Biopsy: principles, technical considerations, and pitfalls.

Biopsy is an essential part of the diagnostic workup for cancer patients. Percutaneous, endoscopic, catheter, incisional, and excisional biopsies have different indications, accuracy, and efficacy. Careful attention to biopsy technique will minimize complications and increase the accuracy and efficacy of the biopsy procedure. Intraoperative biopsy and microscopy can be used in selected instances to modify the surgical plan.