# Intrapleural Administration of Hypotonic Cisplatin for Patients With Malignant Pleural Effusions and Non‐Expandable Lungs

## TL;DR

Intrapleural hypotonic cisplatin reduced or stabilized fluid buildup in patients with lung cancer and non-expandable lungs, offering a potential treatment option.

## Contribution

Demonstrates the efficacy and safety of hypotonic cisplatin for malignant pleural effusions in patients with non-expandable lungs.

## Key findings

- Mean drained fluid volume per day decreased by 65% after treatment.
- At 4 weeks, 53.2% of patients showed reduced pleural effusion.
- Median thoracentesis-free survival was 456 days with 86.1% 30-day survival rate.

## Abstract

Thoracostomy and pleurodesis are the mainstay of management for malignant pleural effusions (MPEs). However, pleurodesis may not be effective for patients with MPEs and non‐expandable lungs. Intrapleural chemotherapeutic agents such as hypotonic cisplatin are reportedly useful for treating MPEs with expandable lungs; however, their efficacy in patients with non‐expandable lungs remains unclear. We aimed to analyze the efficacy and safety of intrapleural administration of hypotonic cisplatin in patients with MPEs and non‐expandable lungs.

We retrospectively analyzed patients with MPEs of thoracic malignancies who were administered intrapleural hypotonic cisplatin. We investigated the changes in drained fluid volume, radiological outcomes at 4 weeks, thoracentesis‐free survival, and adverse events. Between June 2009 and September 2022, 62 patients with MPEs received 69 administrations of hypotonic cisplatin.

The most frequent primary site was the lungs (90.3%), and the mean drained fluid volume per day decreased by 65% (95% confidence interval [CI] 58%–72%) after intrapleural hypotonic cisplatin administration. At 4 weeks post‐administration, MPE volumes decreased in 33 (53.2%) patients, remained unchanged in 22 (35.4%), and increased in seven (11.3%), based on frontal plane chest radiographs. The median thoracentesis‐free survival was 456 days (95% CI, 122–842 days), the 30‐day thoracentesis‐free survival rate was 86.1%, and the 90‐day survival rate was 70.8%. In total, 37 patients (59.7%) were censored. The most frequent adverse event was pleural empyema, observed in four patients.

Intrapleural hypotonic cisplatin administration decreased or stabilized pleural effusion and may be useful for suppressing MPE with non‐expandable lungs.

ClinicalTrials.gov identifier: E23‐0003.

Intrapleural administration of hypotonic cisplatin (HPT) decreased or stabilized pleural effusions and was well tolerated in patients with malignant pleural effusion and non‐expandable lungs.