Ovarian tissue cryopreservation and transplantation has apparently led to 13 live births in women with lymphoma or solid tumors. In this procedure, ovarian tissue is excluded and allowed to freeze before the patient undergoes aggressive chemotherapy and radiotherapy. The tissue is seemingly implanted again when the cancer has been brought under control. Experts declare this fertility preservation method to be hazardous for patients with leukemia.
Leukemia patients may run a risk of their frozen-thawed ovarian tissue to protect malignant cells and encourage a recurrence of the disease after reimplantation. It has been revealed that acute lymphoblastic leukemia (ALL) is commonly discovered in younger people, so preservation of their fertility is very important. In fact the disease is believed to be diagnosed in individuals especially under the age of 35 years.
“Our study provides clear evidence that cancer cells in women with acute and chronic leukemias can contaminate the ovaries. If this tissue is reimplanted in these women when they’re ready to have children, there’s a good possibility that the cancer will come back,” added Marie-Madeleine Dolmans, MD, professor at the Université Catholique de Louvain in Brussels and lead author of the study.
Aggressive chemotherapy and radiotherapy are already believed to hamper the reproductive organs. Hence, experts aimed to determine the safety of utilizing ovarian tissue cryopreservation to protect the fertility of patients with leukemia. The effects of the technique were tested on 12 women with ALL, which is a fast-growing cancer of the white blood cells. The experiment was also conducted on 6 women with CML that is a gradually progressing bone marrow cancer.
All the study subjects were between the age group of 2 and 31 years and had their ovarian tissue cryopreserved from 1999 to 2008. While the mean age of the patients with ALL was 14.5 years, for CML patients it was 24.7 years. In the early stages wherein a microscopic examination was undertaken, no cancerous cells appeared in the ovarian tissue samples accumulated from each patient. These tissue samples were taken by real-time quantitative polymerase chain reaction (RT-qPCR) technique.
Brandon Hayes-Lattin, MD, the Director of the Adolescent and Young Adult Center at the Knight Cancer Institute in Portland, Oregon, commented, “Leukemia patients can benefit from fertility preservation techniques. But the strategies offered must be both effective and safe. Among its other strengths, this work emphasizes that molecular methods can be successfully applied to assessments of safety.”
It was affirmed that 70 percent of the ALL patients had cancerous cells in the ovarian tissue. Around 33 percent of the CML patients reported the presence of cancerous cells in their ovarian tissue. While initiating further analysis, researchers engrafted the ovarian tissue samples into 18 healthy mice for an observational period of six months. It was observed that mice provided with tissue from CML patients had grafts that appeared normal with no presence of any cancerous cells.
Four mice that were given ovarian tissue from ALL patients seemingly developed tumors. Having employed the RT-qPCR and the mouse model, the experts showed the viability and malignant potential of leukemic cells found in the frozen ovarian tissue, particularly from ALL patients. Further investigations can be triggered for ascertaining safer options for fertility preservation in patients with acute and chronic leukemias.
The research is published online in Blood, the journal of the American Society of Hematology.