Resident Division of Urology, Department of Surgery, Perelman School of Medicine, University of Pennsylvania PHILADELPHIA, PA, United States
Background: Renal transplant candidates are often referred to urology for treatment of a small renal mass (SRM) suspicious for a cT1a renal cell carcinoma. Active surveillance (AS) for SRMs may minimize morbidity of treatment, but outcomes of AS in renal transplant candidates and immunocompromised patients have not been established.
Methods: The multi-institutional Delayed Intervention and Surveillance for Small Renal Masses (DISSRM) prospective registry, including patients with SRMs ≤ 4 cm from 2009 onwards, was reviewed up to December 2021. Patients with end-stage renal disease (ESRD) or immunocompromised status (prior organ transplant, immunosuppressive medications, leukemia or lymphoma, HIV or AIDS) were included. For included patients, the following variables were extracted: follow up period, mass size at diagnosis, mass growth rate, timing and type of intervention if applicable, and development of metastases.
Results: Of 15 patients with ESRD (including 8 transplant candidates), the mean size of the SRM at diagnosis was 2.3 cm, and over a mean follow up period of 2.4 years, the mean SRM growth rate was 0.1 cm/year. Six patients (40%) underwent either intermediate (4 patients) or delayed intervention (2 patients). Of 11 patients (60%) remaining on surveillance, none developed metastases. Of 44 immunosuppressed patients, the mean size of the SRM at initial diagnosis was 1.9 cm, and over a mean follow up period of 3.5 years, the mean SRM growth rate was 0.2 cm/year. Fourteen patients (32%) underwent either immediate (9 patients) or delayed intervention. Of 30 patients (68%) remaining on surveillance, none developed metastases.
Conclusions: Limited prospective data suggests that ESRD and immunosuppressed patients on AS for SRMs have similar short-term outcomes to those of immunocompetent controls with SRMs of the same size, suggesting promise for the safety of AS in renal transplant recipient candidates.
