New article published in the NEJM confirming the high risk for gastric cancer with susceptible folks with H. Pylori infections. Another reason for me to check dna platforms such as 23andme!
As a physician who not too long ago discovered my own asymptomatic H. pylori infection, I couldn’t help but wonder if there was more to the story than meets the eye. After all, we know H. pylori is a significant risk factor for gastric cancer, but what about our own genetic makeup and predisposition to the development of cancer? Are there hidden clues in our DNA that might make some of us more susceptible to this potentially deadly disease?
A recent study in the NEJM has made a groundbreaking discovery regarding the relationship between H. pylori infection, germline mutations, and gastric cancer risk. It turns out that, in addition to the well-known BRCA1 and BRCA2 genes, there are seven other genes (APC, ATM, CDH1, MLH1, MSH2, MSH6, and PALB2) that have been found to have pathogenic variants associated with gastric cancer risk. Interestingly, these genetic variants can cause different clinical and demographic characteristics among patients.
Now, here’s where it gets even more intriguing. The study found that the risk of gastric cancer is significantly increased in individuals who have both a germline pathogenic variant in a homologous-recombination gene and an H. pylori infection. In other words, there’s a sort of “double whammy” effect that makes these individuals particularly susceptible to gastric cancer with a cumulative lifetime risk approaching 45%!
https://www.nejm.org/doi/full/10.1056/NEJMoa2211807
Helicobacter pylori (H. pylori) infects the stomach lining and has been linked to an increased risk of gastric cancer just on its own. But it’s not just about the bacteria—our genes play a part too.So, why is this important? Well, understanding the specific genes involved in gastric cancer risk can help us identify individuals who may be at higher risk for developing the disease. This, in turn, could lead to better surveillance, earlier detection, and targeted treatments for these patients. Moreso, a heavier importance on the eradication of this bacteria in those who are most susceptible to the development of this deadly cancer!
Interestingly, the study found that the cumulative risk of gastric cancer for people with a pathogenic variant and without H. pylori infection was not very high (less than 5%). This suggests that eradicating H. pylori infection in people with a pathogenic variant could help reduce their risk of gastric cancer.
https://www.nejm.org/doi/full/10.1056/NEJMe2215503
Now, there are some limitations to this study. It’s retrospective, meaning the researchers looked back at existing data rather than conducting a prospective study. Also, they only looked at single-nucleotide variants and small insertions/deletions, so they may have missed some important genetic factors. And finally, the study focused on East Asian populations, so the results may not be entirely applicable to other populations.
But despite these limitations, this study gives us crucial insights into how our genes and the pesky H. pylori bacteria can gang up to increase the risk of gastric cancer. It also highlights the importance of screening for H. pylori infection in people who carry pathogenic variants in the identified genes. It’s clear that the dance between genes and bacteria is a complex one. As always, knowledge is power, and understanding these interactions can help us take the necessary steps to protect ourselves and our loved ones.
About the author
Dr. Sajeve Thomas is a distinguished medical professional and a compassionate guide in the field of oncology. With over a decade of dedicated experience as a board-certified medical oncologist/internal medicine specialist, Dr. Thomas has become a trusted expert in the treatment of melanoma, sarcoma, and gastrointestinal conditions. Currently practicing at the renowned Orlando Health Cancer Institute, he brings a wealth of expertise to the complex and challenging world of oncology.
Embrace the opportunity to engage with Dr. Sajeve’s expertise, and feel empowered to explore the vast expanse of oncology with renewed curiosity and understanding on “Ask MedOnCMD“