Zucca LE, et al. - This trial incorporated an inquiry of the AXL expression in patients with metastatic renal cell carcinoma (mRCC) treated with sunitinib. This study also associated it with the patient's clinic-pathological features and therapeutic response. A link was illuminated between the AXL expression with worse clinical outcome. It possibly served as a pivotal prognostic biomarker in sunitinib-treated patients with metastatic renal cell carcinoma.

Methods

• This study recruited 64 patients with mRCC (51 clear cell carcinomas (CCCs) and 13 non-CCCs).
• Herein, the AXL expression was examined via immunohistochemistry in the primary tumor.

Results

• 47% (30/64) of the cases reported AXL positivity, namely in 43% (22/51) of CCCs and 61% (8/13) of non-CCC.
• The univariate analysis illustrated a statistical link between AXL expression with a poor prognosis, with a median overall survival of 13 months vs. 43 months in patients with negative AXL, taking into account just the clear cell subtype.
• In this subtype, along with the AXL positivity, other prognostic factors included absence of nephrectomy, Karnofsky performance status, more than 1 site of metastasis and liver metastasis.
• A connection was also brought to light between the AXL expression with shorter progression to sunitinib.
• The absence of nephrectomy (HR = 4.85, P = 0.001), more than 1 site of metastasis (HR = 2.99, P = 0.002), bone metastasis (HR = 2.95, P = 0.001), along with AXL expression (HR = 2.01, P = 0.048), served as independent poor prognostic factor in patients with mRCC.