Which type of biopsy is least invasive?

Needle biopsy is the least invasive type of biopsy among the options provided. This method involves the use of a thin, hollow needle to extract tissue or fluid samples from a suspicious area, such as a tumor. Because this procedure typically does not require any large incisions or major surgical interventions, it can be performed on an outpatient basis with minimal anesthesia, often just local anesthesia.

In contrast, excisional biopsy involves the complete removal of a tumor or suspicious area, which requires making an incision in the skin, thus being more invasive. Incisional biopsy, while not removing the entire mass, still requires a surgical incision to obtain a portion of the tissue, making it more invasive than a needle biopsy. Open surgical biopsy also involves larger incisions and general or significant local anesthesia, which adds to its invasiveness.

Overall, the needle biopsy provides a less traumatic option for procuring tissue and is often sufficient for diagnosis, contributing to a lower risk of complications and faster recovery for patients.