Malignant pleural mesothelioma: clinicopathologic and survival characteristics in a consecutive series of 394 patients.

OBJECTIVE

Treatment of malignant pleural mesothelioma (MPM) remains disappointing, although recent reports suggest that multimodality therapy including surgery may provide a significant survival benefit. The aims of this single institution study were: to investigate clinicopathologic characteristics and potential prognostic factors in MPM patients, and to ascertain whether surgery followed by adjuvant therapy had an independent prognostic role.

METHODS

Retrospective review of a prospectively compiled computerized database of all patients with MPM evaluated between 1989 and 2003. Kaplan-Meier method, log-rank test, and Cox model were used in the statistical analysis.

RESULTS

There were 394 patients: 270 men (68.5%), 124 women, median age 64 (range 28-93). Twenty-seven patients (6.8%) underwent surgical resection (extrapleural pneumonectomy 15, pleurectomy/decortication 12), followed by adjuvant therapy. As of March 2006, 381 patients (96.7%) had died (median survival, 11.7 months; range 0.03-117.9). Median follow-up of 13 surviving patients (3.3%) was 45.2 months (range 28.7-126.5). Overall survival at 2 years was 18.8%. Multimodality therapy including surgery yielded a median survival of 14.5 months and a 2-year survival rate of 29.6%. Using univariate analysis, age (p=0.009), chest pain (p=0.01), weight loss (p=0.001), performance status (p=0.0001), platelet count (p=0.008), histology (p=0.0001), macroscopic appearance of pleural surface (non-specific inflammation, tumor-like thickening, or nodules; p=0.0001), visceral pleura involvement (p=0.0001), degree of involvement of pleural cavity (less than or more than one third of the cavity; p=0.0001), and multimodality therapy (p<0.01) were found to be significant prognostic factors. At multivariate analysis, performance status, platelet count, histology, and degree of involvement of pleural cavity remained independently associated with survival, whereas multimodality therapy failed to enter the model.

CONCLUSIONS

Significant predictors of survival include performance status, platelet count, histology, and degree of involvement of pleural cavity. Within the confines of this retrospective study and the small number of patients undergoing multimodality therapy, the role of surgery in the treatment of MPM remains unclear. Further investigation is warranted to determine the optimal treatment strategy in this disease.