Epidemiological, Clinical, Molecular Features and Early Detection Strategy of Most Frequent Hereditary Cancers in Latvia

The aim of the study was to determine epidemiological, clinical and molecular features of hereditary breast-ovarian, colorectal, endometrial, prostate and pancreatic cancer in Latvia. The study was performed from 2006 to 2009. Family cancer histories and DNA samples from 5,040 cancer cases were collected, and more than 6,000 molecular tests were performed including multiplex PCR, direct sequencing, denaturing high performance liquid chromatography and others. For the first time, a BRCA2 gene mutation positive hereditary breast cancer family was identified. The necessity of 2 BRCA1 gene founder mutations testing, irrespective of family cancer history for breast and ovarian cancer patients, was confirmed on a large number of positive cases. Regarding hereditary ovarian cancer, every ninth case affected with this malignancy was associated with the BRCA1 gene mutation. For the first time, positive familial adenomatous polyposis cases positive for APC gene mutation were reported and data on the clinical frequency of hereditary endometrial and prostate cancer were provided. In pancreatic cancer patients there was a 3.5% frequency of BRCA1 gene founder mutations.