Assessment of Ki-67 proliferation index in prognosis prediction in patients with nonmetastatic clear cell renal cell carcinoma and tumor thrombus.

PURPOSE: To determine the optimal cut-off value of Ki-67 for predicting the survival of patients with clear cell renal cell carcinoma (ccRCC) and tumor thrombus and to explore the correlation between Ki-67 expression and pathological features. PATIENTS AND METHODS: We retrospectively analyzed Ki-67 immunohistochemical staining of ccRCC and tumor thrombus resected from February 2006 to February 2022. The survival rate was evaluated using the Kaplan-Meier method. The optimal cut-off value of the Ki-67 expression for predicting survival was determined by the minimum P-value method. Clinicopathological data were compared based on Ki-67 status (low versus high expression). Univariate and multivariate Cox regression analysis was used to explore independent predictors. RESULTS: A total of 202 patients (median age, 58 years [IQR, 52-65 years], 147 men) with ccRCC and tumor thrombus were included in the study. The optimal cut-off value of Ki-67 for predicting survival was 30%. 159 (78.7%) and 43 (21.3%) patients were included in the low-expression and high-expression groups. Patients with Ki-67 high expression had significantly worse recurrence-free survival (P < 0.001) and cancer-specific survival (P < 0.001). Ki-67 high expression was associated with adverse pathological features, including tumor necrosis, ISUP nuclear grade, sarcomatoid differentiation, perirenal fat invasion, renal pelvis invasion, and inferior vena cava wall invasion (all P < 0.050). Ki-67 expression ≥ 30% (P = 0.016), tumor side (P = 0.003), diabetes (P = 0.040), blood loss (P = 0.016), inferior vena cava wall invasion (P = 0.016), and sarcomatoid differentiation (P = 0.014) were independent predictors of cancer-specific survival. CONCLUSION: The optimal cut-off level of Ki-67 in predicting the prognosis of ccRCC and tumor thrombus was 30%. The high expression of Ki-67 was associated with the aggressive pathological phenotype and poor prognosis.

Laparoendoscopic single-site urethrovesical anastomosis training in an economical porcine model.

PURPOSE: To develop an economical animal model for laparoendoscopic single-site surgery (LESS) urethrovesical anastomosis (UVA) training. MATERIALS AND METHODS: A homemade single-port device was used and the uterus cervix and the ileum were chosen to simulate UVA to reduce costs. Ten trainees were randomly divided into two groups: the conventional LESS UVA (CLUVA) group and the transurethral assistant LESS UVA (TALUVA) group. In TALUVA, a laparoscopic forceps was inserted through the urethra to assist operation after the bladder neck was disconnected, whereas CLUVA followed the conventional steps. Anastomosis time and knotting time were recorded, and the learning curves of both groups were analyzed. After training, questionnaires were given to the trainees to assess the difficulties and the satisfaction of the training. RESULTS: The final mean operating time significantly declined in both groups. Except for the first lesson, the trainees in the TALUVA group operated faster than those in the other group. The results from the questionnaires show that all trainees were satisfied with the training, and LESS UVA was considered more difficult in the CLUVA group than in the TALUVA group. CONCLUSIONS: The female porcine model for LESS UVA was feasible and cost-effective. TALVUA could effectively reduce the difficulties involved in LESS UVA.