About 30-40 children a year are diagnosed with Hodgkin's lymphoma, a type of lymphoma. Children are treated with a combination of chemotherapy and sometimes radiation. Radiation can lead to late effects of treatment, such as second tumors. Therefore, the latest European treatment protocol (EuroNet-PHL-C2) is investigating whether less radiation is needed when children with Hodgkin lymphoma receive higher doses of chemotherapy.
Effect on fertility
‘To reduce late effects, it is good to use less radiation whenever possible. On the other hand, chemotherapy can lead to reduced fertility' says pediatric oncologist Dr. Margreet Veening, who is leading the study. This is why we are investigating the effect of Hodgkin lymphoma treatment on fertility at the Máxima Center. We expect that children who receive more chemotherapy will show more signs of damage.
PhD student Katja Drechsel presented the first results of the study at the annual congress of the European Society of Human Reproduction and Embryology in Copenhagen. She received an award for the best poster presentation on a clinical scientific topic.
Decline and recovery
This study included 206 children from 18 centers in five countries. All children were treated for Hodgkin's disease according to the EURONET-PHL-C2 protocol. They have now completed their treatment and are being followed up. Katja Drechsel and her colleagues are looking at different blood values in both boys and girls that may indicate future fertility. ‘In girls, during treatment we saw a profound decrease in a hormone, AMH, which is related to the number of eggs in the ovaries,' Katja explains. ‘After treatment for Hodgkin's lymphoma, the level of the hormone increased again, which is positive and indicates recovery. But the levels are often still relatively low compared to those of healthy peers, and we have to be careful in our interpretation’.
‘The level of AMH cannot be translated one-to-one into the number of eggs,' says Margreet Veening. ‘It is also very difficult to estimate fertility, especially in young girls. There are many factors that influence the chance of getting pregnant later on. In fact, you only need one good egg to get pregnant. However, the number of eggs you have can give an indication of the age until which you will remain fertile; with a lower egg supply, you have a chance of going through menopause earlier.’
Sperm quality
In the study, Katja Drechsel and colleagues also look at the effect of treatment on fertility of boys who are treated for Hodgkin's lymphoma. They measure the hormones FSH and Inhibin B in the blood and look at the sperm quality before and after treatment. Katja: ‘In boys, we see that the hormones often become abnormal during chemotherapy and often normalize again after the end of treatment. The Hodgkin's disease itself also seems to negatively affect sperm quality before treatment. Two years after treatment, we see signs of damage in about half of the boys who donated sperm. We do not yet know how much recovery will occur. That’s why we will repeat the sperm test five years after diagnosis.’
The findings in the boys and girls will be used to develop the future treatment protocol for Hodgkin lymphoma.
Extensive attention
At the Princess Máxima Center, fertility receives a lot of attention, in good cooperation with colleagues at the UMC Utrecht. Irene IJgosse is closely involved as a nurse specialist. ‘Children and parents experience the effect of treatment on fertility as a very important aspect of their quality of life,’ she says. ‘We inform them about the risks and possibilities. New research improves our knowledge, so that we can advise and guide children and parents based on the latest evidence’.