The preservation of childrenʼs oncofertility program “Snowflake”. First results

Background. Antitumor therapy using various different classes chemotherapy drugs in childhood has a negative impact on prepubertal and pubertal gonads. One of the groups dealing with the problems of pediatric oncofertility was the St. Petersburg Group for the Preservation of Oncofertility in Children with Cancer. The primary goal of the “Snowflake” program (N.N. Petrov National Medical Research Center of Oncology, leader A.P. Karitsky) is to preserve fertility in patients under 17 years old with tumors, the end point is the creation of a cryobank of biological material.

The purpose of the work is to present the first results of targeted recruitment of patients to the “Snowflake” program, as well as to analyze the speed of this recruitment.

Materials and methods. The N.N. Petrov National Medical Research Center of Oncology initiated clinical study protocols for preserving fertility in prepubescent and puberty girls and boys. The planned number of study participants is 125 people. The recruitment forecast is 5 patients per month, or 60 patients per year.

Results. During the program, 28 primary children aged one to 17 years were screened for the risk of developing gonadotoxicity after anticancer treatment. Fourteen patients did not meet the inclusion criterias, 14 children were included in the final report. The reasons for exclusion were low risk of gonadotoxicity (n = 9), refusal of invasive intervention (n = 5), genetic paternity was not a priority for the family of one boy. In 6 cases, germ cell tumors were diagnosed, 3 cases were patients with soft tissue sarcomas and 2 were patients with lymphomas, one each with osteosarcoma, Wilms tumor and medulloblastoma. Cryopreservation of ovarian tissue was performed for 6 girls, testicular tissue for 4 boys, 4 more teenagers performed sperm extraction using masturbation. There was no delay in initiating anticancer treatment in either case.

Conclusions. Further studies of gonadotoxicity are needed as the number of survivors with childhood cancer will increase in the coming years.

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