Characteristics of long-term survivors with malignant pleural mesothelioma.

Background: Pleural mesothelioma (PM) is a cancer with usually a dismal prognosis. However, long-term survivors do exist. Herein, we analyzed long-term survivors (>5 years after surgery) from high-volume centres around the world.

Methods: This is a multicenter retrospective descriptive analysis of long-term survivors (overall survival ≥ 5 years from surgery) treated within a multimodality therapy approach including macroscopic complete resection. Overall survival was calculated with Kaplan Meier analysis and cases were matched by center and surgery year and compared with a control group of short-term survivors (<2 years) in a conditional logistic regression analysis.

Results: There were 276 long-term survivors, most were male (n=166, 63%) with a median age of 59 (range 21-83) years at time of diagnosis. The histology for 246 was epithelioid and non-epithelioid for 30 patients. The disease was on the right side in 58% of the patients. As of this analysis, 148 patients were dead, 104 were alive and 10 were lost to follow-up. Pathological tumor stages were: pT1 (n=50), pT2 (n=63), pT3 (n=90) or pT4 (n=16), pN0 (n=150), pN1 (n=20) and pN2 (n=39). The matched control dataset included 333 patients, 95 cases and 238 controls. Comparing short- with long-term survivors, there was moderate evidence that a low white blood cell (WBC) count before surgery was more often observed in long-term survivors.

Conclusions: The data show that long-term survival in PM is possible in a subgroup of surgically treated patients; histological subtype and WBC count seem to be prognosticators for longer survival.