Causes of death of mutation carriers in Finnish Lynch syndrome families.

Lynch syndrome (LS) is an autosomal dominant cancer syndrome including increased life-long risk for colorectal (CRC) and endometrial (EC) cancer, but also for cancers of other types. The risk for CRC is up to 70-80 % and for EC up to 50-60 %. Due to screening and early diagnosing the mortality related to CRC and EC seems to be low. In spite of many studies on surveillance of mutation carriers, there is no comprehensive evaluation on causes of death in LS families. The disease history and cause of death of all the deceased, tested mutation carriers and their mutation negative relatives in the Finnish LS families (N = 179) was examined utilizing hospital records and relevant national registries. Out of 1069 mutation carriers 151 had succumbed; 97 (64 %) from cancer. Out of 1146 mutation-negative family 44 members had died; 11 (25 %) of them from cancer. In 12 (7.7 %) of the deceased mutation carriers no cancer had been diagnosed. The mean age of death from cancer was 63.2 years vs. 68.8 years from non-cancer causes. Only 7.9 % of the patients with CRC had died from CRC and 5 % of those with EC, respectively. 61 % of the cancer deaths were related to extra-colonic, extra-endometrial cancers. The cumulative overall and cancer specific death rates were significantly increased in Mut+ compared to Mut- family members. Even surveillance yields decrease in the life-long risk and mortality of the most common cancers CRC and EC in LS, almost all mutation carriers will contract with cancer, and two thirds of the deceased have died from cancer. This should be taken in account in genetic counseling. Mutation carriers should be encouraged to seek help for abnormal symptoms.