagnosis and grading of TCC. Additionally, more invasive tumors produce and release more HA in urine than superficial tumors, thus higher HA levels indicate more aggressive disease.

In-vitro renal shrinkage after hypertonic saline perfusion for organ removal during laparoscopic nephrectomy.

BACKGROUND AND PURPOSE: To evaluate the possibility of shrinking the kidney by perfusion with hypertonic solution to facilitate organ removal in laparoscopic surgery. MATERIALS AND METHODS: After 18 open nephrectomies (ONs) in 9 pigs, one of four saline solutions (5%, 7.5%, 10%, and 15%) was infused through a catheter into the renal artery for 5 minutes in four kidneys each. The volumes and weights of the kidneys were measured before and after renal perfusion; the kidneys were then sent for histologic evaluation. Eight ONs were performed, and the kidneys were removed from the abdominal cavity in a plastic bag in order to mimic organ entrapment during laparoscopy. The kidneys were perfused with hypertonic solution and were again put in a plastic bag and removed from the same animal's abdomen through another incision. The incisions were measured with calipers before and after extraction of the unperfused and perfused organs. RESULTS: The kidneys that underwent perfusion with 5% saline had the greatest decrease in both weight and volume, an average of 16% and 17.8%, respectively. The average incision needed for extraction of unperfused kidneys was 44.9 mm (range 40-58 mm), whereas the mean size of the incision needed to remove perfused kidneys was 26.6 mm (range 20-30 mm) (P < 0.001). The relative reduction in the necessary incision size therefore was 44.3% (range 33.3%-55%). CONCLUSION: Perfusion with 5% saline is able to shrink the kidney volume slightly with mild histologic changes. In the pig, it is possible to decrease the renal incision necessary for kidney removal by 44% using this method.

The Boatman's knot: a single knot for renal-vein ligation during laparoscopic nephrectomy: description of technique and evaluation of feasibility and safety.

BACKGROUND AND PURPOSE: The endovascular stapler is the standard of care for renal-vein ligation during nephrectomy, but recently, some reports have addressed the need for lowering the costs in the operating room. The authors describe the first use of "boatman's knot" in renal-vein ligation during laparoscopic nephrectomy and tests of its safety and feasibility. MATERIALS AND METHODS: Sixteen bilateral laparoscopic nephrectomies were performed in female pigs. On the right side, the renal vein was ligated with the boatman's knot, and on the left side, the vein was ligated with conventional intracorporeal technique. The knots were performed by the same surgeon at initial laparoscopic training. The time required to tie the knots was measured. After bilateral nephrectomy, a midline incision was created, and the bursting pressure of the knots was measured with a manometer by saline infusion into the vena cava. RESULTS: The average knot-completion time was 45 seconds (range 30-50 seconds), and the average time needed to carry out the conventional suture was 202.5 seconds (range 186-228 seconds). After renal-vein transection, there was complete hemostasis in all cases. The mean bursting pressure was 179.9 mm Hg (range 126-304 mm Hg). In five cases, the rupture site was in a lumbar vein previously sutured, while in three cases, the rupture happened in the vena cava itself. CONCLUSION: The boatman's knot is feasible, safe, easy to learn, and faster than conventional intracorporeal suturing. This technique may replace the endovascular stapler. However, its clinical applicability remains to be determined.

The "boatman's knot": a new option for renal hilum ligation during laparoscopic nephrectomy.

PURPOSE: The authors present and describe an original adaptation for the use of "boatman's knot" in renal vein ligation during laparoscopic nephrectomy. This procedure may replace the need for the endovascular stapler, which is considered the standard of care, but not available in several institutions in Brazil. The knot presented is also known as the "pig's knot" in several farms in Brazil. METHODS: Fourteen laparoscopic nephrectomies were performed by the same surgeon in a standard fashion in seven female pigs. Both the renal artery and vein were ligated using the "boatman's knot" as the only method for hemostasis with conventional intracorporeal technique. Two knots were applied in each artery and vein; one knot was tied proximally and the other distally. The vessels were then sectioned in between both knots. This technique is based on the intracorporeal confection of two loops by the right hand pair of dissectors with the help of the left hand. The arteries and the veins were then sectioned and the capability to accomplish full hemostasis was observed. RESULTS: All the laparoscopic nephrectomies were performed successfully. The "boatman's knot" was performed by the same surgeon with neither complications nor difficulties during the confection of the knot. In all cases hemostasis was fully achieved using only the "boatman's knot" as the hemostatic method. CONCLUSION: The "boatman's knot" is feasible and safe for hilum control during laparoscopic nephrectomy in pigs and total hemostasis can be achieved using it as the only method of hemostasis. However, the safety and the capacity of others to learn how to apply it should be tested before it may be advised to use it routinely.

The boatman's knot: a new option for renal hilum ligation during laparoscopic nephrectomy

OBJETIVO: Os autores apresentam e descrevem uma adaptação original para o uso do nó de barqueiro na ligadura da veia renal durante a nefrectomia laparoscópica. O procedimento pode substituir a necessidade da sutura mecânica endovascular, considerada o tratamento padrão, mas não disponível em muitas instituições no Brasil. Este nó é tembém conhecidocomo "nó de porco" em várias fazendas no Brasil. MÉTODOS: Quatorze nefrectomias laparoscópicas foram realizadas pou um único cirurgião utilizando a técnica padrão em sete porcas. A veia e a artéria renal foram ligadas utilizando o "nó de barqueiro" como o único método de hemostasia. Dois nós foram colocados tanto na artéria quanto na veia renal, um deles proximal e o outro distal, e os vasos seccionados entre os nós. Esta técnica é baseada a confecção intra-corpórea de duas alças pela mão direito com um par de pinças, com o auxílio da mão esquerda. Após a secção dos vasos, as condições da hemostasia foram observadas. RESULTADOS: Todas as nefrectomias laparoscópicas foram realizadas com sucesso. O "nó de barqueiro" foi realizado pelo mesmo cirurgião sem complicações nem dificuldades, obtendohemostasia completa em todos os casos como técnica única. CONCLUSÃO: O nó de barqueiro é uma técnica factível e segura para o controle do hilo renal durante a nefrectomia laparoscópica em porcos. Entretanto, a eficácia e segurança desta técnica deve ser avaliada por outros cirurgiões antes da recomendadção do emprego na prática clínica.