Patients with kidney cancer that has spread to the brain are living longer than patients treated in earlier eras, according to a large international study led by researchers at Duke. The study also identifies factors that can help physicians estimate prognosis and introduces an updated tool for assessing survival in the modern era of cancer treatment.
The findings, published in The Lancet Oncology, are based on 1,049 patients with newly diagnosed renal cell carcinoma with brain metastases treated between 2016 and 2022 at academic medical centers.
Median overall survival was 20 months, compared with 9.6 months among patients treated from 1985 to 2007 and 12 months among those treated from 2006 to 2015.
“Survival for these patients has improved overall, but we also found that survival varies widely and that the prognostic factors that help us estimate survival have changed. These factors have been incorporated into the updated prognostic index, the Renal Graded Prognostic Assessment, or Renal GPA, a tool that helps patients and their doctors decide when aggressive treatment is and is not appropriate. The Renal GPA can also be used to stratify clinical trials to ensure those trials are comparing similar patients,” said Paul W. Sperduto, MD, MPP, FASTRO, lead author of the study.
The Renal GPA can be used to estimate survival for patients, and researchers identified four factors significantly associated with survival: functional status, measured by the Karnofsky Performance Status; blood levels of albumin, a protein found in plasma; the number of brain metastases; and whether cancer had also spread outside the brain.
The updated Renal GPA divides patients into prognostic groups. Median survival ranged from 4.8 months for patients with the lowest scores to 51.2 months for those with the highest scores.
The researchers say these findings could help inform future clinical trials. Patients with brain metastases have historically been excluded from many studies of systemic cancer therapies, despite the longer survival now seen among some patients. Outcomes from the study suggest it is no longer necessary to indiscriminately exclude patients with brain metastases from clinical trials of systemic therapies, which will expand clinical trial eligibility, increase accrual and speed discovery.
“Patients with brain metastases from renal cell cancer are an important – and growing – segment of the population, and it is essential that they have access to the clinical trials that will shape future therapies, improving control of their systemic disease and brain metastases while improving both the length and quality of their lives,” said John Kirkpatrick, MD, PhD, a professor of radiation oncology at Duke and one of the authors of the study.
The study included 50 authors from 21 academic institutions in the United States, Canada and Japan. Patient data were uniformly curated across participating institutions and housed in a Duke University database using Research Electronic Data Capture (REDCap).
The researchers emphasize that the study was retrospective and observational and was not designed to determine whether one treatment was better than another.
This study was funded by the US National Institutes of Health (NCI P30CA014236) and the Duke Center for Brain and Spine Metastases.