Percutaneous needle biopsy of deep pelvic masses: a posterior approach.

The classical approach for the fine-needle aspiration biopsy of deep pelvic masses has been through the lower anterior abdominal wall. With this approach, and using either CT or sonographic guidance, bowel or bladder may be unavoidably traversed to reach the mass. We have been using a posterior approach through the sciatic notch, which is a safe and simple procedure, with good results. The biopsy is done with the patient in a prone position, using a 22-gauge biopsy needle. With this technique we have successfully biopsied various neoplastic pelvic entities.