The treatment of pleural effusions in cancer patients: circulating prognostic biomarkers

The treatment options for cancer patients with malignant pleural effusion are rather limited. Both the diagnosis and prognosis remains to be challenging and the individualized therapeutic decision requires a set of validated biomarkers.

77 cancer patients with pleural effusions were treated at the Department of Thoracic Surgery, Ruhrlandklinik, between July 2016 and March 2017. Preoperative C-reactive protein, white blood cell count and clinical follow-up data was collected. The influence of clinicopathological parameters on overall survival was calculated by Mantel-Cox tests.

36 non-small cell lung cancer, 3 small cell lung cancer, 17 malignant pleural mesothelioma and 21 patients with extrathoracic primary tumor was included in the study. 38 patients had malignant effusions. Pleurodesis was performed in 12 cases, talcum was applied in 9 interventions and 55 patients received a pleural catheter. There was no significant difference in the mean CRP or WBC in patients with malignant or non-malignant effusions. As expected, patients with malignant effusions had a significantly shorter overall survival (HR: 5.5, CI95% 1.09 – 28.6, p = 0.039). Importantly, both high CRP (> 5 mg/dl, HR: 0.08, CI95% 0.01 – 0.5, p = 0.009) and high WBC (> 9000 cells per microliter, HR: 0.12, CI95% 0.02 – 0.6, p = 0.011) was a strong predictor of shorter survival among patients with malignant effusions.

Our data suggests that circulating biomarkers can contribute to the risk stratification of cancer patients with malignant pleural effusions.