Children who are exposed to chemotherapy or radiotherapy while in the womb suffer no negative impacts on mental or cardiac development, international studies presented at the ESMO 2014 Congress in Madrid have shown.

“When chemotherapy is administered after the first trimester of pregnancy, we cannot discern any problems in the children,” says lead author Dr Frederic Amant, University Hospitals Leuven in Belgium.

“Fear about the risks of chemotherapy administration should not be a reason to terminate a pregnancy, delay cancer treatment for the mother, or to deliver a baby prematurely.”

Concerns about the potential impact of cancer treatment on unborn children has until recently left some oncologists hesitant to administer treatments to pregnant cancer patients, says Amant.

To address these concerns, his group has led three new studies presented at ESMO 2014.

In the first study, 38 children prenatally exposed to chemotherapy were recruited from the International Network for Cancer, Infertility and Pregnancy (INCIP) registry and assessed for mental development and cardiac health.

Their outcomes were compared to 38 control children who were not exposed to chemotherapy.

At a median age of almost two years of age, mental development as measured by the Mental Development Index was in the normal range for both groups of children, and were not significantly different.

Cardiac dimensions and functions were within normal ranges for both groups.

This is the first case control study on the developmental outcome of children exposed in utero to chemotherapy.

It shows that chemotherapy during pregnancy can be considered safe for mental development and cardiac functioning of the child, the authors say.

Commenting on the results, Dr Fedro Alessandro Peccatori, Director of the Fertility & Procreation Unit at the European Institute of Oncology’s Division of Gynaecologic Oncology, who was not involved in the study, said that these results confirm that chemotherapy administration during pregnancy does not alter neurodevelopment after birth, nor cause cardiac alterations.

“This paper points to the very important issue of long-term safety of prenatal exposure to chemotherapy and reinforces the notion that chemotherapy during gestation does not endanger the foetus and her or his subsequent development. To further ameliorate neonatal outcome, a special effort should be made to prolong pregnancy duration, and stringent long-term follow-up should be pursued to confirm these findings. Meanwhile, specific measures to support prematurely delivered babies and their families should be implemented."

Future studies will explore the effects of specific chemotherapy types in detail, and longer term follow-up, to fine tune the findings.

In a second study, Amant and colleagues explored the impact of radiotherapy on the children of women with cancer.

The study included 16 children and 10 adults who had been exposed to radiotherapy in utero.

This is the first long-term follow-up study of children prenatally exposed to medical radiation, and the study showed that neuropsychological, behavioural and general health outcomes for those exposed to radiotherapy were within normal ranges.

One child revealed a severe cognitive delay, however other pregnancy-related complications are confounding factors, they report.

Amant hopes the new results will provide clinicians with the evidence they need to ensure pregnant women with cancer receive the best quality care.

“It’s a good feeling to know that research data can be implemented immediately into the clinic. Our data will inform physicians and patients and help them to take decisions in a difficult situation.”

Commenting, Peccatori noted that the long-term follow-up of children and adults whose mothers have been treated with radiation therapy during gestation is an important topic.

“The main message is that neuropsychological, behavioural and general health outcomes were within the normal range in all, but 3 of the 16 children studied. This is the first long-term follow-up study of children and adults exposed to radiotherapy in utero. Pregnancy, particularly advanced pregnancy, has been traditionally considered a contra-indication to radiotherapy. New radiation techniques and more sophisticated simulations of the received fetal dose may change this scenario, but caution remains mandatory when giving radiotherapy to a pregnant woman, particularly in the third trimester.”

Source: ESMO

Watch Prof Amant's press conference at ESMO here.