MADRID—Two new studies suggest that children exposed to chemotherapy or radiotherapy in the womb can be spared negative long-term effects.

At a median age of 6, most of the children exposed to radiation in utero had neuropsychological, behavioral, and general health outcomes that were within normal ranges.

And children who were exposed to chemotherapy in the womb had normal mental and cardiac health at a median age of 2.

“When chemotherapy is administered after the first trimester of pregnancy, we cannot discern any problems in the children,” said Frederic Amant, MD, PhD, of 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.”

Dr Amant and his colleagues presented these findings (abstract 267PD_PR) and their findings on radiation (abstract 49LBA_PR) at the ESMO 2014 Congress.

Outcomes with chemotherapy

In the first study, the researchers recruited 38 children from the International Network for Cancer, Infertility and Pregnancy registry who were prenatally exposed to chemotherapy.

Most of the mothers had breast (61%) or hematologic (22%) cancers. Most were treated with anthracyclines (61%) and had received an average of 4 cycles (range, 1-7) of treatment.

The researchers assessed mental development and cardiac health in the children of these subjects, comparing them to 38 control children who were not exposed to chemotherapy.

At a median age of almost 2 years, mental development was in the normal range for both groups of children, and development was not significantly different between the groups. The mean Mental Development Index score was 99.13 for exposed children and 101.47 for controls.

Cardiac dimensions and functions were within normal ranges for both groups as well. Mean fractional shortening was 36% (range, 32-42) for exposed children and 39% (range, 32-51) for controls. Although the difference was signficant (P=0.004), the researchers said it was not clinically relevant.

“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 fetus and her or his subsequent development,” said Fedro Alessandro Peccatori, MD, PhD, of the European Institute of Oncology in Milan, Italy, who was not involved in this study.

“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.”

Dr Amant said future studies will explore the effects of specific chemotherapy types in detail and include longer-term follow-up.

Outcomes with radiation

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

The study included 16 children, with a median age of 6 years, who had been exposed to radiotherapy in utero. The median maternal irradiation was 48 Gy (range, 12-70), and the median estimated fetal irradiation was 91 mGy (range, 0-1690).

Neuropsychological, behavioral, and general health outcomes were within normal ranges for most of the children. And the researchers found no linear relationship between the fetal dose of radiation and cognitive outcome.

However, there was a negative linear relationship between the gestational age at radiotherapy exposure and verbal intelligence, based on results in 8 children. Two of these children were exposed to radiotherapy in the third trimester and had verbal intelligence scores outside the normal range.

One of the 2 children had low scores on all variables of cognitive development, but other pregnancy-related complications are confounding factors. The child’s mother suffered from an aggressive non-Hodgkin tumor of the brain that impacted her general state, and she had a preterm delivery.

Dr Amant noted that this is based on a very small number of children, so the results should be interpreted with caution.

“We cannot exclude that there might be an impact of prenatal radiotherapy exposure,” he said, “but larger series are needed to further investigate this relationship.”

Cancer treatment during pregnancy can be safe