Abstract Introduction The incidence of lung cancer (LC) in young adults is rising. Management in pregnant patients is complex, requiring careful maternal and fetal monitoring. Adenocarcinoma in young adults often harbors molecular alterations necessitating targeted therapies, but pregnant women are routinely excluded from clinical trials, leaving limited data on tyrosine kinase inhibitor (TKI) pharmacology, fetal safety, and outcomes. Case We report here the case of a 37-year-old pregnant woman at 19 weeks of gestation diagnosed with stage M1b EGFR-mutated lung adenocarcinoma in 2019.A CT scan revealed a right upper lobe lung mass with ipsilateral hilar lymphadenopathy. Brain MRI identified a 14 mm metastasis. Bronchial biopsies confirmed a TTF1-positive lung adenocarcinoma with an EGFR exon 19 deletion. The patient underwent a right upper and middle bilobectomy (T3N1, R0) and resection of the cerebellar metastasis. Gefitinib (250 mg daily) was started at 27 weeks of gestation, two weeks post-surgery. Fetal monitoring showed no malformations or abnormalities, with stable growth. Labor was induced at 37 weeks, and a healthy baby boy was delivered vaginally. Placental histopathology was normal, with no cancer metastases.Cord blood analysis revealed fetal gefitinib A cord blood sampling revealed a gefitinib concentration of 28 ng/mL, compared to 189 ng/mL in the maternal blood. The newborn had normal hematology and liver function and, at 5 years old, demonstrates normal pediatric development. Discussion This case report highlights the challenges of managing lung cancer during pregnancy. Molecular testing and careful fetal monitoring are essential. At 19 weeks of gestation, delaying treatment or terminating the pregnancy was unacceptable, yet cancer therapy during pregnancy poses fetal risks. Surgical interventions, including bilobectomy and metastasis resection, can be safely performed during pregnancy when necessary. Chemotherapy and targeted therapies can cross the placenta, with the highest risk of malformations in the first trimester. .EGFR plays a role in placental development, but treatment after 14 weeks carries a lower teratogenic risk, though intrauterine growth restriction and oligohydramnios remain concerns. Studies show limited genotypic profiling and treatment for pregnant women with EGFR-mutated LC, and many did not receive targeted therapy despite oncogenic addiction.Targeted therapies, such as EGFR TKIs, may be safer than chemotherapy; transplacental transfer is low, and fetal toxicity is generally mild to moderate. In this case, gefitinib administered during the second and third trimesters did not appear to cause any adverse effects on the developing fetus or any long-term effects detectable during the child’s development. This abstract is funded by: None
Messekher et al. (Fri,) studied this question.