Tumour Size Is Associated With Growth Rates of >0.5 cm/Year and Delayed Intervention in Small Renal Masses in Patients on Active Surveillance

Authors

• Maximilian Pallauf
• Michael Rezaee
• Roy Elias
• Tina Wlajnitz
• Sean A Fletcher
• Joseph Cheaib
• Khalid Alkhatib
• Peter Chang
• Andrew A Wagner
• James M McKiernan
• Mohamad E Allaf
• Phillip M Pierorazio
• Nirmish Singla

Language

English

Publication Date

5-1-2025

Journal

BJU International

DOI

10.1111/bju.16651

PMID

39873312

PMCID

PMC11975477

PubMedCentral® Posted Date

5-1-2026

PubMedCentral® Full Text Version

Author MSS

Abstract

Objective: To evaluate the association between tumour size and the growth rate (GR) of small renal masses (SRMs) in patients managed by active surveillance (AS).

Materials and methods: We queried the prospective, multi-institutional Delayed Intervention and Surveillance for Small Renal Masses (DISSRM) registry for patients on AS with an imaging interval of ≥6 months, identifying 456 patients. We tracked tumour size over time; a GR >0.5 cm/year was defined as a GR event. We used multivariable recurrent events and time-to-event Cox regression modelling to evaluate the association between tumour size and GR events (primary outcome) and tumour size and delayed intervention (DI; secondary outcome). We tested tumour size as a continuous variable and dichotomised tumour size by predefined (2-cm) and calculated (2.9-cm) cutoffs. We calculated the cutoff using maximally selected rank statistics and time to progression, defined according to the DISSRM registry.

Results: The median (interquartile range) follow-up of patients on AS was 40.1 (26.4-71.2) months, during which 128 patients (28%) had ≥1 GR event, and 80 (18%) underwent DI. Larger tumour size was an independent predictor for GR events and DI when tested as a continuous and a dichotomous variable in multivariable analyses (all P < 0.05). The association was strongest when accounting for the change in tumour size over time and when applying the 2.9-cm cutoff. The study is limited by the mixed tumour pathology inert to SRMs.

Conclusion: Larger tumour size was independently associated with GR events and DI for patients with SRMs on AS. A 2.9-cm cutoff may provide valuable information for patient counselling.

Keywords

Humans, Kidney Neoplasms, Female, Male, Watchful Waiting, Middle Aged, Aged, Tumor Burden, Prospective Studies, Disease Progression, Registries, Time Factors, Carcinoma, Renal Cell Carcinoma, Small Renal Mass, Active Surveillance, Growth Kinetics

Published Open-Access

yes

Recommended Citation

Pallauf, Maximilian; Rezaee, Michael; Elias, Roy; et al., "Tumour Size Is Associated With Growth Rates of >0.5 cm/Year and Delayed Intervention in Small Renal Masses in Patients on Active Surveillance" (2025). Faculty, Staff and Student Publications. 4105.
https://digitalcommons.library.tmc.edu/uthmed_docs/4105