A new method for evaluating the risk of transferring leukemic cells with transplanted cryopreserved ovarian tissue

This study aimed to develop a method to detect ovarian residual disease by multicolor flow cytometry in acute leukemia patients. We designed an experimental model consisting in adding acute leukemia cells to a cell suspension obtained from healthy ovarian cortex. Leukemic cell detection within the ovarian cell suspension required the development of a specific myeloid antibody panel different from that commonly used for minimal residual disease (MRD) monitoring in bone marrow. The method was then used to detect ovarian residual disease in 11 acute leukemia patients. Multicolor flow cytometry is able to evaluate the presence of viable leukemic cells in the ovarian cortex with good specificity and robust sensitivity of 10-4. We observed a good correlation between multicolor flow cytometry and quantitative polymerase chain reaction results. Ovarian residual disease detection by multicolor flow cytometry was positive in 3 out of 11 acute leukemia patients. Multicolor flow cytometry can potentially be applied to ovarian tissue from all acute leukemia patients and is essential to evaluate the risk of cancer re-seeding before autograft of ovarian tissue in case of acute leukemia.