Astrocytoma in Pregnancy

Headache and vomiting suddenly developed in a 41-year-old woman who was 16 weeks pregnant. The next day, she suffered an episode of tonic-clonic seizures associated with a 15-minute loss of consciousness.

The neurologic examination was unrevealing. However, MRI of the brain demonstrated a prominent white matter, low-density lesion in the right occipitoposterior region. Results of a stereotactic biopsy of the mass were consistent with a diagnosis of astrocytoma (A and B).

Drs Hesham Taha, D. Thai, Gamil Kostandy, H. Fostade, and David Dosik of New York Methodist Hospital, Brooklyn, report that although cancer is a leading cause of death in women of childbearing age, its occurrence in pregnancy is uncommon, with a reported incidence of .07% to 1%. Primary brain tumors affect only about 1% of the general population. Thus, the simultaneous occurrence of a brain tumor in pregnancy is extremely rare, particularly since these tumors tend to develop in women who are beyond their childbearing years.

Pregnancy has a dramatic effect on some types of brain tumors. The rapid enlargement of the mass may be caused by fluid retention and the increased blood volume associated with pregnancy. Additionally, hormonal changes may favor the growth of some tumors.

MRI is the diagnostic method of choice for brain lesions in pregnant women; CT scans risk exposing the fetus to ionizing radiation. Management is also a challenge. Abortion may be appropriate when the diagnosis is made in the first trimester. Treatment decisions must be made on a patient-by-patient basis during the second or third trimester. However, all patients must be given anticonvulsant medications; the risks of seizure-induced maternal and fetal hypoxia and acidosis far outweigh the infrequent deleterious effects of the drugs.

Corticosteroids can be given to reduce edema and minimize symptoms of brain tumors. Prednisone is preferred during pregnancy because it is metabolized before it crosses the placenta.

Increased abdominal pressure during the second stage of labor significantly raises intracranial pressure. Therefore, once labor has begun, cesarean section or use of forceps to shorten the second stage of labor is desirable, especially in nulliparous women. Multiparous women can tolerate vaginal delivery without a serious increase in intracranial pressure.

This patient was given anticonvulsant and corticosteroids; an infant was delivered by cesarean section. After delivery, the brain mass was resected; radiation therapy followed.