Prognostication in malignant pleural effusion: One size does not fit all

Mortality after treatment of malignant pleural effusions with indwelling pleural catheters versus chemical pleurodesis: a population-based study

BACKGROUND

Little is known about patient outcomes following treatment of malignant pleural effusions (MPE) in the real-world setting.

RESEARCH QUESTION

We aimed to compare post-procedure all-cause mortality between individuals who received indwelling pleural catheter (IPC) insertion versus chemical pleurodesis for managing MPEs.

STUDY DESIGN AND METHODS

We performed a retrospective population-based study using provincial health administrative data (Ontario, Canada) of adults with a MPE who underwent IPC insertion or chemical pleurodesis between 2015 and 2019. Individuals were followed until death or March 31, 2021. Difference in post-procedure mortality was calculated using inverse probability of treatment weighting (IPTW)-adjusted Cox proportional hazard regression analysis to balance potential confounders at baseline.

RESULTS

We identified 4,790 (77.3%) individuals who received an IPC and 1,407 (22.7%) who had chemical pleurodesis for MPE. IPC insertions are increasing and chemical pleurodesis procedures are decreasing. The majority of IPCs were inserted in outpatients (61%), by pulmonologists (64.2%) and at sites with higher annual IPC volume, while chemical pleurodesis procedures were generally done by thoracic surgeons (74%) and at sites with higher annual pleurodesis volumes. In unadjusted comparison median time from initial cancer diagnosis to intervention was significantly longer in the IPC group (244 days, interquartile range [IQR]:33-903) compared to pleurodesis group (81 days, IQR:10-737; p < 0.0001). Unadjusted median time from index procedure to death was significantly longer in the pleurodesis group (165[IQR:48-457] days vs. 81[IQR:29-256] days, p < 0.0001), however the difference between groups became insignificant after the IPTW was applied (HR 1.27, 95%CI 0.95-1.69). 35% of IPCs were removed prior to death or end of follow-up.

INTERPRETATION

After adjusting for differences in baseline characteristics there was no difference in post-procedure mortality between IPC and chemical pleurodesis groups. In the real world, there are significant differences in the characteristics of patients who receive these two procedures and notable regional practice variation between procedure use. Future research should evaluate these variations in care and their effect on patient outcomes.

Aptamer-siRNA chimera and gold nanoparticle modified collagen membrane for the treatment of malignant pleural effusion

Malignant pleural effusion is one of the most common complications of advanced lung cancer and there is no effective clinical treatment at present. Here, we constructed an aptamer-siRNA chimeras/PEI/PEG/gold nanoparticle (AuNP)/collagen membrane that can progressively activate T cells by layer by layer assembly. Electron microscope showed this collagen membrane could be divided into 10 layers with a total thickness of 50–80μm, and AuNPs could be observed. Aptamer-siRNA chimeras could bind specifically to OX40⁺ cells and silencing programmed death receptor-1 (PD-1) gene. In vitro experiments demonstrated that chimeras/PEI/PEG/AuNPs gradually activated T cells to continuously kill lung adenocarcinoma cells in malignant pleural effusion. Animal experiments showed that chimeras/PEI/PEG/AuNP/collagen membrane effectively treated malignant pleural effusion. Compared with PD-1 inhibitor group, the number of cancer cells, ki-67 proliferation index and CD44 expression in the pleural effusion was significantly decreased and the lymphocyte/cancer cell ratio was significantly increased in the chimeras/AuNP-CM group. Flow cytometry showed that compared with PD-1 inhibitor group, T cell number in the chimeras/AuNP-CM group was significantly increased, while the proportion of PD-1⁺ T cells was markedly decreased. In conclusion, we constructed an chimeras/PEI/PEG/AuNP/collagen membrane, which was more effective in the treatment of malignant pleural effusion, and had less side effects than PD-1 inhibitors.

Evaluation of prognostication scores and proposal for refinement in malignant pleural effusion in Asians

BACKGROUND AND OBJECTIVE

Prognostication of malignant pleural effusion (MPE) guides treatment strategies but existing prognostication scores are yet to be validated in Asians. We aimed to evaluate the performance of these scores in an Asian population. A refined score was also proposed based on the impact of EGFR mutation on survival.

METHODS

Survival and clinical data of histocytologically-confirmed MPE patients from a Hong Kong hospital were analyzed with the LENT, modified-LENT, PROMISE and SELECT (converted from its original model) scores. A refinement of the LENT score for Asians was proposed by inclusion of EGFR status (EGFR-LENT), which was compared with the LENT score and validated in an independent patient cohort.

RESULTS

All prognostication scores performed well on risk stratification by Kaplan-Meier curve (log rank p < 0.0001) in 368 MPE patients except for LENT in low-risk group. C-statistics for LENT, modified LENT, PROMISE and SELECT in predicting 3-month mortality were 0.77, 0.80, 0.80 and 0.82, respectively. The proposed LENT score refinement (EGFR-LENT) improved stratification among low-risk patients; with a higher C-statistic (0.83) in 3-month mortality prediction than LENT (0.77, p = 0.0121), PROMISE (0.80, p = 0.3713), and SELECT (0.82, p = 0.7908) scores. Validation of EGFR-LENT in an independent cohort (124 patients) confirmed good performance in predicting 3-month mortality (C-statistic 0.87, vs 0.79 in LENT, p = 0.0444).

CONCLUSION

All existing scores had reasonable performance in prognosticating MPE, and LENT score refinement by inclusion of EGFR mutation status improved its performance among Asian MPE patients.