Patterns of comorbidity, treatment, resource utilization, and referral in malignant pleural mesothelioma patients in the US.

Abstract

8554 Background: Malignant pleural mesothelioma (MPM) is a rare but aggressive cancer, which may be challenging to diagnose. The standard of care for MPM is cisplatin plus pemetrexed. In the recent phase III MAPS trial, addition of bevacizumab provided a significant survival benefit. There is limited data on real-world MPM treatment patterns to provide context to trial results. Consequently, the present study was conducted to evaluate treatment and referral patterns, co-morbidities and resource use in patients with MPM in the U.S. Methods: Patients ≥18 years old with a diagnosis of MPM between Jan 2004 and September 2015 were identified from the MarketScan claims database. Patients were required to have data for 12 months prior, and at least 3 months post, the diagnosis index date. Patients with other (non-MPM) cancers, malignant mesothelioma of non-pleural origin and those enrolled in clinical trials were excluded from the analysis. Treatment and resource utilization were identified by their corresponding HCPCS and DRG codes. Referral patterns were estimated starting from the first lung-related visit during the year preceding MPM diagnosis. Results: In the cohort of 1,869 patients, the median age was 71 years (range 61–79) and 65% were male. 4.1% of patients underwent radical surgery and of the remaining 96%, 15.6% had first-line chemotherapy, 33.2% had first-line chemotherapy plus radiotherapy, 11.7% received radiotherapy, and 39.5% received no chemotherapy or radiotherapy. The most common diagnosis on the first lung-related visit was pleural effusion (16.5%), followed by chest pain (10.7%), shortness of breath (9.6%) and cough (8.5%). The median time from first lung-related visit to MPM diagnosis was 77 days (mean 134 days, IQR 23–258). Conclusions: This real-world analysis showed that only a small proportion of MPM patients (~4%) received radical surgery and a large number of patients did not receive any treatment at all, indicating a large unmet need for effective treatments in this disease area. Additionally, the pathway to MPM diagnosis may be challenging in this population with a poor prognosis, often involving multiple healthcare contacts over an extended period of time.