BACKGROUND: Pathological stage and grade of renal pelvis urothelial carcinoma (RPUC) are difficult to estimate before radical nephroureterectomy (RNU). OBJECTIVE: To examine tumor size as an independent predictor of muscle-invasive and/or non-organ-confined rates of RPUC at RNU. DESIGN, SETTING, AND PARTICIPANTS: Within the Surveillance, Epidemiology and End Results (SEER) database (2004-2016), we identified nonmetastatic RPUC at RNU. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: First, we examined stage and grade distributions. Second, two separate univariable and subsequent multivariable logistic regression models (LRMs) were fitted to test the association between tumor size and the rate of (1) muscle-invasive or higher (pT2-4N0-2) and (2) non-organ-confined (pT3-4N0-2) RPUC at RNU. RESULTS AND LIMITATIONS: Of 4657 patients, 3052 (65.5%) had pT2-4N0-2 and 2382 (51.2%) pT3-4N0-2 RPUC at RNU. The median tumor size was 3.7 cm (interquartile range 2.5-5.0). The high-grade RPUC rate ranged from 71.1% to 87.2% (p < 0.001) among SEER registries. Conversely, no differences were recorded for stage (p > 0.05) or tumor size (p = 0.1) across all registries. Rates of pT2-4N0-2 and pT3-4N0-2 RPUC increased with tumor size. Specifically, for tumor size intervals from 0.1-1.0 cm to 9.1-10.0 cm, the pT2-4N0-2 rate ranged from 45% to 83% and the pT3-4N0-2 rate ranged from 23% to 75%, respectively (both p < 0.001). In multivariable LRMs, tumor size (in 1-cm units) was an independent predictor of pT2-4N0-2 (odds ratio [OR] 1.25; p < 0.001) and pT3-4N0-2 (OR 1.30; p < 0.001) disease at RNU. CONCLUSIONS: Tumor size is a key predictor of muscle-invasive or non-organ-confined RPUC. Greater tumor size directly and virtually linearly predicts a higher rate of invasive or non-organ-confined RPUC at RNU. PATIENT SUMMARY: For patients with cancer in urinary tract cells lining the kidney, larger tumor size predicts worse stage of the disease at surgery.

Cancer Prognostics and Health Outcomes Unit Division of Urology University of Montréal Health Center Montréal Canada

Cancer Prognostics and Health Outcomes Unit Division of Urology University of Montréal Health Center Montréal Canada; Department of Urology IRCCS Ospedale San Raffaele Milan Italy

Cancer Prognostics and Health Outcomes Unit Division of Urology University of Montréal Health Center Montréal Canada; Department of Urology University Hospital Frankfurt Frankfurt am Main Germany

Cancer Prognostics and Health Outcomes Unit Division of Urology University of Montréal Health Center Montréal Canada; Martini Klinik Prostate Cancer Center University Hospital Hamburg Eppendorf Hamburg Germany

Department of Urology Comprehensive Cancer Center Medical University of Vienna Vienna Austria; Department of Urology Weill Cornell Medical College New York NY USA; Department of Urology University of Texas Southwestern Dallas TX USA; Department of Urology 2nd Faculty of Medicine Charles University Prague Czech Republic; Institute for Urology and Reproductive Health 1 M Sechenov 1st Moscow State Medical University Moscow Russia; Division of Urology Department of Special Surgery Jordan University Hospital The University of Jordan Amman Jordan

Department of Urology IRCCS Ospedale San Raffaele Milan Italy

Urology Unit Department of Neurosciences Reproductive Sciences and Odontostomatology University of Naples Federico 2 Naples Italy

Urology Unit Department of Neurosciences Reproductive Sciences and Odontostomatology University of Naples Federico 2 Naples Italy; Cancer Prognostics and Health Outcomes Unit Division of Urology University of Montréal Health Center Montréal Canada

Urology Unit Scuola Medica Salernitana Department of Medicine and Surgery University of Salerno Salerno Italy

References provided by Crossref.org

Upper Tract Urothelial Carcinoma: A Narrative Review of Current Surveillance Strategies for Non-Metastatic Disease

A Systematic Review and Meta-Analysis of Prognostic Nomograms After UTUC Surgery

Comparison between 1973 and 2004/2016 World Health Organization grading in upper tract urothelial carcinoma treated with radical nephroureterectomy