Recent improvements in genetic and genomic medicine have increased the chance of diagnosing hereditary breast and ovarian cancer (HBOC). We conducted an internet survey of 248 medical institutions in Japan with the aim of understanding the clinical management after HBOC diagnosis. Among 131 institutions that agreed to participate, 127 performed BRCA1/2 genetic testing and 107 undertook surveillance. Retention of BRCA1/2 pathological variants and the development of related cancers influenced the implementation of surveillance. The most frequently performed surveillance approaches were breast mammogram, breast ultrasound, transvaginal ultrasound, and ovarian tumor marker measurement. Some institutions performed male breast cancer screening, prostate specific antigen measurement, and pancreatic cancer screening. Genetic counseling was provided during follow-up at 59 institutions, but this was irregular at many. Issues in HBOC follow-up included internal and external medical collaborations, securing corresponding human resources, and financial support for patients.

　Women with a BRCA pathogenic variant are required to manage the risk of breast and ovarian cancer. Decision-making of the optimal strategy (e.g., prophylactic surgery, chemoprevention, or surveillance) is very complex and difficult due to uncertain effects and impact. This study aimed to develop a decision aid for women with a BRCA pathogenic variant and evaluate its acceptability. The International Patient Decision Aids Standards were used as a guide for an evidence-based development process. We created a prototype using the Ottawa Decision Support framework. During its development, we conducted required assessment from six experts. Once completed, its acceptability was assessed via semi-structured interviews, which included open-ended feedback, with 27 women with a BRCA pathogenic variant. All the participants felt the decision aid would have been helpful during their consultation and recommended it for future patients. However, many participants indicated the need for further information regarding the various symptoms after risk-reducing salpingo-oophorectomy and the cost of each medical strategy. Acceptability of the decision aid was high. Furthermore, based on the evaluation, it was further revised to meet the needs.

　A patient with tuberous sclerosis complex, who had an enlarged polycystic liver and lymphangioleiomyomatosis, required surgical treatment for endometrial cancer. When tuberous sclerosis complex is accompanied by a severely enlarged polycystic liver and renal angiomyolipoma, the possibility of PKD1/TSC2 contiguous gene syndrome must be considered. In this case, to forestall complications, a radical surgery had to be carefully planned in consideration of the liver and kidney conditions, ongoing dialysis, lymphangioleiomyomatosis, and multiple aneurysms, among other conditions. Strategies for the management of endometrial cancer can include surgery, radiation, cytotoxic agents, and hormonal therapy. In this case, we believe that the most appropriate post-surgical approach was the use of molecular biology therapy.

　An 8-month-old Japanese boy had been found at the 7-month health checkup to have poor weight gain and developmental delay. Bilateral retinoblastoma was diagnosed owing to bilateral intraocular neoplastic lesions found with magnetic resonance imaging and funduscopy. Chromosome examination revealed deletion of 46, XY, del (13) (q14q22), and the fluorescence in situ hybridization revealed deletion of region 13q14 of the RB transcriptional corepressor 1 gene (RB1)． Furthermore, the multiplex ligation-dependent probe amplification identified total deletion of exons 1 to 27 of RB1. These results led to the diagnosis of 13q deletion syndrome associated with retinoblastoma. In such cases, retinoblastoma must be treated and multifocal support, such as an early rehabilitation program against developmental delay, follow-up for future development of secondary cancer, and genetic counseling for the parents, should be suggested.

　A patient with stage IV ovarian cancer, who was a BRCA gene variant carrier and 9 years after breast cancer treatment, requested risk-reducing mastectomy (RRM). The patient had bone metastasis, but her disease was stable with PTX/CBDCA followed by PARP inhibitor, and we approved the treatment at a joint conference. Although RRM reduces the risk of developing breast cancer, there are many cautious opinions about its indication due to the poor prognosis of ovarian cancer. However, with the advent of PARP inhibitors, the prognosis of ovarian cancer has markedly improved in recent years, and it has become necessary to provide medical care commensurate with this improvement. RRM can be performed concurrently with ongoing treatment of ovarian cancer. It is necessary to judge the progression-free status and to propose RRM at an appropriate time.

　Since the treatment of hereditary breast and ovarian cancer and the cancer genome medical system were approved in Japan, cancer genomics has become part of the clinical setting. However, as Fukui Prefectural Hospital prioritizes public health medicine, it has not been able to spare enough human resources to begin a cancer genomics program until recently. To solve this problem, the genomic doctor and nurse and other member of staff have been elected from each department related to cancer genomics. Nurses and medical record managers play a more important role than initially expected. The implementation of our system offers insights that would be helpful to other hospitals. Herein, we report details of the system of genomic doctors, our history up to launching the department, and several problems we encountered.