Survival in Patients With Malignant Pleural Effusions Who Developed Pleural Infection

Abstract

Malignant pleural effusion (MPE) incidence is increasing, and prognosis remains poor. Indwelling pleural catheters (IPCs) relieve symptoms but increase the risk of pleural infection. We reviewed cases of pleural infection in patients with IPCs for MPE from six UK centers between January 1, 2005, and January 31, 2014. Survival in patients with pleural infection was compared with 788 patients with MPE (known as the LENT [pleural fluid lactate dehydrogenase, Eastern Cooperative Oncology Group performance status, serum neutrophil to lymphocyte ratio, and tumor type] cohort) and with national statistics. Of 672 IPCs inserted, 25 (3.7%) became infected. Most patients (20 of 25) had mesothelioma or lung cancer. Median survival in the pleural infection cohort appeared longer than in the LENT cohort, although this result did not achieve significance (386 days vs 132 days; hazard ratio, 0.67; P = .07). Median survival with mesothelioma and pleural infection was twice as long as national estimates for mesothelioma survival (753 days vs < 365 days) and double the median survival of patients with mesothelioma in the LENT cohort (339 days; 95% CI, nonoverlapping). Survival with lung and breast cancer did not differ significantly between the groups. Sixty-one percent of patients experienced early infection. There was no survival difference between patients with early and late infection (P = .6). This small series of patients with IPCs for MPE suggests pleural infection may be associated with longer survival, particularly in patients with mesothelioma. Results did not achieve significance, and a larger study is needed to explore this relationship further and investigate whether the local immune response, triggered by infection, is able to modulate mesothelioma progression.