Detection of Soluble Mesothelin in Serum and Pleural Effusion of Malignant Pleural Mesothelioma: A Contribution to Cytology
Franco Fedeli, Pier Aldo Canessa, Paola Ferro, Enrico Battolla, Paolo Dessanti, Antonella Vigani, Luigi Chiaffi, Maria Cristiana Franceschini, Vincenzo Fontana, Bartolomeo Bacigalupo, Maria Pia Pistillo, Silvio Roncella. ASL5, La Spezia, Italy; ASL5, Sarzana (SP), Italy; IRCCS A.O.U., San Martino-IST, Genova, Italy; AIL, La Spezia, Italy
Background: Soluble mesothelin (SM) is an FDA approved biomarker for diagnosing and monitoring MPM. It has been reported that the sensitivity of cytology (Cyt) for the diagnosis of MPM pleural effusions (PE) is about 30%. In this study we assessed the contribution that SM detection in serum and PE can give to improve the diagnosis and the routine screening of MPM in addition to Cyt.
Design: PE was obtained by thoracentesis and Cyt was evaluated on fixed smears stained by Papanicolaou's method in a total of 102 patients. Cyt, PE-SM and serum-SM levels were simultaneously evaluated for each patient. We studied 43 patients with MPM (26 epithelioid (Ept), 9 sarcomatoid (Src), 4 biphasic (Bph), 2 desmoplastic (Dsm), 2 papillary (Ppl)), 36 patients with pleural benign lesions (BNG) and 23 patients with non-MPM pleural metastasis (MTS). SM levels were detected by the MesoMark ELISA kit.
Results: By the Youden's index we found that the SM cut-off level for diagnosis of MPM was 1.08 nM in serum and 12.70 nM in PE. Serum-SM levels were > cut off in 20/43 (Se=46.5%) MPM (11 Ept, 4 Src, 4 Bph, 1 Ppl), in 3/36 (8.3%) BNG and in 6/23 (26.1%) MTS, (Sp=84.7). In contrast, PE-SM levels were > cut off in 30/43 (Se=69.8%) MPM (19 Ept, 5 Src, 2 Ppl, 4 Bph), in 3/36 (8.3%) BNG and in 4/23 (17.4%) MTS, (Sp=88.1%). Cyt allowed the diagnosis in 11/43 (Se=25.6%) cases of MPM (6 Ept, 3 Src, 1 Bph, 1 Ppl) and in 11/23 (47.8%) MTS while it was negative in 36/36 (100%) BNG. Comparison between serum-SM and Cyt demonstrated discrepancy for diagnosis in 41/102 (40.2%) cases. The serum-SM pos/Cyt neg cases were: 16/43 (37.2%) MPM (8 Ept, 4 Src, 3 Bph, 1 Ppl), 3/36 (8.3%) BNG and 5/23 (21.7%) MTS. In contrast, the serum-SM neg/Cyt pos cases were: 7/43 (16.3%) MPM (3 Ept, 3 Src, 1 Ppl,), 0/36 (0.0%) BNG and 10/23 (43.5%) MTS. Comparison between PE-SM and Cyt demonstrated discrepancy for diagnosis in 43/102 (42.2%) cases. The PE-SM pos/Cyt neg cases were: 23/43 (53.5%) MPM (15 Ept, 4 Src, 3 Bph, 1 Ppl), 3/36 (8.3%) BNG and 3/23 (13.0%) MTS. The PE-SM neg/Cyt pos cases were: 4/43 (9.3%) MPM (2 Ept, 2 Src), 0/36 (0.0%) BNG and 10/23 (43.5%) MTS.
Conclusions: SM detection may be an adjunct to Cyt for the routine screening of PE in MPM but it cannot replace it. Our data also suggest that detection of SM in PE can contribute to improve the diagnosis of Cyt in MPM more than detection of SM in serum.
Wednesday, March 6, 2013 1:00 PM
Poster Session VI # 286, Wednesday Afternoon