Would you ever consider SRS or WBRT in an asymptomatic pregnant patient with multiple brain metastases?

I agree with @Dr. First Last that radiation can be deferred in an asymptomatic patient and should be considered. However, brain progressive brain metastases can be neurologically debilitating and radiation may need to be considered for a patient that is not delivering soon. The patient will need to meet with a high risk OB to monitor the pregnancy; earlier delivery may be considered to allow for the patient to get onto cancer treatment sooner. I would get input from my physicist too as to the estimated dose to the fetus. Imaging is hard because gadolinium has unknown risk to the fetus and is often avoided by radiologist, however MRI without contrast is safe.

There is demonstrated safety with the Gamma Knife system in pregnant patients.

Wh...

I do not think there is a one-size-fit-all answer. I have come across several circumstances like so. For sure, one will need evaluation by high risk OB. I think it is also crucial to get input from her medical oncologist regarding the prognosis. The type of systemic therapy to be given also has to be considered. Although some targeted agents are also active against CNS disease, the safety in fetus is questionable. There are certainly a lot of moving parts.

If the patient is not expected to live till the fetus is viable (none will ever survive below 22 weeks of gestation), the dose to the fetus will be of secondary importance. However, if the patient is expected to live through the term of the baby and the fetus is close to viable in the sec...

I’d prefer deferring RT if possible to a pregnant patient. I’d want to know how far along the pregnancy is and whether there’s time to defer RT. For an asymptomatic patient I think it would be reasonable to defer.