Certain Targeted Therapies Tied to Improved Survival in Non–Clear Cell RCC

First-line VEGF tyrosine kinase inhibitors (TKIs), cytoreductive nephrectomy (CN), and metastasectomy improved survival in patients with metastatic non–clear cell renal cell carcinoma (RCC), according to recent study findings (Cancer Med. 2019 May 9. Epub ahead of print).

“The optimal treatment strategy for metastatic non-clear cell…[RCC] is still elusive and mainly extrapolated from evidence available for metastatic clear cell renal cell carcinoma,” said lead investigator Jung Kwon Kim, MD, Department of Urology, Seoul National University Bundang Hospital, Seongnam, Republic of Korea, and colleagues.

To assess survival outcomes and prognostic factors affecting survival in patients with metastatic non–clear cell RCC treated with targeted therapy, Dr Kim et al analyzed 156 (8.1%) patients with the disease from a cohort of 1922 patients in the Korean metastatic RCC registry.

Survival estimates for first-line progression-free survival (PFS), total PFS, and cancer-specific survival (CSS) were calculated via Kaplan-Meier curve analysis. In addition, prognostic factors for survival were assessed using multivariate Cox-proportional hazard regression analyses and comparisons were conducted with a log-rank test.

Patients with metastatic non–clear cell RCC had significantly lower survival outcomes with regard to first-line PFS, total PFS, and CSS (all P <.05) compared with patients with metastatic clear cell RCC.

Findings demonstrated survival benefits in recipients of first-line VEGF-TKIs (first-line PFS, and total PFS, all P <.05), CN (CSS, P <.0001), metastasectomy (CSS, P = .0017), and in patients with metachronous metastasis (first-line PFS, total PFS, and CSS, all P <.05).

Of note, the only significant predictive factor for first-line PFS and CSS was liver metastasis (all P <.05).

“In the current targeted therapy era, survival of…[metastatic non–clear cell RCC] is still inferior in comparison with that of…[metastatic clear cell RCC] patients,” Dr Kim and colleagues said.

“We found survival benefits in patients treated with first-line VEGF-TKIs/CN/metastasectomy, and metachronous metastasis patients,” they concluded.—Hina Khaliq