Background: Malignant pleural effusion (MPE) is associated with disabling dyspnoea and poor survival. Current guidelines recommend initial pleural aspiration to provide a diagnosis and alleviate dyspnoea. However, patients may undergo multiple procedures because pleural aspiration often fails to provide actionable histocytology and definitive control of dyspnoea. No studies to date have assessed the burden of this pathway in Australia.

Aims: Quantify the procedural burden patients with MPE undergo and time to actionable histocytology.

Methods: Retrospective analysis of all patients diagnosed with MPE at two tertiary centers and one regional center in Australia over 12 months. Data collected included initial cytology, time to deliver actionable histocytology and definitive pleural intervention, overall procedural burden, and survival.

Results: 103 patients were diagnosed with MPE (14 tumour types). 50/102 (49%) patients had initial negative fluid cytology. The remainder of cases with initial positive fluid cytology, 27/102 (26.5%) had adequate sample to guide management. Patients underwent a median of 2 pleural procedures with 57/103 (55.3%) undergoing more than 1 pleural procedure. Average interval from referral to diagnosis was 32 days, with an additional delay of 13 days to actionable histocytology. 61/103 (59.2%) had definitive pleural intervention with average interval of 34 days from referral. Median survival was 110 days.

Conclusions: Patients with MPE frequently undergo multiple pleural procedures and experience considerable delays to diagnosis in Australia. Development of streamlined pathways to optimize treatment access and minimize procedural burden is urgently needed.