For a palpable breast mass in a woman under 30 years old, what is the initial imaging modality?

• A. Mammography
• B. CT scan
• C. Ultrasound
• D. MRI

Answer: (C)

In young women, breast tissue is typically dense, which makes mammography less reliable as a first test. Ultrasound is the best initial imaging because it accurately distinguishes cystic from solid masses in dense tissue, is radiation-free, widely available, and can be done quickly. It also allows real-time assessment and can guide needle biopsies if needed. If the ultrasound shows a simple cyst, it may just be observed or aspirated. If the lesion is solid or complex, further evaluation with biopsy is considered. CT isn’t used for breast imaging due to poor soft-tissue detail and radiation, and MRI, while very sensitive, is not used first-line because it’s more costly and typically reserved for problem-solving in specific scenarios.