Lynch Syndrome
Lynch syndrome is a genetic condition which makes an individual more susceptible to certain types of cancers. Specifically, it has been thought to increase risk for developing colorectal or endometrial cancers.
But, a recent study discovered that microsatellite instability (MSI) as well as mismatch repair deficiency (MMR-D), used to determine lynch syndrome, are indicative of the syndrome across a much broader range of tumors than researchers first claimed. Previously, it was understood that MSI and MMR-D could predict colorectal cancer or endometrial cancer diagnoses. Now, it’s come to light that they could predict a much wider array of cancer diagnoses. In fact, the study showed that half of the patients with MSI tumors (high or intermediate) had a different cancer than colorectal or endometrial.
The study also indicated that about half of the participants who were diagnosed with Lynch syndrome had not previously met the criteria to receive genetic testing for the condition. That’s astounding. It’s clear we need to better understand what factors may indicate Lynch syndrome and further encourage testing for those individuals.
Luckily, this study should help us do that.
The Study
The study investigated over 15,000 patients who had over 50 different cancer diagnoses. Lynch syndrome was identified in about 16% of those with MSI-high status. For those with intermediate status, only about 2% had lynch syndrome and for those with mircosatellite stable tumors, less than .5% had Lynch syndrome. MSI-high tumors are clearly most indicative of Lynch syndrome. However, of those with MSI-high status and a lynch syndrome diagnosis, only 50% had a colorectal or endometrial tumor.
What’s the take away from this study? It indicates the necessity of investigating the presence of lynch syndrome for all MSI and MMR-D tumors regardless of the type of tumor or family history.
If we are able to better understand cancer risk, we are able to take more preventative measures. These may include providing testing for relatives, increased monitoring, or a risk-reducing surgery.
You can read more about this study and its findings here.
