Clinical case 2

I'm not a clinician but from laboratory scientific point of view here are my comments for discussion.

It would be important to have at least some of the ovarian tissue assessed for histopathology together with any potenial immunohistochemical markers before making any recomemdation regarding transplantation. Although this is a limited sample assessment and can not guarantee the tissue transplantation would be free of malignancy, this should be undertaken for every patient thinking of having transplantation.

A site for transplantation where the tissue can be easily removed and monitored is important. Our teams experience with transplantation to an intrapertoneal abdominal site (Gook 2021) has shown this to be a suitable site for ovarian function and could be a possible site, if the case is recommended for transplantation.

The case does not specify whether the dysgerminoma was bilateral, requiring removal of both ovaries, or unilateral, with radical surgery performed as a precaution instead of a fertility-sparing approach. This point is important because it changes the risk that the frozen ovarian tissue might contain occult malignant lesions.

If the tumor was unilateral and this was confirmed by histology, then the frozen tissue from the contralateral ovary would be the safest to consider for transplantation. In this situation, the chance of hidden malignant cells is below 10%, similar to the risk of recurrence on the contralateral ovary in unilateral cases.

If, instead, the cryopreserved tissue came from the ovaries affected by the tumor, especially from areas close to the lesion, the risk of contamination could rise to 20–30%, similar to what is seen after cystectomy.

In that case, transplantation would carry significant safety concerns and should be done only after thorough testing of the frozen tissue with histological and molecular analyses after selecting specific oncological markers, and ideally xenotransplantation into immunocompromised mice to rule out residual disease.

Reference: Sessa C, Schneider DT, Planchamp F, et al. ESGO-SIOPE guidelines for the management of adolescents and young adults with non-epithelial ovarian cancers. Lancet Oncol. 2020;21(7):e360-e368.