The possible effects of the Japan Society of Clinical Oncology Clinical Practice Guidelines 2017 on the practice of fertility preservation in female cancer patients in Japan.

Purpose: In 2017, the first guidelines for fertility preservation in cancer patients were published in Japan. However, the impact of the guidelines remains unknown. Therefore, the authors conducted a nationwide survey on cryopreservation procedures in the period from shortly before to after publication of the guidelines (2016-2019) and compared the results with our previous survey (2011-2015). The authors also surveyed reproductive specialists' awareness of the guidelines and implementation problems. Methods: The authors sent a questionnaire to 618 assisted reproductive technology facilities certified by the Japanese Society of Obstetrics and Gynecology. Results: The authors received responses from 395 institutions (63.8%). Among them, 144 institutions conducted cryopreservation for cancer patients (vs. 126 in 2011-2015) and performed 2537 embryo or oocyte and 178 ovarian tissue cryopreservation procedures (vs. 1085 and 122, respectively). Compared with the previous period, indications were more varied and protocols for controlled ovarian stimulation were more standardized. Reproductive specialists' interest in oncofertility was high, but many reported three main difficulties: selecting a treatment method, storing samples in the long term, and securing the necessary human resources. Conclusions: The practice of fertility preservation in cancer patients in Japan has been considerably affected by the first Japanese guidelines.

A Japanese nationwide survey on the cryopreservation of embryos, oocytes and ovarian tissue for cancer patients.

AIM: The survival rates of cancer patients have greatly improved owing to the advances in oncology. The preservation of fertility in cancer patients is an important task. To determine the reality of cryopreservation of embryos, oocytes and ovarian tissue in cancer patients, large-scale survey analysis was performed in Japan. METHODS: We sent 613 Japan Society of Obstetrics and Gynecology-certified assisted reproductive technology institutions a questionnaire about their experience of performing cryopreservation for cancer patients between January 2011 and December 2015. Subsequently, the institutions that conducted cryopreservation for cancer patients were sent a second questionnaire. RESULTS: We received replies from 481 (78.5%) institutions. Among them, 126 (26.2%) conducted cryopreservation for cancer patients. These 126 institutions were sent a second questionnaire. Of these, 108 (85.7%) institutions responded. At the 108 institutions, 1085 embryo or oocyte cryopreservation procedures and 122 ovarian tissue cryopreservation procedures were conducted for cancer patients. Cryopreservation was mainly performed for breast cancer patients (~70%), followed by patients with hematological malignancy. A total of 361 and 19 embryo transfer cycles were performed for patients whose embryos and oocytes were cryopreserved, respectively, and 42 and seven institutions reported pregnancy outcomes after embryo transfer in patients that underwent embryo and oocyte cryopreservation, respectively. However, pregnancy was not observed in the seven cases that underwent ovarian tissue transfer. CONCLUSION: Indications, age limits and ovarian stimulation protocols for cryopreservation widely varied between the institutions. A national registration system for oncofertility must be established to evaluate the safety and efficacy of the current system.