Highlights from Fertility and Sterility: Washing Ovarian Follicles Effectively Removes Contaminating Malignant Cells
June 11 , 2015
by: ASRM Office of Public Affairs
Published in Fertility and Sterility in press
Belgian researchers have found that a triple-wash technique is effective for cleansing antral follicles (egg-containing cells) isolated from ovarian tissue contaminated with malignant cells, while maintaining the follicles’ viability. This is an essential step in developing a process to preserve fertility for young girls who must undergo chemotherapy to treat childhood cancer, particularly leukemia.
Previous studies have shown that, in more than 50% of cases, ovarian tissue from patients with leukemia contains leukemic cells. These cancer cells could be inadvertently picked up with isolated antral follicles resulting in a reintroduction of a patient’s malignancy if grafted back to her along with her follicles. Therefore, it is important to develop a method to separate cancer cells from antral follicles.
In a prospective experimental study, researchers at a university hospital in Brussels created a model consisting of ovarian tissue artificially contaminated with leukemic cells to evaluate the safety and effectiveness of their antral follicle isolation procedure.
The researchers used donated ovarian tissue from 10 patients undergoing laparoscopy for benign disease. The tissue samples were enzymatically dissociated and the resulting mixtures of cells and follicles were contaminated with measured numbers of fluorescent-marked leukemic cancer cells.
Each sample was divided to create two groups of samples for examination and testing. For the first group, antral follicles were isolated from the cell suspensions using the researchers’ usual cell pick-up technique with no further treatment. In the second group, immediately after pick-up, the antral follicles were put through three simple washes in protein augmented buffered saline.
In the first group of samples, 499 follicles were retrieved, with 196 cancer cells detected by fluorescent microscopy. In the second group, after three washes, one leukemic cell was detected, with 772 follicles retrieved.
The samples, containing a known concentration of leukemic cells, were also analyzed using polyermase chain reaction (PCR) for the presence of a genetic marker for leukemia. Samples which tested positive for the BCR-ABL fusion gene were those in which at least 19 cancer cells were found microscopically. Four samples in the first group tested positive; all of the washed samples in the second group tested negative.
The washing process did not affect the antral follicles’ viability: 96.4% of the washed follicles were alive after processing, as were 95.6% of the unwashed follicles.
Owen Davis, MD, President-Elect of ASRM commented, “Now more than ever, it is likely that young people facing cancer treatment will survive, grow up and want to have children of their own. For girls who need to preserve ovarian tissue, it is essential that we develop ways for them to safely use their tissue without placing their health at risk again. The technique used by the team in Brussels shows great promise in separating leukemic cells from ovarian follicles, an essential pre-requisite for using this tissue.”
Soares et al, Evaluation of a human ovarian follicle isolation technique to obtain disease-free follicle suspensions before safely grafting to cancer patients, Fertility and Sterility, in press.
ASRM is a multidisciplinary organization dedicated to the advancement of the science and practice of reproductive medicine. The Society accomplishes its mission through the pursuit of excellence in education and research and through advocacy on behalf of patients, physicians, and affiliated health care providers. The Society is committed to facilitating and sponsoring educational activities for the lay public and continuing medical education activities for professionals who are engaged in the practice of and research in reproductive medicine.