The Role of Prior Bladder Cancer on Recurrence in Patients Treated with Radical Nephroureterectomy

A novel nomogram for predicting extraurothelial recurrence in patients with upper urinary tract urothelial carcinoma after radical nephroureterectomy

PURPOSE

We aimed to establish and validate a nomogram for extraurothelial recurrence (EUR) after radical nephroureterectomy (RNU) for upper urinary tract urothelial carcinoma (UTUC).

METHODS

The data of 521 patients with UTUC after RNU from 2 medical centers were retrospectively studied and were used as training cohort (n = 301) and external validation cohort (n = 220). We used the least absolute shrinkage and selection operator (LASSO) to select variables for multivariable Cox regression, and included independent risk factors into nomogram models predicting EUR-free survival (EURFS). Multiple parameters were used to validate the nomogram, including the concordance index (C-index), the calibration plots, the time-dependent receiver-operator characteristics curve (ROC), and the decision curve analysis (DCA). Patients were stratified into three risk groups according to total points calculated by nomograms. The differences of EURFS in each group were analyzed by the Kaplan-Meier analysis.

RESULTS

Four variables were screened through LASSO regression. Bladder cancer history, Ki-67, lymphovascular invasion (LVI), and pathological T stage were shown to be independent predictive factors for EUR. The C-indexes of the model were 0.793 and 0.793 in training and validation cohorts, respectively. In comparison with prediction based on categorized pathological T stage, the DCA curves for 5-year EUR exhibited better performance. The 5-year EURFS rates were 92.2%, 63.8%, and 36.2% in patients stratified to the low-, medium-, and high-risk group.

CONCLUSION

Our study provided a new nomogram to predict the probability of EUR in UTUC patients underwent RNU, with perfect performance in discrimination ability and clinical net benefit. The application of the model may help urologists to choose proper treatment and monitoring.

Optimization of postoperative surveillance protocols in upper tract urothelial cancer: A retrospective cohort study

Upper tract urothelial carcinoma (UTUC) is an aggressive disease that is managed by radical or organ-sparing surgery. High recurrence rates require early detection and strict follow-up (FU) protocols. Recommendations are assigned to a low level of evidence. Our aim was to identify time-to-tumor recurrence, analyze the temporal relation to recommended FU regimens, and provide a critical proposal for further surveillance. This retrospective study included 54 patients receiving radical nephroureterectomy (RNU) in high-risk UTUC and 14 patients assigned to kidney-sparing surgery (KSS) with low-risk disease. FU surveillance protocols consisted of close intervals irrespective of the received type of surgery. In total, 68 patients were included with a median FU of 23 months. Mean overall survival (OS) was significantly shorter in RNU compared to KSS (P = .027). Recurrence in the bladder and/or upper urinary tract (UUT) was 57.1% in KSS and 38.9% after RNU (P = .241). Mean recurrence-free survival (RFS) was significantly shorter in RNU patients compared to KSS (22.4 vs. 47.9 months, P = .013), and 76.2% of the recurrences in the RNU group occurred in the first postoperative year. UUT recurrence was diagnosed after a median of 3.0 (RNU) and 25.0 (KSS) months. There was a frequent onset of metastases in the RNU group, with 85.7% in the first year compared to the KSS group with 50%. Multivariable regression analysis showed that the tumor stage was the parameter independently related to OS (P = .002), RFS (P = .008), and metastasis-free survival (MFS, P = .002). In conclusion, surveillance of UTUC should be adapted to real-time occurrence patterns. Strict imaging protocols are recommended in the first two years irrespective of the method of surgery. As recurrence is equally distributed over the years after KSS, cystoscopy should be offered regularly for five years and diagnostic URS for three years. After RNU, cystoscopies should be decreased to yearly intervals after year three. Contralateral UUT should also be examined after RNU.