Systemic Therapy in Patients With Metastatic Xp11.2 Translocation Renal Cell Carcinoma

Xp11.2 translocation renal cell carcinoma (Xp11.2 tRCC) is a unique subtype with poor prognosis, its response to systemic therapy is not fully understood, we evaluated the benefit of systemic therapy in these patients.

Between May 2006 and December 2019, patients diagnosed with Xp11.2 tRCC from Peking university cancer hospital were collected. The Kaplan-Meier method was used to estimate progression-free survival (PFS) and overall survival (OS) distributions.

Metastatic Xp11.2 tRCC was found in 45 patients. The median PFS and median OS was 7.4 months (4.5-8.8) and 17.9 months (12.4-24.4), respectively. First-line treatment mainly included sunitinib (n = 14), sorafenib (n = 15), axitinib (n = 6), and pazopanib (n = 5), and the median PFS of these regimens were 7.4 months, 5.4 months, 9.4 months, 8.9 months, respectively. Two patients who received Vascular endothelial growth factor receptor - tyrosine kinase inhibitor (VEGFR-TKI) plus immune checkpoint inhibitor (ICI) as first line therapy had a PFS of more than 16.6 months and more than 25.6 months, respectively. Twenty-four patients received subsequent therapies, which included VEGFR-TKI/ICI, VEGFR-TKI and mTOR inhibitor. The ORR and median PFS was 33% and 7.1 months, 7.7% and 4.3 months, 0% and 2.1 months for these treatments, respectively. The estimated median OS was 17.3 months (95% CI, 11.2 to not reached) in patients with TKI/ICI treatment and 11.0 months (95% CI, 6.1 to not reached) without TKI/ICI treatment in subsequent therapies (P = .04). Patients with serous cavity effusion or IMDC poor risk groups had significantly shorter median PFS and median OS.

Metastatic Xp11.2 tRCC is an aggressive disease. VEGFR-TKI agents appeared to demonstrate some efficacy, VEGFR-TKI /ICI combination might be a useful tool for the treatment of metastatic Xp11.2 tRCC.