Fine-needle aspiration biopsy is a rapid, inexpensive, atraumatic, and accurate way of diagnosing many cancers. It can be applied to any palpable mass. Deep lesions can also be sampled if visualization is guided by computed tomography, ultrasound, or fluoroscopy. Proper technique is essential in obtaining biopsy material, and interpretation of the smear requires special training. Patients accept the procedure, and even a repetition of it if necessary, very well.