Late Effects of Cancer Therapies on Gonadal Function, Fertility, Efficiency of Fertility Preservation Procedures and Pregnancy Outcomes

In the past two decades, evidence-based knowledge on the prevalence and risk factors for fertility impairment, including infertility, following cancer and numerous cancer treatment regimens has significantly increased. However, data remains mostly insufficient for individualized prediction of (future) fertility potential, including success of artificial reproductive technologies (ART). Furthermore, therapies have become increasingly complex. Recent treatment regimens have continuously implemented novel treatment approaches (e.g. immune therapies such as checkpoint inhibitors) for which no comprehensive data regarding its impact on fertility and pregnancy outcomes is available, yet.

It is crucial to carefully balance risk-benefit between fertility preservation (FP) procedures and potential of gonadal function/fertility impairment, to examine the efficiency and safety, as well as to assess patients' satisfaction regarding the FP procedures. Answering these questions is highly relevant as it has been shown that fertility capacity and post-treatment gonadal function may represent a significant part of the quality of life in young cancer survivors.

The study therefore aim to set up a large-scale network structure of emerging data collection programmes to evaluate the gonadotoxic risks, including the prevalence and course of ovarian/testicular dysfunction and/or fertility impairment and premature ovarian insufficiency/oligo/azoospermia following specific treatments, identification of further risk factors and predictive markers to enhance precision survivorship research in this field. Additionally, data on the use of fertility preservation/fertility treatment and patients' satisfaction related to these procedures in Europe shall be analysed to support patient-centric care.

Reproductive health counselling should not be restricted to evaluating the individual risk of gonadotoxicty and offering fertility preservation to those at risk. It also includes the sexual health, the use of post-cancer treatment contraception for those recommended to delay attempting pregnancy after a cancer diagnosis and the identification of potential obstetrical and neonatal risks to provide individualized, risk-adapted follow-up during pregnancy. An increased risk of obstetrical and neonatal complications has been reported for several conditions, including preterm delivery, pre-eclampsia, cardiac dysfunction, and gestational diabetes. Most available studies are based on population registry and lack of detailed information on critical factors such as the impact of the timing of pregnancy, method of conception or the type of cancer treatment received (e.g pelvic irradiation, anthracycline, targeted therapy, immunotherapy…), all of which may influence the outcomes.

The main objectives of this retrospective analysis of European ongoing adolescent and young adult (AYA) cancer patient cohorts are:

• To establish harmonized databases with clinical data on pre- and post-cancer therapy and reproductive outcomes in AYA patients followed longitudinally.

• To evaluate the impact of cancer treatment on long-term fertility according to cancer type and individual patients' characteristics (pre- and post-treatment) in male and female AYA populations.

• To evaluate effect of cancer therapies on ovarian function in female AYA patients

• To evaluate long-term effect on the endocrine function of the testis in male AYA patients i.e., the frequency of hypogonadism.

• To evaluate the obstetrical and neonatal outcomes according to the disease and treatment.