The number of lung biopsies has increased steadily in recent years. Pneumothorax is the most common complication of a lung biopsy and can occur during the procedure, immediately after the procedure or within a few hours (delayed pneumothorax). The incidence of pneumothorax in the literature is very different from one study to another: it has been reported to be from 9 to 54% in patients undergoing percutaneous transthoracic needle biopsy. This difference of incidence could be explained by the absence of consensus for the definition of an iatrogenic pneumothorax.

The characteristics of pneumothorax and the management of patients with iatrogenic pneumothorax will be evaluated in different centres in a retrospective manner. This study will contribute to refining the criteria for defining pneumothorax occurring during lung biopsy and will provide a better understanding of the condition and its management.

Inclusion Criteria:

• Patients aged 18 years old and more at the time of the biopsy procedure in year 2020
• Having had a pneumothorax following their transthoracic percutaneous lung biopsy in year 2020

Exclusion Criteria:

• Objection to the use of the data (French sites only)

Adult patients who presented with a pneumothorax following their lung biopsy (see eligibility criteria)