Methylation of Gene Panel Strong Indication of Breast Cancer Survival Outcomes
A high cumulative methylation index is linked to shorter median progression-free disease and overall survival.
HealthDay News -- According to a study published in the Journal of Clinical Oncology, methylation of a gene panel is a strong predictor of survival outcomes in metastatic breast cancer (MBC).
Kala Visvanathan, MBBS, from the Johns Hopkins University School of Medicine in Baltimore, and colleagues used a new quantitative multiplex assay to predict survival outcomes in MBC.
There were 10 genes that were tested in duplicate serum samples at baseline, week 4, and first re-staging for 141 women.
On the basis of 6 of the 10 genes, a cumulative methylation index (CMI) was generated, and correlations with progression-free survival (PFS), overall survival (OS) and disease status at first re-staging were assessed.
The researchers found that women with a high CMI had shorter median PFS and OS (2.1 and 12.3 months, respectively), compared with a low CMI (5.8 and 21.7 months, respectively). Among women with MBC, a high versus low CMI at week 4 independently correlated with worse PFS and OS (hazard ratios, 1.79 and 1.75, respectively) in multivariable models.
A CMI increase from baseline to week four correlated with worse PFS and progressive disease at first re-staging (both P<.001). Even in the presence of circulating tumor cells, week 4 CMI was a strong predictor of PFS (P=.004).
"Methylation of this gene panel is a strong predictor of survival outcomes in MBC and may have clinical usefulness in risk stratification and disease monitoring," the authors write.
Several authors disclosed financial ties to the biopharmaceutical industry. Several authors are named on patents relating to methylation and cancer.
Visvanathan K, et al. Monitoring of Serum DNA Methylation as an Early Independent Marker of Response and Survival in Metastatic Breast Cancer: TBCRC 005 Prospective Biomarker Study. Journal of Clinical Oncology. November 21, 2016. doi: 10.1200/JCO.2015.66.2080. [Epub ahead of print]