Assessment of measurable residual disease in ovarian tissue collected for fertility preservation in patients in remission from acute myeloid leukaemia: A pilot study.

Allogeneic haematopoietic stem cell transplantation (ASCT) is a curative treatment for acute myeloid leukaemia (AML) but carries a high risk of gonadotoxicity. Ovarian tissue cryopreservation (OTC) offers a fertility preservation option, yet its safety in AML remains uncertain due to the risk of leukaemic cell reintroduction. The FERTILAM pilot study evaluated measurable residual disease (MRD) in ovarian tissue collected at complete remission (CR) from nine AML patients undergoing OTC before ASCT. MRD was assessed using patient-specific clonal markers via droplet digital polymerase chain reaction on DNA and RNA from bone marrow (BM), ovarian cortex and medulla. At CR, MRD-DNA was detected in ovarian cortex of four of nine patients, all with concurrent MRD positivity in BM. Three patients were negative in both BM and ovarian tissue. Paired cortex/medulla analyses showed concordant MRD-DNA results in five of six patients. BM MRD-RNA and MRD-DNA were fully concordant, whereas two discrepancies were observed between MRD-DNA and MRD-RNA in ovarian tissue. These findings suggest potential leukaemic cell persistence in ovarian tissue despite CR and highlight the need for sensitive molecular assays to assess safety prior to ovarian tissue transplantation.