Anaplastic Lymphoma Kinase-Tyrosine Kinase Inhibitor Treatment for Metastatic Non-small Cell Lung Cancer Throughout the Entire Gestation Period.

Non-small cell lung cancer (NSCLC) occasionally develops in younger, fertile patients. This early-onset NSCLC tends to have more oncogenic driver mutations than in aged patients. Among early-onset NSCLC patients, pregnancy is very rare. However, there are some patients who were able to balance tyrosine kinase inhibitor (TKI) administration and pregnancy. Here, we report a case of a pregnancy under alectinib hydrochloride (a second-generation anaplastic lymphoma kinase (ALK)-TKI) administration throughout the entire gestational period for ALK-rearranged metastatic lung adenocarcinoma. The patient was an Asian female in her early 20s who became aware of her pregnancy after diagnosis and the start of alectinib administration. She intended to have the baby despite the necessity of continuing her treatment and the unknown risks involved. A multidisciplinary team (thoracic surgeon, obstetrics, pediatrics, and so on) was organized to support the patient, baby, and family. There were no obvious signs of tumor progression during pregnancy. She gave birth at 41 weeks and one day of gestation. There was no placental metastasis. Alectinib concentration at delivery was 155 ng/mL in maternal blood, 22.1 ng/mL in umbilical cord venous blood, 20.1 ng/mL in amniotic fluid, and 11.8 ng/mL in colostrum. The baby had been exposed to alectinib throughout the entire pregnancy; however, fetal growth curve parameters remained within the normal ranges and the baby developed without anatomical or neurodevelopmental anomalies or fetal metastasis for the first 13 months of age.