Sabato 27 ottobre 2012 - Pacini Editore

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The histological analysis of thoracoscopic biopsies is regarded as
the diagnostic reference (gold standard) for the diagnosis of PE
as it has been reported to have 100% specificity for malignancy
and over 94% diagnostic sensitivity.
However, biopsy is an invasive method which should be avoided
where possible. Soluble mesothelin-related peptide (SM) is an
FDA approved biomarker for diagnosing and monitoring MPM 3 .
The aim of our study was to analyse the serum and the PE levels
of SM in patients undergoing pleural biopsy, in order to assess the
SM contribution to the-non invasive diagnostic work-up of MPM.
Methods. We evaluated SM at the cut-off levels of 1.08 nM for
serum (as reported in kits book) and 9.30 nM for PE (as found in
our previous studies, ref. 4). Both specimens drawn at the same
time from 81 patients included 33 MPM, 29 benign lesions (Bng)
and 19 non-MPM pleural metastasis (Mts). SM levels were measured
by the “MesoMark” ELISA assay kit (Cis-Bio International
Gif/Yvette; France) according to manufacturers’ instructions. All
samples were tested in duplicate.
To effected immunohistochemistry, 5-µm thick paraffin sections
were mounted on slides and deparaffinized. We performed immunohistochemistry
using the PATHWAY kit by Benchmark XT
system (Ventana). Strong reactivity for calretinin and cytokeratin
5/6 associated with negative reactivity for carcinoembryonic
antigen (CEA), epithelial membrane antigen (EMA) and thyroid
transcription factor 1 (TTF1-1) are considered to be supportive of
the diagnosis of MPM.
All statistical analyses were performed using Stata (StataCorp.
Stata Statistical Software Release 11.2 Stata Corporation, College
Station, TX, 2007).
Results. Patients with MPM were found to have significantly
lower SM levels in serum (median 1.37 nM) as compared to PE
(median 28.20 nM). Both these SM levels were higher than the
levels found in specimens from patients with Mts (median 0.51
nM and 3.05 nM, respectively) or Bng (median 0.35 nM and 5.00
nM, respectively).
By ROC curve analysis, serum SM in MPM vs Mts yelded an
AUC of 67.2 (P < 0.020, Se = 57.6%, Sp = 73.7%) and MPM
vs Bng yielded an AUC of 74.3 (P-value < 0.001, Sp = 89.7%).
In contrast, SM in PE MPM vs Mts yelded an AUC of 80.5
(P < 0.001, Se = 78.8%, Sp = 78.9%) whereas MPM vs Bng
yielded an AUC of 81.0 (P-value < 0.001, Sp = 82.8%).
We found SM levels ≥ cut off in serum of 19/33 (57.6%) MPM patients,
in 3/29 (10.3%) of patients with Bng (DOR = 11.8, P-value
< 0.001) and in 5/19 (26.3%) of patients with Mts (DOR = 3.8,
P-value < 0.020). In contrast, PE showed SM levels ≥ cut off in
26/33 (78.8%) MPM, in 5/29 (17.2%) Bng (DOR = 17.8, P-value
< 0.001) and in 4/19 (21.1%) Mts (DOR = 13.9, P-value < 0.001).
Finally, in MPM the SM tests in serum and PE showed concordant
results in 22/33 (66.6%) patients (17 positive sera/PE; 5
negative sera/PE). In contrast, discordant results were found in
11/33 (33.4%) MPM (9 positive PE/negative sera; 2 negative PE/
positive sera).
Discussion. An increased level of SM in PE and/or serum can
help the diagnosis of MPM. Positive SM results would suggest
the need for further invasive investigations, such as thoracoscopy
and histology.
references
1 Borasio P, Berruti A, Billé A, et al. Malignant pleural mesothelioma:
clinicopathologic and survival characteristics in a consecutive series
of 394 patients. Eur J Cardiothorac Surg 2008;33:307-13.
2 Gennaro V, Ugolini D, Viarengo P, et al. Incidence of pleural
mesothelioma in Liguria Region, Italy (1996-2002). Eur J Cancer
2005;41:2709-14.
3 Robinson BW, Creaney J, Lake R, et al. Mesothelin-family proteins
and diagnosis of mesothelioma. Lancet 2003;362:1612-6.
4 Fedeli F, Canessa PA, Ferro P. et al. Detection of solubile mesothelinrelated
peptides as diagnostic markers of malignant pleural mesothelioma
effusions. USCAP 2012. Laboratory Investigation 2012;92(Suppl.
1):Abs n.362.
CONGRESSO aNNualE di aNatOmia patOlOGiCa SiapEC – iap • fiRENzE, 25-27 OttOBRE 2012
nuclear magnetic resonance (nMr)-based
catabolomic profiling of pleural effusions
F. Simonato1 , R. Cappellesso1 , P. Vanzani2 , M. Fassan1 , M. Pivato1 ,
A. Olivotto1 , M. Siri1 , L. Zennaro2 , A. Fassina1 1 Department of Medicine, DIMED, Surgical Pathology & Cytopathology
Unit; 2 Dept. of Biological Chemistry, University of Padova, Italy
Background. Lung cancer (LC) is the leading cause of cancer
death worldwide and Non Small Cell Lung Cancer (NSCLC) is
the main histopathological category (75-80%), including squamous
cell carcinoma (SCC), adenocarcinoma (AdC) and largecell
carcinoma subtypes (Califano et al., 2012). SCC and AdC
account respectively for 42% and 39% of the LC cases. Treatment
and prognosis depend on the histological type of cancer, the
stage, and patients’ Performance Status. The introduction of new
targeted chemotherapic drugs (i.e. tyrosine kinase or angiogenetic
inhibitors) mandatorily requires the exact definition of LC histotypes
(Carter and Giaccone, 2012).
Although often asymptomatic, AdC first presentation may be a
pleural effusion (PE) (Light RW, 2011). PE is an aberrant accumulation
of fluid between the two pleural layers; it can be sub-classified
in transudate and exudate based on the chemical composition
(protein, lactate dehydrogenase [LDH], albumin, amylase, pH,
and glucose). The low cell number and the small protein amount
characterize transudates, resulting from imbalances in hydrostatic
and oncotic forces across an intact mesothelial barrier (as in heart
failure or cirrhosis) On the other hand, exudates occur more frequently
in patients affected by pneumonia or malignancy. Changes
in metabolism result in modified metabolite composition (chemical
compounds which are the end products of cellular processes in
living organisms), and future efforts should be done to characterize
different metabolomic profiles as novel diagnostic tools.
Few studies investigated the NMR-based metabolomics (metabolites
composition) in fluids: i) in human maternal urine and blood
plasma to study new metabolites markers with predictive value
for prenatal disorders (Diaz SO, et al., 2011) ii) in urine of rats
that underwent partial hepatectomy to follow the liver regeneration
(Bollard et al., 2010).
Material and methods. In this work we investigated the metabolic
profiling of PE by using Nuclear Magnetic Resonance (NMR), in
order to identify significant metabolic biomarkers able to discriminate
between AdC PE and non neoplastic PE. Unlike other spectrometric
techniques (as mass spectrometry), NMR can quantify
compounds in mixtures, as well as to identify unknown metabolites.
Results. We collected 40 PE samples from heart failure transudates
and 40 samples from AdC exudates. We added an additional
buffering at pH 7.4 to the specimens in order to normalize
the samples at a same pH. 1H NMR spectra were recorded at both
300MHz and 600MHz, on a Bruker Avance III spectrometer
equipped with a Z gradient unit, and processed with Topspin
software (v. 3.1).
Acquisition of the NMR spectra was carried out to verify eventual
intra- and inter- individual variations in metabolic profiles
of AdC and non-neoplastic PEs and identified new molecular
biomarkers.
references
Bollard ME, Contel NR, Ebbels TM, et al. NMR-based metabolic profiling
identifies biomarkers of liver regeneration following partial hepatectomy
in the rat, J Proteome Res 2010;9:59-69.
Califano R, Abidin AZ, Peck R, et al. Management of small cell lung
cancer: recent developments for optimal care, Drugs. 2012;72:471-90.
Carter CA, Giaccone G. Treatment of nonsmall cell lung cancer: overcoming
the resistance to epidermal growth factor receptor inhibitors.
Curr Opin Oncol 2012;24:123-9.
Diaz SO, Pinto J, Graça G, et al. Metabolic biomarkers of prenatal disorders:
an exploratory NMR metabonomics study of second trimester
maternal urine and blood plasma. J Proteome Res 2011;10:3732-42.
Light RW. Pleural effusions. Med Clin North Am 2011;95:1055-70.