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Published on: December 9, 2015
A validation of models for prediction of pathogenic variants in mismatch repair genes
Cathy Shyr1, Amanda L Blackford2, Theodore Huang1
1Department of Biostatistics, Harvard T.H. Chan School of Public Health, Boston, MA; Department of Data Science, Dana-Farber Cancer Institute, Boston, MA.
Purpose:
Models used to predict the probability of an individual having a pathogenic homozygous or heterozygous variant in a mismatch repair gene, such as MMRpro, are widely used. Recently, MMRpro was updated with new colorectal cancer penetrance estimates. The purpose of this study was to evaluate the predictive performance of MMRpro and other models for individuals with a family history of colorectal cancer.
Methods:
We performed a validation study of 4 models, Leiden, MMRpredict, PREMM5, and MMRpro, using 784 members of clinic-based families from the United States. Predicted probabilities were compared with germline testing results and evaluated for discrimination, calibration, and predictive accuracy. We analyzed several strategies to combine models and improve predictive performance.
Results:
MMRpro with additional tumor information (MMRpro+) and PREMM5 outperformed the other models in discrimination and predictive accuracy. MMRpro+ was the best calibrated with an observed to expected ratio of 0.98 (95% CI = 0.89-1.08). The combination models showed improvement over PREMM5 and performed similar to MMRpro+.
Conclusion:
MMRpro+ and PREMM5 performed well in predicting the probability of having a pathogenic homozygous or heterozygous variant in a mismatch repair gene. They serve as useful clinical decision tools for identifying individuals who would benefit greatly from screening and prevention strategies.
Insights
MMRpro+ and PREMM5 models effectively predict pathogenic variants in mismatch repair genes. These tools aid in identifying individuals who could benefit from enhanced cancer screening and prevention strategies.
Area of Science:
- Genetics
- Oncology
- Bioinformatics
Background:
- Predictive models like MMRpro are crucial for identifying individuals at risk of pathogenic variants in mismatch repair (MMR) genes.
- Recent updates to MMRpro incorporated new colorectal cancer (CRC) penetrance estimates, necessitating re-evaluation of its performance.
Purpose of the Study:
- To evaluate the predictive performance of MMRpro and other models in individuals with a family history of colorectal cancer.
- To compare the accuracy, calibration, and discrimination of various predictive models for MMR gene variants.
Main Methods:
- A validation study was conducted on 784 members of US clinic-based families.
- Four models (Leiden, MMRpredict, PREMM5, and MMRpro) were assessed against germline testing results.
- Model combination strategies were analyzed to potentially improve predictive performance.
Main Results:
- MMRpro with additional tumor information (MMRpro+) and PREMM5 demonstrated superior discrimination and predictive accuracy compared to other models.
- MMRpro+ exhibited the best calibration, with an observed to expected ratio of 0.98 (95% CI = 0.89-1.08).
- Combined models showed improved performance over PREMM5 and were comparable to MMRpro+.
Conclusions:
- MMRpro+ and PREMM5 are effective tools for predicting pathogenic variants in MMR genes.
- These models can assist clinicians in identifying individuals who would benefit from targeted screening and prevention strategies for hereditary cancer syndromes.
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