AUA 2018: Controversies in Urology: Kidney Cancer – Treatment with Thermal Ablation – PRO

San Francisco, CA (UroToday.com) Jaime Landman, MD gave a presentation advocating for the use of thermal ablation for small renal masses (SRM). SRM is a CT driven dilemma. Over the years, CT usage has risen exponentially. The usage of CT scans has jumped from 1995 to 2016 by 30-fold. Approximately 30% of renal masses are less than 3 cm, with the highest incidence among people aged 75-85.

When biopsying SRMs, 25% are benign while the rest are malignant. Out of the malignant masses, about 40% are high grade malignancy, with the rest being low grade malignancy or indolent malignancy. Therefore, almost 30% of SRMs<3cm are with high grade malignancy and 70% are benign or with low grade malignancy (Figure 1).

Figure 1 – 3 cm mass renal biopsy outcomes:
cm mass renal biopsy outcomes


When assessing treatment outcomes of SRMs, we need to examine oncologic outcomes, renal function, complications, and whether the therapeutic modality is truly minimally invasive. When looking at oncologic outcomes (metastasis free survival) of clinical stage T1a, no difference was seen between partial nephrectomy (PN) and cryotherapy, although a small difference was seen between PN and radiofrequency ablation (RFA). A study by Pierorazio [1] compared cancer specific survival (CSS), metastasis free survival (MFS) and recurrence free survival (RFS) between PN and ablative techniques, showing small differences in favor of PN (Table 1).

Table 1 – Oncologic outcomes of SRM treatment:
Oncologic outcomes of SRM treatment

Thermal ablation has a clear advantage with regards to a significantly lower % change in renal parenchymal volume compared to PN. Additionally, the % of complications is significantly lower with ablative techniques, compared to PN (Table 2). In the end, ablative modalities reach all the goals of treatment including oncologic outcomes, preservation of renal function, minimum complications and being minimally invasive.

Table 2 – Complications:
Complications

In conclusion, according to Landman, SRM biopsy needs to be done to match the standards of all other surgical specialties. We need to move to a disease specific standard of care. Lastly, we need to embrace disease specific treatment strategies and thoughtful application of minimally invasive modalities like percutaneous ablation. 


Presented by: Jaime Landman, MD Irvine, California

References:
1. Pierorazio P, et al. J Urol 2016 May; 195(4)

Written by:  Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre @GoldbergHanan at the 2018 AUA Annual Meeting - May 18 - 21, 2018 – San Francisco, CA USA

Read the Succeeding Presentation: 
Controversies in Urology: Kidney Cancer – Treatment with Thermal Ablation – PRO Rebuttal
Read the Opposing Argument:
Controversies in Urology: Kidney Cancer – Treatment with Thermal Ablation – CON
Read the Opposing Argument Rebuttal:
Controversies in Urology: Kidney Cancer – Treatment with Thermal Ablation – CON Rebuttal