Metastasis-free survival for metastatic tumors appears to be worse than previous research has suggested. Photo: Amy Bade, OD. Click image to enlarge.

To better understand the accuracy of predicted metastasis-free survival using a commercially available gene expression profiling test, researchers recently conducted a cohort study of uveal melanoma patients. They found that predicted metastasis-free survival appears to be too pessimistic when compared with their findings and other reported data.

Consecutive patients with uveal melanoma who underwent prognostic fine-needle aspiration biopsy at the time of primary treatment were included in this study. Researchers extracted the predicted metastasis-free survival from the gene expression profiling report. Observed metastasis-free survival was defined as the time to metastasis. To obtain overall data on metastasis-free survival, the study authors performed a meta-analysis of published reports.

The study included 347 patients from two institutions. The mean age of diagnosis was 59.4 years, and the median follow-up interval was 38 months. The researchers reported that the observed metastasis-free survival rates at three and five years for patients with Class 2 tumors in this cohort and in published studies were better than those predicted by gene expression profiling.

Among patients with Class 2 tumors, the data showed that those with metastasis had larger tumors vs. non-metastatic tumors. The study authors observed a significant association between larger tumor size and an increased hazard ratio of metastasis.

This analysis raises questions regarding the accuracy of survival prediction among patients with uveal melanoma, according to the study authors. In their paper on the study for JAMA Ophthalmology, they concluded, “These findings suggest the predicted metastasis-free survival for metastatic tumors (Class 2) appears to be worse than that observed here and reported by others. Incorporation of tumor size in the prediction model may enhance its accuracy. Adjuvant therapy trials may not be able to rely on predicted metastasis-free survival to calculate efficacy with a high degree of confidence.”

Singh AD, Binkley EM, Wrenn JM, et al. Predicted vs observed metastasis-free survival in individuals with uveal melanoma. JAMA Ophthalmol. July 21, 2022. [Epub ahead of print].