Spermatogenesis after gonadotoxic childhood treatment: follow-up of 12 patients.

STUDY QUESTION

What is the long-term impact of presumed gonadotoxic treatment during childhood on the patient's testicular function at adulthood?

SUMMARY ANSWER

Although most patients showed low testicular volumes and some degree of reproductive hormone disruption 12.3 (2.3-21.0) years after gonadotoxic childhood therapy, active spermatogenesis was demonstrated in the semen sample of 8 out of the 12 patients.

WHAT IS KNOWN ALREADY

In recent decades, experimental testicular tissue banking programmes have been set up to safeguard the future fertility of young boys requiring chemo- and/or radiotherapy with significant gonadotoxicity. Although the risk of azoospermia following such therapies is estimated to be high, only limited long-term data are available on the reproductive potential at adulthood.

STUDY DESIGN SIZE DURATION

This single-centre prospective cohort study was conducted between September 2020 and February 2023 and involved 12 adult patients.

PARTICIPANTS/MATERIALS SETTING METHODS: This study was carried out in a tertiary care centre and included 12 young adults (18.1-28.3 years old) who had been offered testicular tissue banking prior to gonadotoxic treatment during childhood. All patients had a consultation and physical examination with a fertility specialist, a scrotal ultrasound to measure the testicular volumes and evaluate the testicular parenchyma, a blood test for assessment of reproductive hormones, and a semen analysis.

MAIN RESULTS AND THE ROLE OF CHANCE

Testicular tissue was banked prior to the gonadotoxic treatment for 10 out of the 12 included patients. Testicular volumes were low for 9 patients, and 10 patients showed some degree of reproductive hormone disruption. Remarkably, ongoing spermatogenesis was demonstrated in 8 patients at a median 12.3 (range 2.3-21.0) years post-treatment.

LIMITATIONS REASONS FOR CAUTION

This study had a limited sample size, making additional research with a larger study population necessary to verify these preliminary findings.

WIDER IMPLICATIONS OF THE FINDINGS

These findings highlight the need for multicentric research with a larger study population to establish universal inclusion criteria for immature testicular tissue banking.

STUDY FUNDING/COMPETING INTERESTS: This study was conducted with financial support from the Research Programme of the Research Foundation-Flanders (G010918N), Kom Op Tegen Kanker, and Scientific Fund Willy Gepts (WFWG19-03). The authors declare no competing interests.

TRIAL REGISTRATION NUMBER

NCT04202094; https://clinicaltrials.gov/ct2/show/NCT04202094?id=NCT04202094&draw=2&rank=1 This study was registered on 6 December 2019, and the first patient was enrolled on 8 September 2020.