1733P - Analysis of chemotherapy (Ct) efficacy according to histology in malignant pleural mesothelioma (MPM) patients (p)

Background

MPM is a highly aggressive pleural tumor with limited survival. CheckMate-743 trial demonstrated survival benefit of immunotherapy over Ct in 1^st line with some differences in the efficacy of Ct according to histology. However, randomized trials who led to the approval of antifolate in MPM did not include analysis of outcomes by histology. The objective of this study is to characterize the impact of Ct according to histology in p with MPM.

Methods

Clinical records of MPM diagnosed at Vall d´Hebron University Hospital between November 2002 and April 2020 were reviewed. Associations between clinical variables and outcome were assessed with Cox regression models and survival data were calculated by the Kaplan-Meier method.

Results

189 p were included. P’s characteristics: median age 68 years (y) (45-88 y), males: 70%, performance status (PS)1: 69%, epithelioid: 76%. First line Ct was offered to 85% of p (66% cisplatin and 27% carboplatin). Median overall survival (OS) was 21.3 m (95%CI17.2-24.3). Epithelioid histology, PS 0, and treatment with cisplatin vs carboplatin were associated with significant improvements in OS (p<0.001). Median PFS for p with epithelioid tumors treated with Ct in 1^st line was 4.8 m versus 3.6 months non-epithelioid (HR1.5 CI95% 1.1-2.3; p=0.03). OS of epithelioid p treated with 1^st line Ct was 26.7 m versus 15.0 m non-epithelioid patients (HR2.25 CI95% 1.4-3.4; p<0.001). The improvement of outcomes in patients with epithelioid histology was detected in patients treated with cisplatin or carboplatin. Histology was not a predictive factor for the platinum agent sensitivity (p of interaction PFS=0.09, p of interaction OS=0.65) (Table). Table: 1733P

Conclusions

In our series, patients with nonepithelioid tumors presented worse prognosis. Although epithelioid tumors exposed to cisplatin had higher PFS, histology was not a clear predictor of Ct efficacy.

Clinical trial identification

Editorial acknowledgement

Legal entity responsible for the study

The authors.

Funding

Has not received any funding.

Disclosure

S. Cedres: Financial Interests, Personal, Advisory Role: BMS; Financial Interests, Personal, Advisory Role: MSD; Financial Interests, Personal, Advisory Role: Boehringer Ingelheim; Financial Interests, Personal, Advisory Role: Amphera; Financial Interests, Personal, Advisory Role: Roche. P. Iranzo Gomez: Financial Interests, Personal, Advisory Role: BMS; Financial Interests, Personal, Advisory Role: Roche; Financial Interests, Personal, Advisory Role: MSD; Financial Interests, Personal, Advisory Role: Boehringer Ingelheim; Financial Interests, Personal, Advisory Role: Rovi; Financial Interests, Personal, Advisory Role: Kyowa. A. Callejo Perez: Financial Interests, Personal, Advisory Role: BMS; Financial Interests, Personal, Advisory Role: Roche; Financial Interests, Personal, Advisory Role: Pfizer; Financial Interests, Personal, Advisory Role: Boehringer Ingelheim; Financial Interests, Personal, Advisory Role: BMS; Financial Interests, Personal, Advisory Role: Kyowa. N. Pardo Aranda: Financial Interests, Personal, Advisory Role: BMS; Financial Interests, Personal, Advisory Role: Roche; Financial Interests, Personal, Advisory Role: Pfizer; Financial Interests, Personal, Advisory Role: Boehringer Ingelheim. A. Navarro: Financial Interests, Personal, Advisory Role: BMS; Financial Interests, Personal, Advisory Role: Roche; Financial Interests, Personal, Advisory Role: Pfizer; Financial Interests, Personal, Advisory Role: Boehringer Ingelheim; Financial Interests, Personal, Advisory Role: Oryzon. A. Martinez-Marti: Financial Interests, Personal, Advisory Role: BMS; Financial Interests, Personal, Advisory Role: Roche; Financial Interests, Personal, Advisory Role: Pfizer; Financial Interests, Personal, Advisory Role: Boehringer Ingelheim; Financial Interests, Personal, Advisory Role: MSD. E. Felip: Financial Interests, Personal, Advisory Role: AbbVie; Financial Interests, Personal, Advisory Role: AstraZeneca; Financial Interests, Personal, Advisory Role: BerGenBio; Financial Interests, Personal, Advisory Role: Beigene; Financial Interests, Personal, Advisory Role: Bayer; Financial Interests, Personal, Advisory Role: Blueprint; Financial Interests, Personal, Advisory Role: Boehringer Ingelheim; Financial Interests, Personal, Advisory Role: BMS; Financial Interests, Personal, Advisory Role: Eli Lilly; Financial Interests, Personal, Advisory Role: Glaxo; Financial Interests, Personal, Advisory Role: Guardant Health; Financial Interests, Personal, Advisory Role: Janssen; Financial Interests, Personal, Advisory Role: Medscape; Financial Interests, Personal, Advisory Role: MSD; Financial Interests, Personal, Advisory Role: Novartis; Financial Interests, Personal, Advisory Role: Pfizer; Financial Interests, Personal, Advisory Role: priME; Financial Interests, Personal, Advisory Role: Roche; Financial Interests, Personal, Advisory Role: Sanofi; Financial Interests, Personal, Advisory Role: Samsung; Financial Interests, Personal, Advisory Board: Grifols; Financial Interests, Personal, Advisory Role: Takeda. All other authors have declared no conflicts of interest.