e18509 Background: The prognostic systems currently in use in MPM, such as the EORTC and CALGB score, include the clinical and histological parameters, excluding the FDG-PET (PET) evaluation and the possibility of surgery. The aim of our study was to investigate the role of PET baseline SUV-max and surgery as prognostic factors in MPM. Methods: From April 2002to December 2012, 48 pts with a certain histological diagnosis of MPM underwent staging by PET scan before peri-operative (multimodality treatment) or palliative first-line chemotherapy (CT). Surgery was performed in 22(45.8%) pts. Pt characteristics: males 44(91.7%), females 4(8.3%); median age 65 (51-77) years; ECOG PS 0-1 45(93.7 %), PS 2 3(6.3 %); IMIG stage I-II 18(37.5%), III-IV 30(62.5%); histological subtype epithelial 40(83.3%), mixed 5(10.4%), sarcomatoid 3(6.3%); extrapleural pneumonectomy 8(16.8%), pleurectomy/decortication 14(29.2%), 17 (35.4%) VATS plus pleurodesis, 19(39.6%) no surgical procedures. Platinum based CT was performed in combination with pemetrexed in 39(81.3%) pts and with gemcitabine in 9(18.7%). According to the EORTC score 30(62.5%) pts were classified in the good prognosis group and 18(37.5%) as poor prognosis. The cut-off value of PET baseline SUV-max calculated by ROC analysis was 9; SUV-max at baseline PET was ≤ 9 in 32(66.7%) pts and >9 in 16(33.3%). Median overall survival (OS) was 12 (3-60) months. Results: Upon validating the impact of individual factors on OS using the Kaplan-Meier analysis, we found statistical significance was reached by histology (p=0.0038) and surgery (p=0.0027). In a multivariate analysis using the Cox regression system, considering OS as a dependent variable, according to age, histology, stage, PET baseline SUV-max and surgery, epithelial histology (p =0.002) and surgery (p=0.012) achieved a statistical significance. SUV-max at baseline PET was not statistically significant (p = 0.290), excluding it as a possible independent prognostic factor in MPM. Conclusions: This analysis does not indicate any prognostic value for baseline PET in MPM, confirming the importance of histological subtype and introducing surgery as a possible prognostic factor.
Histologic Assessment and Prognostic Factors of Malignant Pleural Mesothelioma Treated With Extrapleural Pneumonectomy
