Location of bone metastasis may affect outcomes in metastatic renal cell carcinoma

MIAMI — Patients with metastatic renal cell carcinoma who had vertebral metastasis achieved significantly shorter survival than patients who had nonvertebral metastasis, according to results of a small study presented at International Kidney Cancer Symposium.

The finding suggests location of bone metastasis may affect clinical outcomes in this patient population, according to Diego Abreu, MD, of the department of urology at Hospital Pasteur in Montevideo, Uruguay, and colleagues concluded.

Approximately 30% of patients with metastatic renal cell carcinoma have bone metastases, which are associated with considerable morbidity, a high likelihood of skeletal complications and poor prognosis. Five percent of patients with metastatic disease have exclusively bone metastasis at diagnosis, according to study background.

Abreu and colleagues assessed the effect of bone metastasis location on clinical outcomes among a cohort of patients with metastatic renal cell carcinoma included in the Latin American Renal Cancer Group, a consortium of 45 centers in Uruguay, Brazil, Argentina, Mexico, Peru, Chile, Bolivia and Spain.

Researchers collected data on clinicopathological characteristics, 24-month survival, OS, and sites of exclusively bone metastasis at diagnosis.

The analysis included 56 patients (median age, 59.5 years; range, 40-85; 64.3% men), of whom 23 had vertebral metastasis and 33 did not. The most common bone metastasis locations included spine (23.2%), lower limbs (14.3%), thorax plus limbs (8.9%), pelvic (8.9%), upper limbs (8.9%), spine plus thorax (7.1%), and thorax alone (7.1%).

Most patients had ECOG performance status of 0 or 1 (80%), stage pN0 disease (86.2%) and clear cell histology (85.7%).

More than two-thirds (68.6%) of patients received prior systemic therapy with anti-VEGF/mTOR inhibitors. One patient received prior systemic therapy with cytokines, and 15 patients (29.4%) received no prior systemic therapy.

In the entire cohort, researchers reported OS rates of 79% at 1 year, 62% at 2 years and 35% at 5 years.

Analysis by bone metastasis location showed significantly lower 2-year OS (50% vs. 87%; HR = 2.7; P = .029) and 2-year cancer-specific survival (47% vs. 87%; HR = 3.25; P = .011) among patients with vertebral metastasis. Both survival trends persisted through 60 months of follow-up. – by Mark Leiser

For more information:

Abreu D, et al. The impact of bone metastasis location in the clinical outcomes of patients with metastatic renal cell carcinoma (mRCC): An analysis from the Latin American Renal Cancer Group (LARCG). Presented at: International Kidney Cancer Symposium; Nov. 3-4, 2017; Miami.

Disclosure: The authors report no relevant financial disclosures.