AUA 2022: Impact of Node Count on Survival Outcomes of Lymph Node Dissection in non-Metastatic Upper Tract Urothelial Carcinoma: Analysis of the ROBUUST Registry

( The 2022 Annual Meeting of the American Urological Association was host to a podium session about upper tract transitional cell carcinoma. Kevin Hakimi presented results from the ROBUUST Registry evaluating the impact of node count on survival outcomes of lymph node (LN) dissection in non-metastatic upper tract urothelial carcinoma (UTUC).

The speaker began his presentation by noting that LN metastasis is found in 30-40% of patients with UTUC, however the benefits of LN dissection remain unclear. Current literature suggests that LN dissection in clinical node positive patients may not provide overall or cancer-specific survival benefit. There is no clear consensus on the template or extent of lymphadenectomy requirement in UTUC, particularly in clinically node negative patients. The impact of LN dissection in providing survival benefit in clinically node negative patients remains unclear.

The primary outcome of this study was thus to evaluate the extent of LN dissection in node negative patients and its impact on survival and oncologic outcomes. The secondary outcome was to attempt to more clearly delineate which patients are at risk for node positive disease.

This was a multicenter, retrospective analysis utilizing the ROBUUST (Robotic surgery for Upper Tract Urothelial Cancer Study) registry of UTUC patients undergoing a nephroureterectomy +/- LN dissection between 2006 and 2019.

Kaplan-Meier curves and multivariable analysis was conducted to assess predictors of survival outcomes.

Baseline patient characteristics are listed below. The three groups (LNx, LN0<10, LN0>=10) were well-balanced overall for baseline characteristics, with no significant differences in median clinical tumor size, positive margins, tumor grade or pathologic stage.

The following associations were seen between pN0 >=10 and oncologic outcomes:

  • All-cause mortality: HR 0.91 (95% CI: 0.55-1.59), p<0.001
  • Cancer-specific mortality; HR 1.69 (95% CI: 0.88-3.27, p=0.118)
  • Recurrence: HR 0.77 (95% CI: 0.60-0.97, P=0.029)

Factors associated with LN positivity included:

  • High grade: OR 12.14 (95% CI: 1.66-88.92, p=0.014)
  • Tumor size >=4.5 cm: OR 2.12 (95% CI: 1.26-3.57, p=0.005)

The speaker concluded as follows:

  • Lymph node dissection may confer a recurrence free survival advantage in LN negative patients with >=10 LNs removed
  • Tumor size>=4.5 cm and high clinical tumor grade predict pathologic LN positivity, which may aid with surgical planning  
Presented by: Kevin Hakimi, 4th year medical student, University of California in San Diego, San Diego, CA

Written by: Rashid Sayyid, MD, MSc – Urology Chief Resident, Augusta University/Medical College of Georgia, @rksayyid on Twitter during the 2022 American Urological Association (AUA) Annual Meeting, New Orleans, LA, Fri, May 13 – Mon, May 16, 2022.