Reproduction post-chemotherapy in young cancer patients

Abstract

High-dose chemotherapy and radiotherapy has increased long-term survival of young patients with cancer. Sometimes however, the price paid is ovarian failure and sterility. It is highly important to detect who are the patients at risk in order to verify when fertility preservation is indicated. With conventional chemotherapy, there is significant differences in ovarian failure rate according to patients age, disease for which patients are treated for, and the drugs used. Bone marrow transplantation in cancer patients almost invariably induced ovarian failure, irrespective of patient age, treatment protocol or administration of hormonal treatment. Moreover, normal reproductive parameters post-chemotherapy does not necessarily imply that the ovaries escaped damage; ovarian injury is not an all or none phenomenon--partial loss of primordial follicle reserve can result in premature menopause as a delayed reaction to treatment. This should be taken into account while consulting former cancer patients about future planed pregnancies. The direct mechanisms of chemotherapy induced ovarian failure are poorly understood. An in vitro study has demonstrated that in the human ovary chemotherapy acts primarily on primordial follicles through induction of apoptotic changes in pregranulosa cells which lead to follicle loss. Protecting fertility potential in females exposed to chemotherapy with IVF and embryo cryopreservation or cryopreservation of ovarian tissue is practiced. Ovarian tissue cryopreservation: A recent study has demonstrated that laparoscopic ovarian biopsy performed with the round biopter is a safe and efficient method for collecting ovarian tissue for cryopreservation in cancer patients. In order to avoid possible hazards of transferring malignant cells, genetic and immunohistochemical markers for detection of minimal residual cancer cells in ovarian tissue are currently used. However, the reproductive potential of this method is still questionable. IVF: IVF and embryocryopreservation is currently used in infertile patients, however, several obstacles prevent it's wide implementation in cancer patients such as the need for male partner and the time needed for ovarian stimulation. A highly important issue is the possible risk of performing IVF and embryo cryopreservation to preserve fertility in females already exposed to chemotherapy. An animal study has raised serious concerns regarding the consequences of chemotherapy on future pregnancies. High abortion and malformation rates related to the different stages of oocyte maturation at the time of exposure to chemotherapy were demonstrated. These results should be taken into account when considering the use of IVF and embryo cryopreservation following chemotherapy treatment in cancer patients.