Malignant Pleural Effusion Interventions: What Matters Most to the Patient?

In the United States, the estimated incidence of malignant pleural effusion (MPE) exceeds 175,000 annually.¹ Cancers of the lung, breast, and ovaries comprise approximately 75% of MPE cases, in which dyspnea is the most common symptom.¹ The median survival period in MPE is 3 to12 months, with the shortest period observed in patients with lung cancer.¹

The recent open-label AMPLE-2 trial (Australasian Malignant Pleural Effusion-2; Australian New Zealand Clinical Trials Registry Identifier: ACTRN12615000963527) compared outcomes of daily (n=43) vs symptom-guided (n=44) drainage regimens after the indwelling pleural catheter insertion in patients with MLE at 11 international centers.² The results demonstrated no differences between groups in the primary outcome of mean daily breathlessness score, as measured via 100-mm visual analogue scale (geometric means, 13.1 mm [95% CI, 9.8-17.4 mm] vs 17.3 mm [95% CI, 13.0-22.0 mm]; ratio of geometric means, 1.32 [95% CI, 0.88-1.97]; P =.18).

Significant differences were observed in the daily vs symptom-guided groups in the secondary outcomes of spontaneous pleurodesis at both 60 days (37.2% vs 11.4%; P =.0049) and 6 months (44.2% vs 15.9%; P =.004; hazard ratio [HR], 3.287 [95% CI, 1.396-7.740]; P =.0065), and patient-reported quality of life as assessed with the EuroQoL-5 Dimensios-5 Levels (estimated means, 0.713 [95% CI, 0.647-0.779] vs 0.601 [95% CI, 0.536-0.667]; estimated difference in means, 0.112 (95% CI, 0.0198-0.204; P =.0174).

There were no significant differences in mortality, pain scores, or days spent in hospital. The rate of serious adverse events, which often included pleural infection, was 25.6% in the daily group vs 27.3% in the symptom-guided group.

In a related commentary published in the same issue of Lancet Respiratory Medicine in which the AMPLE-2 results were reported, David E. Ost, MD, MPH, a professor in the department of pulmonary medicine at the University of Texas MD Anderson Cancer Center in Houston, stated that the AMPLE-2 findings “highlight principles relevant to the study of palliative interventions for malignant pleural effusion” in illustrating the risk for false inferences associated with using incidence proportions in such research.³

Because incidence proportions show outcomes at an arbitrary time point, this method can lead to different conclusions based on the chosen time point. At the 60-day point in the AMPLE-2 study, for example, the incidence proportion of pleurodesis in patients with nontrapped vs trapped lungs was 28.8% vs 14.3% compared with 30.5% vs 28.6% at the 6-month follow-up.³

This article originally appeared on Pulmonology Advisor