Background: Pneumothorax is a rare but recognized complication of diagnostic needle aspiration of the breast. Two recent court cases alleging negligence have reached opposing opinions on very similar findings.
Methods: A Medline literature search was carried out.
Results: The reported incidence of pneumothorax after diagnostic aspiration of the breast in seven series varied between three in 100 and one in 10 000, but the weight of evidence tended towards the latter rate. Two studies reported that the complication is more common in the hands of trainees. It is not always possible to maintain the aspirating needle parallel or tangential to the chest wall. Pleural puncture may be more common than is apparent, and is most common in the tail of the breast in a thin woman.
Conclusion: It is important that breast clinicians are aware of the risk of pneumothorax but, provided proper care has been taken, this complication is not the result of a negligent act.