Hereditary Diffuse Gastric Cancer: British Columbia Cancer Agency Research Update June 2009

Current Research Projects of the Hereditary Diffuse Gastric Cancer Research Team at the British Columbia Cancer Agency.

Over the last 10 years, we have learnt a lot about hereditary diffuse gastric cancer (HDGC). However, there are still many critical knowledge deficits which need to be addressed to improve the cancer control of families with known CDH1 mutations and to inform the care of families with strong histories of gastric cancer of whom known mutations have been identified.

Our research team is both collaborating with other members of the International Gastric Cancer Linkage Consortium (IGCLC) to develop a more accurate understanding of the cancer risks associated with carrying CDH1 mutations, and is performing research locally that should help our global research community move forward.

Studies we are actively engaged in include:

  1. The identification of gastric cancer associated mutations in families who do not have the traditional CDH1 mutations.  In these studies, we are looking for a mutation outside of the coding region of the CDH1 gene and using novel technologies to identify regions in other genes.
  2. The role of CDH1 in hereditary breast cancer. In this large study which is nearly completed, Dr. Intan Schrader, a geneticist in training working with our team, has studied CDH1 in almost 400 families with a history of lobular breast cancer. So far it appears that CDH1 mutations are rare in families which have breast cancer but no history of gastric cancer. The results of this study will help to form testing guidelines for women with lobular breast cancer and a family history of breast and/or stomach cancer.
  3. Quality of life post-prophylactic gastrectomy. Pardeep Kaurah, the genetic counselor who has worked with most of the families we have tested in British Columbia, is now completing her PhD studies. The project she has selected is the study of the quality of the life post-prophylactic gastrectomy. We hope that through this work we will obtain a better sense of the pertinent clinical and pychosocial information that should be provided to individuals who are considering prophylactic gastrectomy. These would include any indicators that could be used to predict who would fare poorly after this procedure. Until we have a more effective screening tool for hereditary diffuse gastric cancer, prophylactic gastrectomy would appear to be a useful cancer-risk reduction strategy.  Therefore studying the consequences of this procedure is relevant.

Through these studies, our international collaborations and our ongoing interaction with HDGC families, we will continue to formulate new questions to be answered and endeavor to contribute new knowledge that will help in the management of individuals who carry CDH1 mutations.

By David Huntsman, Pardeep Kaurah