Radical pleurectomy and chemoradiation for malignant pleural mesothelioma: the outcome of incomplete resections.

BACKGROUND: The type of surgery (radical pleurectomy (RP) vs. extrapleural pneumonectomy (EPP)) remains controversial for malignant pleural mesothelioma (MPM). Macroscopic complete resection (MCR) is a key prognostic factor. It is unclear, if patients undergoing incomplete RP within a standardized multimodality treatment protocols have any advantage in terms of survival and if EPP could theoretically have avoided incomplete resections (R2).

METHODS: Eighty-eight patients underwent RP followed by chemoradiation from 2002 to 2011 within a prospective multimodality treatment study at a single institution. MCR were compared to R2 within this patient cohort retrospectively. EPP eligibility was assessed retrospectively based on preoperative cardiopulmonary testing and theoretical feasibility to achieve MCR. Kaplan-Meier analyses, log-rank test and Cox regression analyses were used to estimate survival and to determine predictors of survival.

RESULTS: For the complete patient cohort, median survival (MS) was 26.3 months (mo). MCR could be achieved in 64.8% (57/88). Compared to MCR patients, R2-patients (n = 31, 35.2%) had an inferior overall survival (MS 13 vs. 33 mo, P < .0001), shorter progression-free-survival (MS 9 vs. 16 mo, P < .0001) and inferior survival after disease progression (MS 4 vs. 11 mo; P < .0001), respectively. R2 was associated with advanced p-T-Status (P < .0001), p-N-Status (P = 0.046) and p-IMIG stage (P < .0001). No difference could be observed with regard to age, histology, laterality, surgical morbidity and mortality, respectively. Only 3 out of 88 patients (3.4%) would have been eligible for EPP to achieve MCR. Not resectable T4-disease and impaired cardiopulmonary reserves were the main reasons for ineligibility for EPP in 35.5% (11/31) and 48.4% (15/31), respectively.

CONCLUSIONS: R2 in patients undergoing RP is associated with inferior outcomes. Only very selected cases would have qualified for EPP to achieve MCR. EPP might be an important surgical extension in selected patients to achieve MCR. There is a need for further investigation of effective intrapleural additive treatment options for patients undergoing R2.