Changes in the overall survival of patients with metastatic renal cell carcinoma in the era of immune-checkpoint inhibitors

Background: The advent of immune checkpoint inhibitors (ICI) has brought about a significant transformation in the treatment of immunogenic tumors. On November 23, 2015, the United States Food and Drug Administration approved Nivolumab to treat metastatic renal cell carcinoma (RCC). We aimed to assess potential changes in the survival rates of patients with metastatic RCC at a population level after the approval of Nivolumab.

Methods: We used data from the latest version of the Surveillance, Epidemiology, and End Results (SEER) database which encompasses data up to the year 2020. We included patients with age ≥ 20 years who were diagnosed with 'distant' RCC from 2011 through 2020. Based on the approval of Nivolumab, the period from 2011 to 2020 was further grouped into 2011-2015 (pre-ICI era) and 2016-2020 (ICI era).

Results: The median overall survival (OS) was 8 months in the pre-ICI era compared to 11 months in the ICI era (log-rank test, χ2 = 102.53, p < 0.001). Patients diagnosed with metastatic RCC in the ICI era had a significantly lower risk of dying [Cox proportional Hazard Ratio of 0.77, 95 % CI (0.74-0.80)] compared to patients diagnosed in the pre-ICI era. Additionally, patients under the age of 75 had a lower risk of death compared to those aged 75 years or older. Patients who received chemotherapy (systemic therapy), radiotherapy, or surgery faced a significantly lower risk of mortality. Individuals with metastasis to the brain, bone, liver, or lung had a significantly higher risk of death than those without metastasis to these locations. Marital status also played a role, as married individuals had a significantly lower risk of death compared to those who were divorced, separated, or widowed at the time of diagnosis. Furthermore, income level influenced survival, with patients earning a median annual household income of more than USD 75,000 exhibiting a significantly lower risk of mortality compared to those earning between USD 50,000 and USD 74,000. There was no significant difference in survival observed between non-Hispanic blacks and non-Hispanic whites.

Conclusion: The advent of immune checkpoint inhibitors has led to a substantial improvement in the median overall survival of individuals diagnosed with metastatic renal cell carcinoma.