Some Women Diagnosed With Cancer During Pregnancy Can Get Chemo Safely
NEW YORK (Reuters Health) - Some women diagnosed with cancer during pregnancy can undergo chemotherapy with little risk to their unborn children, according to findings from the International Network on Cancer, Infertility and Pregnancy (INCIP) registry.
"Cancer treatment during pregnancy is an option,” Dr. Frederic Amant from KU Leuven, in Belgium, told Reuters Health by email. “In some cases, however, it’s not, and this needs to be evaluated case by case.”
Cancer develops in an estimated 1 in 1,000 pregnancies, and how best to manage it remains unclear, Dr. Amant and his colleagues write in The Lancet Oncology, online January 24. An earlier report from the INCIP registry found no significant differences in neurocognitive or cardiac development between children with or without antenatal chemotherapy exposure.
Dr. Amant and colleagues used INCIP registry data to describe oncological, obstetric and neonatal outcomes among 1,170 women diagnosed with primary invasive cancer or borderline ovarian cancer during pregnancy between 1996 and 2016.
Overall, 67% of these women received cancer treatment during pregnancy, including surgery (39%), chemotherapy (37%), radiotherapy (2%), targeted and hormonal therapy (3%), or other therapy (4%).
Among singleton pregnancies, 2% ended in a miscarriage and 9% were terminated. The main reasons for termination were initiation of oncological treatment or poor maternal prognosis, unwanted pregnancy and fetal anomalies. Only five patients (<1%) died during pregnancy.
All but 1% of singleton pregnancies ended in a live birth, although half of the deliveries were preterm. A fifth (21%) of children were small for gestational age, and 41% of children with available data required NICU admission, mostly related to prematurity.
Congenital malformations were reported in 4% of live-born singletons.
Chemotherapy appeared to increase the risk of small for gestational age and NICU admission, whereas the data suggested a relationship between abdominal or cervical surgery and reduced NICU admission.
NICU admission was most commonly associated with gastrointestinal cancer and least commonly associated with thyroid cancer.
Every five years between 1996 and 2016 were associated with a 10% increased likelihood of receiving treatment during pregnancy (mainly related to a 31% increased likelihood of receiving chemotherapy), a 4% increase likelihood of live birth among singleton pregnancies, a 7% reduction in the risk of preterm live birth, a 9% reduction in the risk of iatrogenic preterm live birth and a 9% reduction in the risk of NICU admission.
“I am most happy with the change in policy,” Dr. Amant said. “When we started this project, the threshold to treat cancer during pregnancy was very high, with a corresponding low threshold to terminate or induce (labor) prematurely. This now seems to have changed, and we hope this will further improve in the future.”
“Cancer during pregnancy is a complex situation and few teams have experience, so referral to large multidisciplinary centers is best for mother and her baby,” he said. “A perinatologist needs to be involved.”
“We need to collect more data on the long-term safety, and this is currently ongoing in the framework of INCIP,” Dr. Amant said.
In a related editorial, Dr. Christhardt Koehler from Asklepios-Clinic Hamburg, in Germany, and Dr. Simone Marnitz from the University of Cologne, also in Germany, urge caution when interpreting the new findings. "First," they write, "a reporting bias cannot be excluded, because the expert centers contributing to the database did not represent the full spectrum of pregnant women diagnosed with cancer."
Second, the perinatal outcomes are based on little more than half of the patients, and third, the finding of a protective effect of cervical or abdominal surgery on NICU admission lacks a physiological explanation.
Finally, they question the researchers' recommendation to prolong oncological therapy in pregnancy to avoid preterm delivery, as it seems to contrast with the reported maternal mortality and fetal deaths.
The editorial concludes that “due to its heterogeneity, the INCIP database analysis reported (here) has minor value for women’s oncological management. Carefully planned studies combining women’s cancer-specific management in pregnancy, oncological outcomes, and long-term effects on children’s development are urgently needed to improve our limited knowledge.”
Lancet Oncol 2018.
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