Key clinical point: AXL expression is associated with worse clinical outcome and may be an important prognostic biomarker in sunitinib-treated patients with metastatic renal cell carcinoma.
Major finding: AXL positivity was observed in 47% (30/64) of cases, namely in 43% (22/51) of clear cell carcinomas and 61% (8/13) of non-clear cell carcinomas. Considering only the clear cell subtype, the univariate analysis showed that AXL expression was statistically associated with a poor prognosis, with a median overall survival of 13 months vs. 43 months in patients with negative AXL. In this subtype, along with the AXL positivity, other prognostic factors were absence of nephrectomy, Karnofsky performance status, more than 1 site of metastasis and liver metastasis. 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), together with AXL expression (HR = 2.01, P = 0.048) were independent poor prognostic factor in patients with mRCC.
Study details: 64 patients with metastatic renal cell carcinomas (51 clear cell carcinomas and 13 non-clear cell carcinomas) were evaluated for AXL expression by immunohistochemistry in the primary tumor.
Disclosures: The authors had no relevant financial disclosures.
Zucca L E et al. Urologic Oncology: Seminars and Original Investigations 2018: 36; 11.e13-11.e21