Abstract
We found the article by Huang et al. to be intriguing, as it retrospectively examines the outcomes of laparoscopic nephroureterectomy (LNU) and robot-assisted radical nephroureterectomy (RANU) in treating upper urinary tract urothelial carcinoma (UTUC). 1 Involving 231 patients, the study found no significant differences between LNU and RANU in demographics, tumor characteristics, operative time, catheter time, or complications. However, RANU was associated with less intraoperative blood loss (30 vs 150 mL) and shorter postoperative hospital stays (8 vs 9 days). The 5-year overall survival, cancer-specific survival, and bladder recurrence-free survival rates were similar between both procedures. Despite RANU's advantages in certain areas, the authors urge caution in interpreting the results because of potential biases from case heterogeneity.
The authors deserve commendation for their efforts to shed light on this important topic. However, we identified few elements that might affect the generalizability of the conclusions and thus warrant further discussion. First, the pathology report presented in this study appears to deviate from the typical UTUC patient cohorts. With >90% of cases being high-grade and merely 1% to 3% having Carcinoma in situ, this significantly contrasts with the pathology reported in other case series. The study also did not identify any variant histology report, which has previously been demonstrated to affect oncologic outcomes. Considering the rarity of this disease, a centralized or dedicated genitourinary pathologist review can enhance the credibility of the results.
Second, perioperative neoadjuvant and adjuvant therapies could be confounding factors. The reported use of neoadjuvant chemotherapy (NAC) is surprisingly low (2%). Despite not having level I evidence, using NAC when indicated is essentially standard of care based on a recent phase 2 ECOG-ACRIN (EA8141) trial. 2 In addition, the study revealed that 35% to 40% of patients in each group had pT3/4, yet only 20% received adjuvant systemic treatment with unclear regimens. According to the Peri-Operative chemotherapy versus sUrveillance in upper Tract urothelial cancer (POUT) trial patients would have benefitted from adjuvant platinum-based therapy. 3 We acknowledge that the study period predates the publication of ECOG and POUT trials. Nonetheless, careful interpretation of the oncologic outcomes is warranted.
Third, as the authors mentioned in the limitation, the laparoscopic group, indeed, received heterogeneous treatments: whereas majority of the group received laparoscopic nephrectomy and open bladder cuff excision, a minority of patients received total LNU. These two treatments are technically and outcome-wise different. It is possible that the open bladder cuff excision portion in such a cohort have been the reason for increased blood loss and lengthier hospital stay in laparoscopic compared with robotic group.
Other limitations include the relatively short follow-up time, which may limit the validity of the projected 5-year oncologic outcome. Moreover, the use of Clavien–Dindo classification system for intraoperative complications needs be verified, as it is intended for postoperative complication measurement. A system such as EAUiaiC or ClassIntra, designed specifically for intraoperative complications, might be more suitable. 4,5
To conclude, although RANU shows advantages in certain areas, we echo the authors' caution in interpreting these results because of the limitations identified. We eagerly anticipate future studies to further investigate this crucial question.