Opportunities to improve upon identification of patients at risk for hereditary cancer predisposition include revising BRCA1/2 and Lynch syndrome testing criteria to include additional clinically actionable genes with overlapping phenotypes and relaxing testing criteria for associated cancers.
We used the Centers for Disease Control and Prevention (CDC) Science Impact Framework to trace the impact of public health activities and partnerships on the implementation of the 2009 Evaluation of Genomic Applications in Practice and Prevention (EGAPP) Lynch Syndrome screening recommendation and the 2005 and 2013 United States Preventive Services Task Force (USPSTF) BRCA1 and BRCA2 testing recommendations.The EGAPP and USPSTF recommendations have each been cited by >300 peer-reviewed publications.
Following the identification in a proband of a germline BRCA1/BRCA2 mutation in hereditary breast-ovarian cancer (HBOC) or a DNA mismatch repair gene mutation in Lynch syndrome (LS) he or she will be asked to inform at-risk family members about the option for presymptomatic DNA testing.
Lynch syndrome and BRCA-1 and BRCA-2-associated hereditary breast and ovarian cancer are hereditary cancer syndromes frequently involving the gynaecological tract but tumours associated with similar molecular alterations may also occur sporadically.
Several studies have addressed the resultant increased demand for testing for Lynch syndrome and BRCA1/2 mutations in endometrial and ovarian cancers, respectively.
These findings substantiate the utility of multi-gene panel testing in ovarian cancer care regardless of age at diagnosis, family history, or histologic subtype, providing evidence for testing beyond BRCA1/2 and the Lynch syndrome genes.
A total of 413 cases were included in the study: 27 with Lynch syndrome (LS), 222 with germline BRCA 1 or 2 mutations and 164 cases with strong family or personal history (non-Lynch/non-BRCA).
Women with familial cancer syndromes such as hereditary breast and ovarian cancer syndrome (BRCA1 and BRCA2) and Lynch syndrome are at a significantly increased risk of developing ovarian cancer and are advised to undergo prophylactic removal of their ovaries and fallopian tubes at age 35 to 40 years, after childbearing is complete.
We present 2 cases of OCS; one arising in a patient with a pathogenetic BRCA1 mutation and the other in a woman affected by Lynch Syndrome (LS) carrying a MSH6 germline mutation.
The cancer risks associated with mutations in moderate-penetrance genes are lower and different than those reported for high-penetrance gene mutations (such as mutations in BRCA1 and BRCA2, and those associated with Lynch syndrome).
Risk assessment and early detection strategies in individuals with BRCA1/2 mutations and with Lynch syndrome have been quite extensively studied, whereas much less is known about the management of mutation carriers with less common high-penetrance cancer susceptibility genes (PTEN, TP53, STK11, CDH1), and particularly those who carry mutations in moderate-penetrance genes (e.g., PALB2, CHEK2, ATM, NF1, RAD51C, RAD51D, BRIP1).
This brief article will provide a summary of these advances over three eras of cancer genetics: pre-discovery of the more common high impact genes, namely BRCA1/BRCA2 and the mismatch repair genes associated with Lynch syndrome; the time during which the genes were being discovered; and current day.
Fifteen individuals had mutations in BRCA1 or BRCA2; 93% of these met the NCCN criteria for Lynch syndrome testing and 33% met NCCN criteria for BRCA1 and BRCA2 analysis (P = .0017).
Among 1046 study participants, 40 BRCA1/2-negative patients (3.8%; 95% CI, 2.8%-5.2%) harbored deleterious mutations, most commonly in moderate-risk breast and ovarian cancer genes (CHEK2, ATM, and PALB2) and Lynch syndrome genes.
Participants who underwent BRCA1/2 or Lynch syndrome genetic testing (n = 77; 2.42% of respondents) were more likely to be female and to have a family or personal history of cancer than those not undergoing testing.
Germline mutations in BRCA1 and BRCA2 genes predispose to hereditary breast cancer, whereas carriers of mutations in any of the mismatch repair genes (MMR; hMLH1, hMSH2, hMSH6, hPMS2) are highly susceptible to Lynch syndrome.
Nine of 102 (8.8%) families were regarded as having hereditary breast-ovarian cancer syndrome, two families (2.0%) were diagnosed with Lynch syndrome and six patients harbored BRCA1 or BRCA2 mutations.
The microarray consisted of probes corresponding to the exons and flanking introns of BRCA1 and BRCA2 (≈1,700) and Lynch syndrome/polyposis genes MLH1, MSH2, MSH6, APC, MUTYH, and EPCAM (≈2,200).
Within this group, germline mutations in mismatch repair (MMR) genes, known otherwise as Lynch syndrome (LS), account for the majority of cases that are not associated with mutations in BRCA1 or BRCA2.
In addition to this syndrome, gastric cancer risk is elevated in Lynch syndrome associated with germline mutations in DNA mismatch repair genes and microsatellite instability, in hereditary breast and ovarian cancer syndrome due to germline BRCA1 and BRCA2 mutations, in familial adenomatous polyposis caused by germline APC mutations, in Li-Fraumeni syndrome due to germline p53 mutations, in Peutz-Jeghers syndrome associated with germline STK11 mutations, and in juvenile polyposis syndrome associated with germline mutations in the SMAD4 and BMPR1A genes.