In contrast to most other solid tumours, renal masses were not commonly biopsied to achieve histopathological analysis before treatment. As a consequence, benign renal masses were often overtreated.
Our study sought to challenge this paradigm by assessing the safety, diagnostic accuracy, and clinical significance of RTB in patients with SRMs. The study included 195 patients with SRM, who underwent RTB and were followed for a median of 42 months.
We demonstrated that in SRMs, percutaneous RTB was a safe diagnostic method that provided valuable histopathological information. The results of RTB reduced overtreatment in 34% of the patients. Our findings are consistent with other comprehensive studies, such as the systematic review by Marconi et al., which reported high sensitivity and specificity for RTB. In our cohort, we achieved a sensitivity of 95% and specificity of 100%, with a complication rate of 1%.
Our study also addressed the challenge of inconclusive RTB and found that conducting a re-biopsy following an inconclusive initial biopsy significantly increased the diagnostic yield, in that the re-biopsies were diagnostic in 82% of cases. These observations may provide guidance to clinicians in the management of patients with inconclusive RTB results.
Renal oncocytomas diagnosed with RTB, are a clinical challenge due to an infrequent finding of hybrid oncocytic tumors that may contain chromophobe renal cell carcinoma, which may share histopathological features with oncocytoma. Among 44 patients in our study diagnosed with oncocytoma via RTB, 6 underwent re-biopsy and 3 underwent surgery. The final histology reaffirmed the initial diagnosis of oncocytoma in all these cases. In total, 41 patients with oncocytoma were treated non-surgically. None of these patients developed malignancy or metastasis during the follow-up. This suggests that RTB, despite the diagnostic challenges, remains reliable in identifying renal oncocytoma in the clinical setting.
From health-economics perspective, the ability of RTB to accurately distinguish between benign and malignant tumours can result in significant cost savings by reducing unnecessary surgeries and associated hospitalization. Avoiding unnecessary treatment of benign tumours promotes the efficient use of healthcare resources, and reduces the risks of complications and patient morbidity.
Our results underline the importance of incorporating RTB into the diagnostic pathway as a step towards a more individualized patient treatment. We encourage further research and dialogue regarding the evolving role of RTB in the management of small renal masses.
Written by:
- Bassam Mazin Hashim, Department of Urology, Region Västmanland - Uppsala University, Center for Clinical Research, Västmanland Hospital Västerås, Västerås, Sweden
- Börje Ljungberg, Department of Diagnostics and Intervention, Urology and Andrology, Umeå University, Umeå, Sweden