An article published recently in the Journal of Medical Genetics outlines new recommendations for management of patients and families with Hereditary Diffuse Gastric Cancer, based on a workshop of the International Gastric Cancer Linkage Consortium (IGCLC) held in late 2008.
The workshop, convened in Cambridge, UK, included expert geneticists, gastroenterologists, oncologists, surgeons, and pathologists from nine countries, and discussion topics included genetic counselling and testing, surveillance endoscopy, prophylactic gastrectomy, and review of pathology specimens.
Some of the outcomes of the IGCLC workshop include:
- Updated risk for diffuse gastric cancer to 80% by age 80 in both males and females with a CDH1 mutation
- Updated risk for lobular breast cancer to 60% by age 80 in affected females
- Broadened criteria for genetic testing for HDGC, to include the following:
- Diffuse gastric cancer (DGC) in one individual under the age 40 without a family history
- 2 cases of gastric cancer in the family, one of which was confirmed DGC before age 50
- 3 confirmed cases of DGC in first or second degree relatives independent of age
- Personal or family history of DGC and lobular breast cancer, with one diagnosed before age 50
- Updated guidelines for endoscopic and breast surveillance, as well as recommendations for colonoscopy in patients with a family history of colon cancer
- Prophylactic gastrectomy advised for all patients with a diagnosed CDH1 gene mutation, however the timing of gastrectomy is debatable and is discussed in detail in the article
- Development of a protocol for pathology review of gastrectomy specimen in HDGC patients
Finally, it was decided that HDGC ‘Centres of Excellence’ be determined in different geographic regions, so that information and research results from HDGC patients and families around the world can be managed and discussed by experts in the field.
Read the full article from the Journal of Medical Genetics.
Personal comment from Karen Chelcun Schreiber:
Even with the broadened criteria for genetic testing for HDGC, my family still would not have met the published testing criteria when the second family member, my brother Greg, had Stage IV cancer which began with stomach symptoms. We pursued genetic counseling and testing on our own, following the eventual confirmation that Greg’s primary cancer was indeed diffuse gastric cancer. I raised my particular concern about this with Parry Guilford, one of the contributors to this article.Parry further explained as follows:
Keep in mind that guidelines are an aid or resource for clinicians, not a fixed protocol. There will always be a grey zone. For example, the guidelines are inherently biased against small families, or against people who don’t know their wider family history. There is no suggestion that if a family doesn’t meet the guidelines they won’t have a particular mutation – it just means they are less likely to do so. Smaller groups (referring to families like mine) may not meet the formal criteria, they are still suggestive of a CDH1 mutation. – Parry Guilford
My personal position, based upon my own family’s experience, is that if anyone is seeing any instances of diffuse gastric cancer, lobular breast cancer, or a combination of the two in their family, regardless of the age or number of family members, they should seek genetic counseling. I would also add colon cancer to that mix. A simple blood test saved at least three lives in my family, perhaps more.