Hereditary Breast and Ovarian Cancer (HBOC) Syndrome

International guidelines for HBOC typically divided the recommendations into 2 categories: for women with and without a personal history of cancer. All members elected to streamline the guidelines into a single category using the family as a unit and modify the wordings to include salient aspects of both personal and family histories. Most of the guidelines (NICE, Canadian Saskatchewan, USPTF, ASCO, ESMO) were similar in recommending that women with young breast cancer, multiple family members with breast cancers, bilateral breast cancers, breast and ovarian cancers, male breast cancers, and multiple other related cancers (pancreatic, prostate, etc.) be included. In concordance with these recommendations, one local study showed that the highest risk group is families with breast and ovarian cancer.1

After reviewing the 7 sets of international guidelines, the committee decided to adopt the guidelines by the European Society for Medical Oncology (ESMO) Guidelines Working Group (2011) as the backbone guidelines2, as they were most encompassing, recommending 4 broad categories of patients to be referred: family history of breast or ovarian cancer, young onset cancer, male breast cancer, and multiple tumours. The Workgroup built upon these general guidelines and added specific information to make the guidelines easy for referring physicians to follow. Of note, the age threshold for young onset cancer was specified to be less than 40, while family history of breast or ovarian cancer was further divided into family history of breast and ovarian cancer and family history of 2 or more breast cancers, with at least one diagnosed below age 50 (adopted from the 2014 NCCN guidelines). In addition, members added a special note for clinicians to ask for a family history of young onset pancreatic and prostate cancer (diagnosed below age 50) in patients and/or families with breast cancer, and to consider referring these patients/families to a cancer genetics clinic for further evaluation (adopted from the 2014 NCCNguidelines). Recognizing that patients with certain histological subtypes of breast and ovarian cancer have up to 10-20% chance of carrying a BRCA1/2mutation, patients with triple negative breast cancer diagnosed below age 50 (adopted from the 2014 NCCN guidelines with age threshold added to increase the specificity for referral)3and patients with epithelial ovarian cancer diagnosed at any age (adopted from the 2012 ASCO guidelines), in particular those with high grade serous ovarian cancer4, were included in the referral criteria for HBOC.

The concept of population based screening forBRCA1/2has been proposed recently.5However, given the high test cost that has to be borne by the patients as well as our currently limited medical resources to handle pre- and post-test genetic counselling and test interpretations required from large-scale genetic testing, all members of the workgroup agreed not to include universal screening for hereditary breast and ovarian cancer syndrome in the guidelines, recognizing that genetic testing administered without appropriate counselling may result in misinterpretation and harm.6