Secondary spontaneous pneumothorax in cancer patients

Malignancy-associated secondary spontaneous pneumothorax (MSSP) poses significant challenges due to limited survival. By assessing risk factors associated with a MSSP recurrence, there is potential to identify patients who could benefit from early intervention intended to prevent recurrence.

We performed a retrospective cohort study of patients with MSSP. The primary outcome was time to MSSP recurrence. We used a competing risk model to identify risk factors associated with MSSP recurrence.

A total of 2,532 patients were diagnosed with pneumothorax, with 114 having MSSP but only 96 were evaluable for the time-to-recurrence analysis. Of the 96 patients, 9 (9.4%) patients experienced recurrent MSSP, and 58 (60.4%) patients died during the study's follow-up period. The estimated cumulative incidence (CI) of MSSP considering death as a competing risk was 10.1% at 15 months. The univariable model identified the following covariates as associated with MSSP recurrence: mediastinal shift (HR 12.30, 95% CI: 3.44-43.91, P<0.001), distance from lung apex to thoracic cupola (HR 1.02, 95% CI: 1.00-1.03, P=0.003), and distance between visceral and chest wall at the hilum (HR 1.02, 95% CI: 1.00-1.03, P=0.026).

Although the incidence of MSSP recurrence was found to be low, clinical factors such as sarcoma, the associated mediastinal shift, greater distance from lung apex to thoracic cupola, greater distance between visceral and chest wall at the hilum were found to be risk factors for MSSP recurrence.