Poster Presentation Clinical Oncology Society of Australia Annual Scientific Meeting 2022

Real-world outcomes for patients with pleural mesothelioma: a multisite retrospective cohort study. (#275)

Kar Ven Cavan KVCC Chow 1 2 , Cassie CT Turner 1 2 3 , Brett BH Hughes 2 3 4 , Kathleen KH Houston 1 5 , Zarnie ZL Lwin 2 3 4 , Bryan BC Chan 1 2 5
  1. The Adem Crosby Centre, Medical Oncology, Sunshine Coast Hospital and Health Service, Birtinya, Queensland, Australia
  2. School of Medicine, The University of Queensland, Brisbane, Queensland, Australia
  3. Department of Medical Oncology, Royal Brisbane and Women's Hospital, Brisbane, Queensland, Australia
  4. Department of Medical Oncology, The Prince Charles Hospital, Chermside, Queensland, Australia
  5. School of Medicine and Dentistry, Griffith University, Gold Coast, Queensland, Australia

Aim:

To evaluate the real-world treatment patterns and outcomes for patients with pleural mesothelioma (PM), particularly in the era of immunotherapy.

 

Methods:

This retrospective audit included patients with PM diagnosed within the Sunshine Coast and Metro North Health Services (Queensland) from January 2017 to August 2022.  Patient and treatment characteristics and outcomes were recorded.  Data was analysed using descriptive statistics and Kaplan Meier survival method. 

 

Results:

Of 102 patients, 82% were male with a median age of 73 years (range 48-91) and 86% had baseline ECOG of 0-1. Subtypes included: epithelioid (61%), biphasic (14%), sarcomatoid (12%), or unspecified/unknown (14%). Surgical interventions included: pleurectomy/decortication (2%) and VATS pleurodesis (35%). First-line systemic treatment included: platinum/pemetrexed (39%), ipilimumab and nivolumab (17%), durvalumab and chemotherapy on trial (13%), pembrolizumab (1%), clinical trial (2%), and 28% had best supportive care (BSC). 12-month overall survival (OS) and progression-free survival rates were 58% (95% CI: 49-69) and 30% (95% CI 20-44) respectively. By subtype, 12-month OS rates were 67% (95% CI: 55-80) for epithelioid, 62% (95% CI: 41-95) for biphasic and 37% (95% CI: 17-80) for sarcomatoid PM. There was a trend toward improved OS with first-line immunotherapy (doublet or with chemotherapy) over chemotherapy alone (HR 0.54, 95% CI: 0.27-1.08, p=0.068). 12-month OS rates were 84% (95% CI: 66-100) for ipilimumab and nivolumab, 83% (95% CI: 64-100) for durvalumab and chemotherapy, 65% (95% CI: 51-81) for chemotherapy alone, and 26% (95% CI: 14-49) for BSC.

 

Conclusion:

In our unselected real-world population, a significant proportion of patients with PM did not receive active therapy and whilst immunotherapy has broadened treatment options (PBS July 2021), here it did not significantly improve OS compared to chemotherapy. Optimising suitability for therapy and trials is critical to meaningfully improve real-world survival for PM.