Shifting treatment patterns in chromophobe renal cell carcinoma: A U.S. real-world data analysis

Chromophobe renal cell carcinoma (chRCC) is the second most common variant histology RCC. There are no dedicated prospective studies in this subtype, and evidence supporting contemporary first-line therapies is limited to mixed-histology, single-arm trials. We leveraged real-world data to characterize evolving treatment patterns and associated outcomes in chRCC.

Patients with chRCC were retrospectively identified from the ConcertAI Patient360™ RCC Dataset, a US-based de-identified real-world dataset derived from electronic medical records, linked claims, and mortality data. Histology was defined by ICD-O-3 codes (8270/3, 8317/3) and NCI System code C40344. Among patients with metastatic disease treated with first-line systemic therapy, regimens were categorized as tyrosine kinase inhibitors (TKIs), immune checkpoint inhibitors (IO, monotherapy or IO/IO), MET inhibitors (METi), mTOR inhibitors (mTORi), or IO-based combinations (IO+TKI or IO+METi). Outcomes included real-world progression-free survival (rwPFS) and overall survival (rwOS), estimated using Kaplan–Meier methods.

A total of 87 patients with metastatic chRCC were identified. Median age at diagnosis was 62.5 years (IQR 52.3–72.8), and 59% were male. Most were treated in community oncology practices (93.1%) and were White (74.7%), with 8.1% Black and 5.8% Hispanic or Latino. At diagnosis, 25.3% had stage IV disease and 68.9% had ECOG 0–1. Among 51 patients with evaluable first-line treatment data, TKIs were most common (43%), followed by METi (15.6%) and IO-based combinations (15.6%). Use of IO and IO-based regimens increased over time. Median rwPFS and rwOS were 5.45 and 21.5 months, respectively. No consistent differences in survival were observed across treatment groups based on qualitative comparison of Kaplan–Meier curves.

In this national real-world cohort of metastatic chRCC, treatment has shifted toward IO and IO-based combinations, though survival outcomes remained comparable across regimens. Histology-focused prospective trials are needed to guide optimal therapy.