(RxWiki News) Genetic testing is opening doors in the helping people understand the potential health issues they may face in the near and distant future.
Those individuals unfortunate enough to have inherited Lynch syndrome, a genetic condition that predisposes patients to develop colon cancer and certain female cancers, should have genetic testing to determine which specific gene mutation they have to understand and anticipate their health issues as they age.
Patients with Lynch syndrome have one of three types of gene mutations associated with the syndrome: MSH2, MLH1 or MSH6. A new study from France assigns an age and chance of occurrence associated with each gene mutation and colon cancer, endometrial cancer and ovarian cancer.
"Lynch syndrome patients should discuss with their doctor having a preventive hysterectomy."
Study leader Valerie Bonadona, M.D., Ph.D., of the Centre National de la Recherche Scientifique, Villeurbanne, France reports that their findings contribute to the ongoing discussion involving preventive gynecological care. A woman with Lynch syndrome should consider having a preventive hysterectomy.
Dr. Bonadona adds that the findings of this study helps in identifying the target population for this surgery and defines the optimum age the surgery should occur.
The study analyzed 537 families with Lynch syndrome and provides age-specific risks as well as gene-specific risks for each type tumor. These results clarify the phenotypic differences between MSH2, MLH1, or MSH6 mutation carriers and show the clinical significance of the risk of gynecological cancers, especially ovarian cancer.
The researchers found significant differences in cumulative cancer risk between the 3 different mutated genes. Colorectal estimated cumulative risk by the age of 70 was 41 percent in MLH1 mutation, 48 percent for MSH2 and 12 percent in MSH6.
The estimated cumulative risks in carriers started to increase at the 30 years of age regardless of which gene mutation was involved. Endometrial cancer had an estimated cumulative risk by age 70 years of 54 percent for MLH1, 21 percent for MSH2, and 16 percent for MSH6. At 40 years of age, the estimated cumulative risk did not exceed 2 percent, regardless of which gene mutation was involved.
When considering ovarian cancer, the estimated cumulative risks by age 70 years were 20 percent for MLHl, 24 percent for MSH2, and 1 percent for MSH6. At 40 years of age, the estimated cumulative risk did not exceed 1 percent, irrespective of gene mutation.
This study is published in the June 8 issue of the Journal of the American Medical Association.
