Predicting Response to Immunotherapy for Kidney Cancer With FDG-PET/CT
Posted: Thursday, May 23, 2019
According to research published in BMC Cancer, 18F-2-fluoro-2-deoxyglucose positron-emission tomography/computed tomography (FDG-PET/CT) may be effective in predicting the clinical response of patients with renal cell carcinoma who have undergone nivolumab treatment. However, the Japanese investigators cautioned that prospective studies are necessary to confirm these early findings in a larger group of patients.
The study included 9 patients with metastatic renal cell carcinoma who were treated with nivolumab from October 2018 to March 2017. All patients underwent baseline FDG-PET/CT, which was repeated after 1 month to evaluate a first response. A CT scan was performed at 4 months to assess a second response. Logistic regression analysis was used to determine the presence of any potential predictors, such as age and gender, lesion diameter, baseline maximum standardized uptake value (SUVmax), and site of metastasis.
A lesion was categorized as responding if it increased in diameter at least 30% between the first and second assessments. Of the 30 lesions in the study, 18 responded and 12 did not. Of all criteria included in the multivariate logistic regression analysis, just SUVmax elevation at 1 month was found to be an independent predictor (P = .025, odds ratio = 13.087).
“We compared change in diameter and SUVmax at first assessment with FDG-PET/CT, respectively,” noted Masahiro Yao, MD, PhD, of Yokohama City University in Japan, and colleagues. “All lesions with decreased diameter and elevated SUVmax at first assessment with FDG-PET/CT showed [response] at second assessment by CT scan, while most lesions with increased diameter and declined SUVmax at first assessment showed [nonresponse] at second assessment.”
Disclosure: The study authors reported no conflicts of interest.