The efficacy and safety of intrapleural hyperthermic perfusion in patients with malignant pleural effusion undergoing video-assisted thoracic surgery: a single-arm clinical trial.

Background: Patients with malignant pleural effusion (MPE) are usually treated with an indwelling pleural catheter (IPC) or pleurodesis. However, most do not achieve a satisfactory control rate of pleural effusion and have poor prognosis. Distilled water has cytocidal effects of hypotonic shock and can result in the lysis of cancer cells which was used in surgery to eradicate cancer cells. However, there is no study focusing on the efficacy of intrapleural hyperthemic perfusion for MPE under video-assisted thoracoscopic surgery (VATS). This study explored the efficacy and safety of intrapleural hyperthermic perfusion (IHP) with distilled water in patients with MPE. Methods: In this retrospective, single-arm trial, patients admitted to department of cardiothoracic surgery of Taizhou hospital and diagnosed with MPE caused by non-small cell lung cancer from January 2014 and December 2018 were included. The clinical characteristics including age, gender smoking history, Karnofsky score, volume of pleural effusion, TNM cancer stage, pathology, genetic test of patients were collected. Patients were treated with hyperthermic perfusion. The pleural cavity was perfused with 43.0 ℃ distilled water for 60 minutes under video-assisted thoracic surgery (VATS). The efficacy of treatment was defined as follows: (I) complete remission (CR; no recurrence of pleural effusion after IHP for at least four weeks); (II) partial remission (PR; pleural effusion was decreased by 50% and the condition lasted for 4 weeks; or (III) no remission (NR; no decrease in pleural effusion). Kaplan-Meier method with a log-rank test was used for survival analysis. Cox proportional hazards regression models were applied to perform univariate and multivariate analyses. Results: From January 2014 through December 2018, 30 patients with MPE caused by non-small cell lung cancer (NSCLC) were treated with hyperthermic perfusion. There were no serious reportable clinical complications associated with the procedure. The response rate was 96.7%, with 63.3% experiencing PR and 33.3% achieving CR. The overall survival (OS) ranged from 2 to 46 months. The median survival was 12 months. Conclusions: IHP proved to be a feasible and safe strategy for patients with MPE in our study but it still needs to be verified with a larger, prospective and randomized trial in the future.