Biopsy types
A needle biopsy uses a thin needle to withdraw cells or fluid, often guided by imaging, and is the least invasive option. A core biopsy uses a larger, hollow needle to remove a small cylinder of tissue, giving more material than a needle biopsy without a full surgical procedure. An excisional biopsy surgically removes an entire lump or suspicious area; an incisional biopsy removes only a portion of it, usually when the area is too large to remove entirely for a first diagnosis. Which type is used depends on the tumor's location and size, and on how much tissue the pathologist needs to make a confident diagnosis.