SIU 2017: Neoadjuvant Targeted Therapy in the Treatment of Localized RCC

Lisbon, Portugal ( Targeted therapy (TT) significantly increases survival of patients with metastatic renal cell cancer (RCC), decreasing the size of the primary tumor as well. The objective of this study was to assess the efficacy of neoadjuvant TT on kidney tumor size with subsequent nephron-sparing surgery in the treatment of localized RCC.

During 2008-2016, 1,727 RCC patients aged 24 to 81 (mean 54.5) were operated in a single institution. Out of these, 51 patients received 2 months of neoadjuvant TT with Pazopanib (n=37) or Sunitinib (n = 14). Six (11%) patients had bilateral RCC, 4 (7.8%) patients had RCC in a solitary kidney, one patient (2.0%) had RCC in a horseshoe kidney, and the rest of the 40 patients (78.4%) had unilateral RCC. In general, 57 RCC tumors were clinically assessed. The size of the tumor ranged from 15 mm to 170 mm (mean 68.9 mm). The rate and extent of the tumor regression caused by neoadjuvant TT and the improvement in the setting of the organ-sparing surgery were analyzed.

The two-month TT course resulted in regression of tumor size in 51 (89.5%) tumors. In 4 (7.0%) - the tumor size was unchanged. In 2 (3.5%) patients, the tumor had actually increased in size by 10% and 15%, respectively. The overall average regression rate was (20.6 + 15.1%). When stratifying the regression in tumor size by the original size of tumor, the following regression rates were noted: 25.6% + 20.5% - in the group with tumors < 4 cm (n = 10); 17.3% + 12.1% - in the group with the tumor size 4 - 7 cm (n = 22); and 21.5% + 15% - in the group with tumors > 7 cm (n = 25), (p = 0.29). This reduction in tumor size resulted in partial nephrectomy being performed in 71.9% of patients. 

The authors concluded that neoadjuvant TT in localized RCC results in a mean tumor regression of 20.6% + 15.1%, facilitating organ-sparing treatment in 71.9% patients. Neoadjuvant TT needs to be further explored as a possible way to decrease tumor size and help facilitate performance of partial nephrectomy, rather than radical nephrectomy. 

Presented by: Oleg Voylenko
Affiliation: National Cancer Institute of Ukraine, Kyiv, Ukraine

Written by: Hanan Goldberg, MD, Urologic Oncology Fellow (SUO), University of Toronto, Princess Margaret Cancer Centre.Twitter: @GoldbergHanan at the 37th Congress of Société Internationale d’Urologie - October 19-22, 2017- Lisbon, Portugal