Delays in diagnosis are common, with an average reported delay of 5 to 15 months from the onset of symptoms. If an abnormality is found, diagnostic approaches such as ultrasound and mammography may be used. With proper shielding, mammography poses little risk of radiation exposure to the fetus. However, mammograms should only be used to evaluate dominant masses and to locate occult carcinomas in the presence of other suspicious physical findings. Diagnosis may be safely accomplished with a fine-needle aspiration or excisional biopsy under local anesthesia.
Nuclear scans cause fetal radiation exposure.
If such scans are essential for evaluation, hydration and Foley catheter drainage of the bladder can be used to prevent retention of radioactivity. Timing of the exposure to radiation relative to the gestational age of the fetus may be more critical than the actual dose of radiation delivered. Doses of 10 rad may result in fewer defects. However, no data evaluating the safety of MRI during pregnancy are available. Carcinogenesis in the fetus exposed to radiation is another consideration.