November is Stomach Cancer Awareness Month and it’s something that hits close to home for obvious reasons. Prior to learning about CDH1 and Hereditary Diffuse Gastric Cancer (HDGC), I knew very little about stomach cancer and definitely had no idea that there were people out there living without their stomachs and have been for a while. The goal of this blog is to share some facts about stomach cancer and if you’ve learned something, then I’ve done my job.
In Canada, the five year survival rate for stomach cancer is 25% (1). Stomach cancer is difficult to detect in it’s early stages as it rarely causes symptoms. According to the American Cancer Society, the signs and symptoms of stomach cancer can include (2):
- Poor appetite
- Weight loss (without trying)
- Abdominal (belly) pain
- Vague discomfort in the abdomen, usually above the navel
- A sense of fullness in the upper abdomen after eating a small meal
- Heartburn or indigestion
- Vomiting, with or without blood
- Swelling or fluid build-up in the abdomen
- Low red blood cell count (anemia)
When you read this list, you can see that some of the symptoms are common among the general population. How many people experience heartburn or indigestion out there? I know I experienced heart burn since high school that worsened and was especially bad the five years prior to having my total gastrectomy. I used to walk around with a constant supply of tums or other antacids. Was this the beginning of stomach cancer? Who knows. Often these symptoms can be attributed factors other than stomach cancer (i.e. stomach virus, ulcer, stress, etc).
HDGC attributes to less than 5% of stomach cancer (3). CDH1 is a tumor suppressant gene. Each person is born with two copies of the CDH1 gene which codes a protein called E-cadherin. This protein is responsible for cell signalling and cell to cell adhesions. When people are born with the CDH1 mutation, half of the team is already knocked out which puts all the responsibility on the remaining gene. Researchers aren’t sure what knocks out the other one, but when it is gone – we’re in trouble. This is why people with a CDH1 mutation or Hereditary Diffuse Gastric Cancer Syndrome are at a much higher risk for developing diffuse gastric cancer earlier in life. The average age is 38 (3) but people have passed away as early as teenagers.
I’ve linked this before but to those new joiners to my blog (Welcome!) here is the link again. I think Dr. Perry Guilford does a really great job of breaking down such a complex topic in a way that we can all understand. It’s from the No Stomach for Cancer’s Spotlight on Gastric Cancer event I attended back in April. Skip to 27:54 to learn about CDH1.
Genetic testing for the CDH1 mutation is available for families who fit the eligibility criteria. In Ontario the criteria is as follows (3):
- At least two relatives with diffuse-type gastric cancer
- At least one diagnosed under age 50 or families with at least three relatives with diffuse-type gastric cancer at any age
- Families with one case of very young diffuse-type gastric cancer (e.g. under age 35), or families with diffuse-type gastric cancer and lobular breast cancer may also be considered.
Genetic testing is a BIG decision and definitely not something to be done impulsively. For those who think they fit the criteria, please speak with a genetic counselor.
Thanks all for sticking with me on this blog post to the very end. I hope you all learned something and feel free to share!
- Canadian Cancer Statistics 2015 (2015, June). Retrieved from http://www.cancer.ca/~/media/cancer.ca/CW/cancer%20information/cancer%20101/Canadian%20cancer%20statistics/Canadian-Cancer-Statistics-2015-EN.pdf
- American Cancer Society (2015, March 16). Signs and Symptoms of Stomach Cancer. Retrieved from http://www.cancer.org/cancer/stomachcancer/detailedguide/stomach-cancer-signs-symptoms
- Mount Sinai Hospital Zane Cohen Centre. (n.d.) Hereditary Diffuse Gastric Cancer Syndrome – HDGC. Retrieved from http://www.zanecohencentre.com/gi-cancers/diseases/hdgc