A British man has become the first in the world to successfully father a child after a testicular transplant following life-saving chemotherapy.
The man suffered from Hodgkin鈥檚 lymphoma 鈥� a type of blood cancer. He had testicular tissue removed and frozen before undergoing chemotherapy to destroy the cancer cells. More than 95 percent of patients receiving this type of chemotherapy are left permanently sterile.
A team led by John Radford, professor of medical oncology at Christie Hospital in Manchester, UK, removed mature germ cells from the patient鈥檚 testes during a biopsy. Each of these cells is capable of producing many sperm. The cells were frozen and stored in liquid nitrogen. Two years later, when the patient鈥檚 cancer was in remission after chemotherapy, the germ cells were defrosted and reimplanted into his testes.
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The transplanted testicular cells successfully began to divide and multiply, and the patient鈥檚 wife has since become pregnant with his child.
John Radford, Professor of Medical Oncology at Christie Hospital in Manchester, UK, who led the research, called the results 鈥渆ncouraging鈥�. However, Radford points out that this patient was one of seven in a clinical trial 鈥� and he is the only one so far to have produced sperm.
Spontaneous sperm
鈥淲e cannot draw a positive conclusion from this one pregnancy, because there is a small chance that the patient would have regained his sperm count spontaneously,鈥� Radford adds. 鈥淚n animal trials we are able to transplant marked cells, so we know for sure we have been successful there, but we cannot use marked cells in humans.鈥�
鈥淭he trials are still at an early stage. If three or four of the seven produced a sperm count we could point definitely at the transplant,鈥� Radford told New 杏吧原创.
Until now, the only method of preserving male fertility has been freezing sperm samples. But conceiving in this way is expensive, and has limited success because it requires IVF treatment. Also, prepubescent boys with cancer are unable to benefit, since they do not produce sperm 鈥� although they do have immature testicular germ cells.
Room for error
Transplanting reproductive tissue has had limited success in people. Several teams have transplanted strips of defrosted ovarian tissue back into women. But only one has ovulated, and none has become pregnant.
But sperm germ cells are much easier to remove and reintroduce than ovarian tissue, says Christopher Barratt, professor of reproductive medicine at Birmingham University, UK. 鈥淵ou get many more germ cells and at different stages in the testes. In ovarian cell transplants, there is a much greater room for error,鈥� Barratt said.
One of the main concerns about transplanting reproductive tissue following cancer is that the transplanted tissue itself might contain cancerous material. But for male patients with Hodgkin鈥檚 disease, this should be very unlikely, says Radford.
鈥淚n Hodgkin鈥檚 disease, testicular involvement is unheard of. The risk is greater for women because their ovaries are located in the abdominal cavity where the cancer is more easily spread,鈥� Radford says. 鈥淗owever, experiments in mice have shown no evidence of transmission of lymphoma after ovarian transplant.鈥�