Real world data on treatment of chromophobe renal cell carcinoma.

Abstract

409 Background: Chromophobe renal cell carcinoma (ChRCC) is the third most common subtype of renal cell carcinoma (RCC), accounting for 5%–7% of all RCCs. ChRCCs are generally viewed to have a favorable clinical outcome compared to clear cell RCC, yet up to 10% of patients with ChRCC will develop metastases. To date, there are no genomic biomarkers that predict post-surgical metastatic recurrence, and no standard of care exists for treating metastatic chRCC. We sought to better understand real world patient experiences in this underrepresented and understudied patient population. Methods: The survey was developed by the Kidney Cancer Research Alliance (KCCure) and was broadcast between 07/2022 and 09/2022 to patients via website, mailing lists and social media platforms. Those who agreed to participate were surveyed for demographics (age, gender, race, income, country) and clinical characteristics (date of the diagnosis, disease stage, treatment history). Out of 1,062 participants 121 patients self-identified with chRCC, 34 patients had metastatic disease, and 23 patients had received systemic therapy. Results: The majority of patients were from the United States (75%), median age was 49.7 years (range 19-74), 70 percent of patients identified as female, and 30 percent of patients identified as male. Stage distribution at initial diagnosis was stage 1 in 37.3%, 27.3% were stage 2 and stage 3 respectively, 8.3% were metastatic at diagnosis. 14% of patients reported having sarcomatoid dedifferentiation. 20 percent of patients (24) experienced recurrent metastatic disease after a median duration of 3.3 years (range 1-6). Of the 23 patients who received treatment, first line therapy consisted of TKI monotherapy (9), combination IO and TKI (7), combination IO/IO (4), mTOR mono-therapy (1), other therapies (2). Second and later line therapies were combination IO/IO (3), IO and TKI (9), Lenvatinib and everolimus (7), TKI monotherapy (5), mTOR monotherapy (5) and other therapies (5). Median duration of therapy was 43 months (range 2-196). The most used TKIs were cabozantinib and lenvatinib. In the metastatic setting, 4 patients reported being treated as part of a clinical trial, 9 patients reported that no one had ever talked to them about participating in a clinical trial. 6 patients said that no trials were being held at their treating center. Conclusions: Patients reported higher rates of recurrence than what is usually reported in ChRCC, however this could reflect sample bias as patients with more aggressive disease may be more likely to engage with patient communities. No standardized treatment for metastatic disease could be identified. Overall treatment duration was comparable to clear cell carcinoma. Very few patients had access to clinical trials. ChRCC-specific clinical trials and tailored treatment regimens are urgently needed.