In what was termed as SA’s first oncofertility session, chaired by Dr Chris Venter of Vitalab, three international experts in the field presented their findings at the recent SASREG congress.
“When patients are given the devastating news of cancer, they may be focused on cancer and unable to think about fertility or the possibility of having a future family. The primary goal of oncofertility is to increase awareness and access to patients who have been diagnosed with cancer to fertility preservation counselling, and to inform them of their fertility preservation options,” said Dr Chris Venter.
“Getting our oncology colleagues together with us in partnership is what’s important. There is no doubt we are at the earliest phase of understanding this unmet need, and to identify both existing and bring new technologies as solutions,” said Dr Teresa Woodruff, an American medical researcher, renowned in the field of human reproduction and oncology.
Advances in cancer diagnostics and therapeutics have increased the number of young cancer survivors. However, some life-preserving cancer treatments can pose a threat to a patient’s fertility Collaborations between biomaterials scientists, reproductive endocrinologists, and clinical researchers have led to breakthroughs that may improve and expand fertility preservation options for women.
Cooperation with the social sciences, humanities, law and education allows a comprehensive means of understanding and fulfilling the needs of patients wishing to preserve fertility after a cancer diagnosis.
At the moment, fertility options for women with cancer include embryo or egg banks, adoption, surrogacy, natural pregnancy, ovarian cryopreservation or tissue transplant and tissue cryopreservation. “Scientific goals require us to ask hard questions. There are legal concerns, religious constraints, ethical discussions, historical context and transgenerational hope,” said Dr Woorduff.
Oocyte cryopreservation and vitrification (an ultrarapid freezing process that prevents ice crystal formation) technologies have greatly improved. Despite the number of live births, however, oocyte cryopreservation technology remains inefficient and is still considered investigational. Ideally, advances in cancer care and reproductive technologies should have converged and provided fertility options to young cancer patients’ years ago.
Dr Michael Grynberg from France reiterated that there are many unknowns in this emerging field. In cancer patients, Dr Grynberg emphasised that we don’t have the luxury of time, in terms of the number of cycles to retrieve eggs, with limited possibilities of pregnancy for IVF. And there is no restitution of ovarian function.
Surgery in these patients should be approached with caution. If is often overwhelming for a patient who has just received a cancer diagnosis to have to undergo surgery so close to starting chemotherapy. There is also a possibility of reintroducing malignant cells. The patient’s choice is extremely important regarding the advantages and drawbacks of oocyte versus ovarian tissue cryopreservation.
This makes it difficult for doctors to recommend one technique over the other. He expressed that the term ‘fertility preservation’ should be used with caution. Dr Nao Suzuki, Obstetrics and Gynaecology at St Marianna University, Japan, presented on laparoscopic approach to ovarian tissue collection and retransplantation. He looked at the indications and risks associated with this procedure.
SUCCESSFUL BIRTHS IN WOMEN TRANSPLANTED WITH FROZEN-THAWED OVARIAN TISSUE
Since 2004, when the first pregnancy after reimplantation in an orthotopic site (a site in the pelvic cavity) was reported, the number of live births has reached more than 130 worldwide, showing a logarithmic increase during the past two years and highlighting the need to move from experimental studies to widespread clinical application.
Because reports of the live births baby achievement occurred successfully all over the world, the ovarian tissue cryopreservation was not a technique of the research stage anymore. Vitrification of human ovarian tissue has excellent survival of ovarian stroma and blood vessels. It is a fast method with no particular technical instruments needed.
It is clinically feasible and shows excellent survival in tissue culture. One must bear in mind that there are no live births reported so far. The procedure requires thorough training. Concentrations and osmolarities as well as speed of the procedure are of extremely high importance. A toxic influence on the tissue is possible in less trained practitioners. In terms of transplantation techniques, it is still controversial which site the ovarian tissue should be transplanted to. Denmark prefers the ovary, while others choose the pelvic wall.
“We have started an international multicentre controlled study in which tissue is transplanted to sites, the ovary and the pelvic wall. Outcome criteria is the number of follicles on each site developed 3-12 months after transplantation,” he said.
According to Dr Woodruff, the vision for oncofertility 2029 is:
- Better cancer control and treatment
- Higher selectivity of patients
- Neo-adjunct fertoprotectives
- In-vitro follicle maturation
- Designer ovarian bioprosthetics
- Eventually, eliminate the field
Her take-home message was: “When grants and papers meet clinical problems, patient needs are met and can change a devastating diagnosis into life-affirming interventions.”