Applicability of adult techniques for ovarian preservation to childhood cancer patients

International Society of Paediatric Surgical Oncology (IPSO) Surgical Practice Guidelines

Most children with tumors will require one or more surgical interventions as part of the care and treatment, including making a diagnosis, obtaining adequate venous access, performing a surgical resection for solid tumors (with staging and reconstruction), performing procedures for cancer prevention and its late effects, and managing complications of treatment; all with the goal of improving survival and quality of life. It is important for surgeons to adhere to sound pediatric surgical oncology principles, as they are closely associated with improved local control and survival. Unfortunately, there is a significant disparity in survival rates in low and middle income countries, when compared to those from high income countries. The International Society of Paediatric Surgical Oncology (IPSO) is the leading organization that deals with pediatric surgical oncology worldwide. This organization allows experts in the field from around the globe to gather and address the surgical needs of children with cancer. IPSO has been invited to contribute surgical guidance as part of the World Health Organization Initiative for Childhood Cancer. One of our goals is to provide surgical guidance for different scenarios, including those experienced in High- (HICs) and Low- and Middle-Income Countries (LMICs). With this in mind, the following guidelines have been developed by authors from both HICs and LMICs. These have been further validated by experts with the aim of providing evidence-based information for surgeons who care for children with cancer. We hope that this initiative will benefit children worldwide in the best way possible. Simone Abib, IPSO President Justin T Gerstle, IPSO Education Committee Chair Chan Hon Chui, IPSO Secretary.

Is the pre-antral ovarian follicle the 'holy grail'for female fertility preservation?

Fertility preservation is not only a concern for humans with compromised fertility after cancer treatment. The preservation of genetic material from endangered animal species or animals with important genetic traits will also greatly benefit from the development of alternative fertility preservation strategies. In humans, embryo cryopreservation and mature-oocyte cryopreservation are currently the only approved methods for fertility preservation. Ovarian tissue cryopreservation is specifically indicated for prepubertal girls and women whose cancer treatment cannot be postponed. The cryopreservation of pre-antral follicles (PAFs) is a safer alternative for cancer patients who are at risk of the reintroduction of malignant cells. As PAFs account for the vast majority of follicles in the ovarian cortex, they represent an untapped potential, which could be cultivated for reproduction, preservation, or research purposes. Vitrification is being used more and more as it seems to yield better results compared to slow freezing, although protocols still need to be optimized for each specific cell type and species. Several methods can be used to assess follicle quality, ranging from simple viability stains to more complex xenografting procedures. In vitro development of PAFs to the pre-ovulatory stage has not yet been achieved in humans and larger animals. However, in vitro culture systems for PAFs are under development and are expected to become available in the near future. This review will focus on recent developments in (human) fertility preservation strategies, which are often accomplished by the use of in vitro animal models due to ethical considerations and the scarcity of human research material.

Effects of vitrification on the viability of alginate encapsulated isolated bovine pre-antral follicles

PURPOSE

Individual follicle cryopreservation techniques, without hydrogel support, are labor-intensive and a substantial proportion of isolated follicles are lost during handling and after warming. Therefore, the viability and morphology of isolated bovine (as a model for human) pre-antral follicles after vitrification and warming, when encapsulated in alginate beads, were investigated.

METHODS

Bovine pre-antral follicles were mechanically isolated and divided into four different groups: (1) culture in 2% alginate beads (3D system) and vitrification in beads using mesh cups (3DVIT), (2) culture in 2% alginate beads (3DCUL), (3) culture in 96-well plates (2D system) and vitrification using High Security Vitrification straws® (2DVIT), (4) culture in a 2D system (2DCUL). The same vitrification and warming protocols were used for embedded (3DVIT) and non-embedded follicles (2DVIT).

RESULTS

No differences were observed in follicle viability between group 2DCUL and 3DCUL. Group 3DVIT showed the lowest viability (45.9%) according to calcein and neutral red staining among all groups. Group 2DVIT displayed the highest viability (87.5%) and largest percentage of follicles with a well-preserved morphology.

CONCLUSIONS

Our results show that, using a vitification protocol optimized for non-embedded follicles, 2D culture is more effective in vitrifying isolated follicles. However, embedding in alginate allow to handle follicles more efficiently, i.e., without excessive manipulation and thus less labor-intensive in combination with a reduced loss of follicles during the procedure. Based on the increased work efficiency, but lower viability and higher proportion of follicles showing impaired morphology, we consider it advantageous to optimize the protocol for the vitrification of embedded follicles to increase survival and maintain morphology after vitrification.

Effects of L-carnitine on follicular survival and graft function following autotransplantation of cryopreserved-thawed ovarian tissues

The aim of this study was to investigate the effects of L-carnitine (LC) on follicular survival and ovarian function following cryopreservation-thawing and autotransplantation of ovarian tissues. ICR mice were divided into three groups: control; saline group (cryopreservation+autograft+saline); and LC group (cryopreservation+autograft+L-carnitine). The ovarian tissues from control group, saline group, and LC group were histological assessed. There were no significant differences in the percentage of morphologically normal primordial follicles between the LC group and the saline group. After 28 days of autotransplantation, apoptosis rates, plasma malondialdehyde (MDA), progesterone (P4) and estradiol (E2) concentrations, and follicular densities of grafts were evaluated. Apoptosis rate and the concentration of MDA in the LC group were significantly lower than those in the saline group. The concentration of E2 and follicular densities of grafts in LC group were significantly higher than that in saline group. LC inhibits follicle apoptosis and increases follicular survival and function of ovarian graft.

Fertility Preservation for Prepubertal Girls: Update and Current Challenges

With increasing rates of diagnosis of childhood cancers and the evolution of more effective treatment options resulting in prolonged life spans, fertility preservation counseling is an integral component of the discussion at the time of diagnosis of childhood cancers. The primary fertility preservation option that exists for prepubertal girls is ovarian tissue cryopreservation. Although ovarian tissue cryopreservation is still considered to be experimental in nature, live births have resulted from orthotopic tissue transplantation. Fertility preservation should be offered to all prepubertal girls at high-risk for premature ovarian failure as a result of gonadotoxic treatment. Ethical and legal questions surrounding these issues must be considered as more and more pediatric patients pursue fertility preservation.

Fertility preservation for patients with cancer: American Society of Clinical Oncology clinical practice guideline update

PURPOSE

To update guidance for health care providers about fertility preservation for adults and children with cancer.

METHODS

A systematic review of the literature published from March 2006 through January 2013 was completed using MEDLINE and the Cochrane Collaboration Library. An Update Panel reviewed the evidence and updated the recommendation language.

RESULTS

There were 222 new publications that met inclusion criteria. A majority were observational studies, cohort studies, and case series or reports, with few randomized clinical trials. After review of the new evidence, the Update Panel concluded that no major, substantive revisions to the 2006 American Society of Clinical Oncology recommendations were warranted, but clarifications were added.

RECOMMENDATIONS

As part of education and informed consent before cancer therapy, health care providers (including medical oncologists, radiation oncologists, gynecologic oncologists, urologists, hematologists, pediatric oncologists, and surgeons) should address the possibility of infertility with patients treated during their reproductive years (or with parents or guardians of children) and be prepared to discuss fertility preservation options and/or to refer all potential patients to appropriate reproductive specialists. Although patients may be focused initially on their cancer diagnosis, the Update Panel encourages providers to advise patients regarding potential threats to fertility as early as possible in the treatment process so as to allow for the widest array of options for fertility preservation. The discussion should be documented. Sperm and embryo cryopreservation as well as oocyte cryopreservation are considered standard practice and are widely available. Other fertility preservation methods should be considered investigational and should be performed by providers with the necessary expertise.

Legal termination of a pregnancy resulting from transplanted cryopreserved ovarian tissue due to cancer recurrence

PURPOSE

To report on a woman who conceived naturally and had a normal intrauterine pregnancy following transplantation of frozen/thawed ovarian tissue but decided to have an early abortion due to recurrence of breast cancer.

METHODS

The patient was diagnosed breast cancer and received antineoplastic treatment that forced her into premature ovarian insufficiency and infertility. Ovarian tissue cryopreserved prior to chemotherapy was transplanted following cancer treatment restoring fertility and regular menstrual cycles.

RESULTS

The patient conceived 6 month after transplantation. However, she experienced recurrence of breast cancer and decided on legal termination of the pregnancy in the first trimester.

DISCUSSION

The obtained pregnancy only 6 month following transplantation underlines the ability of the procedure. The recurrence occurred near the original site of the tumor and was most unlikely related to the transplantation. The activity of the transplanted tissue is likely to be destroyed by the renewed antineoplastic treatment she will receive. However, she still has the majority of one ovary cryostored and may later want to undergo additional transplantation to regain fertility or to have menstrual cycles back.

Optimizing cryoprotectant perfusion conditions for intact ovary: a bovine model

PURPOSE

The aim of this study was to detect the effects of different perfusion pressure and different length of perfusion period on whole ovarian cryopreservation

METHODS

Bovine whole ovaries were vitrified-warmed. The ovaries were divided into the experimental groups according to different perfusion pressure and different length of perfusion period. Follicular viability was assessed using the trypan blue test; the percentage of morphologically normal primordial follicles and the 17-β estradiol level in the culture supernatants were measured.

RESULTS

When perfusion pressure was 100 mmHg, and the length of perfusion period was 40 min, the viability of ovarian tissues in bovine whole ovarian cryopreservation were higher than other protocols.

CONCLUSION

Protocol IIb (the perfusion pressure was 100 mmHg, and the length of perfusion period was 40 min) was appropriate for bovine whole ovarian cryopreservation.