[Show abstract][Hide abstract] ABSTRACT: Breath analysis for the purpose of non-invasive diagnosis of lung cancer has yielded numerous candidate compounds with still questionable clinical relevance. To arrive at suitable volatile organic compounds our approach combined the analysis of different sources: isolated tumor samples compared to healthy lung tissues, and exhaled breath from lung cancer patients and healthy controls. Candidate compounds were further compared to substances previously identified in the comparison of transformed and normal lung epithelial cell lines. For human studies, a breath sampling device was developed enabling automated and CO2-controlled collection of the end-tidal air. All samples were first preconcentrated on multibed sorption tubes and analyzed with gas chromatography mass spectrometry (GC-MS). Significantly (p < 0.05) higher concentrations in all three types of cancer samples studied were observed for ethanol and n-octane. Additional metabolites (inter alia 2-methylpentane, n-hexane) significantly released by lung cancer cells were observed at higher levels in cancer lung tissues and breath samples (compared to respective healthy controls) with statistical significance (p < 0.05) only in breath samples. The results obtained confirmed the cancer-related origin of volatile metabolites, e.g. ethanol and octane that were both detected at significantly (p < 0.05) elevated concentrations in all three kinds of cancer samples studied. This work is an important step towards identification of volatile breath markers of lung cancer through the demonstration of cancer-related origin of certain volatile metabolites.
Journal of Breath Research 05/2014; 8(2):027111. · 2.57 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background
Regulatory T cells (Treg) are critical for cancer immune evasion; whereas natural killer (NK) cells are central for effective anti-tumor immunity including antibody-induced cellular cytotoxicity (ADCC). The predictive role of Treg levels for clinical response to chemo-immunotherapy in non-small cell lung cancer (NSCLC) as well as therapy-induced Treg changes remain to be defined.
Patients and Methods
The impact of Treg on NK-mediated cetuximab-dependent cellular cytoxicity was tested in vitro. Frequency and functional activity of Treg was analyzed in 31 NSCLC stage IB-IIIA patients treated by neoadjuvant Cetuximab/Docetaxel/Cisplatin prior to surgery. Data were correlated with clinical outcome variables and Treg tumor infiltration.
Treg potently inhibit NK-mediated and cetuximab-induced ADCC in vitro. In addition, a significant correlation between Treg reduction and clinical response was seen. However, the grade of tumor infiltrating Treg in resected tumors did not correlate with peripheral Treg levels. Moreover, Treg levels at diagnosis did not predict clinical response to chemo-immunotherapy.
The drop of Treg levels during neoadjuvant chemo-immunotherapy in NSCLC patients significantly correlates with clinical response. However, Treg at diagnosis are not linked to inferior clinical response to chemo-immune therapy in NSCLC in vivo even though Treg efficiently inhibit ADCC in vitro.
Lung cancer (Amsterdam, Netherlands) 01/2014; · 3.14 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background
It is not clear whether or not the fate of patients suffering from small-cell lung cancer (SCLC) has improved. To better understand the course of disease, we aimed at documenting disease features at initial diagnosis, sequences of therapy modalities and outcome in consecutive patients over two decades. We postulated that SCLC patients might have benefitted from refined diagnosis and treatment options during the last decade.
All SCLC cases diagnosed at the Innsbruck University Hospital and associated institutions between 1991–2011 have been documented in detail in accordance with a prespecified protocol.
A total of 484 patients diagnosed with SCLC were followed. The most important symptoms at initial diagnosis were weight loss, cough and dyspnea in 66%, 55% and 51% of patients, respectively. Patients who were operated during early stage of disease (n = 26) had a favourable five-year, relapse-free survival (74%). 112 patients with locally advanced disease were treated by radiochemotherapy in curative intent (RCT), and achievement of CR offered a chance of long term overall survival (OS), reaching 20% after 10-years. In the palliative setting (median OS in 304 evaluable patients, 9.4 months), a therapeutic progress in the more recent decade could not be observed. Parameters independently associated with favourable OS were response to therapy and prophylactic brain irradiation in patients with RCT, and response, age <70 years and absence of LDH elevation in the palliative setting.
In this comprehensive view on SCLC, the findings on symptomatology, comorbidity, and spectrum of treatments may help to better understand individual courses of the disease. Overall, modern medicine failed to translate into substantial benefit of SCLC patients, except in patients in locally advanced disease receiving multimodal therapy
Lung cancer (Amsterdam, Netherlands) 01/2014; · 3.14 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Non-invasive disease monitoring on the basis of volatile breath markers is a very attractive but challenging task. Several hundreds of compounds have been detected in exhaled air using modern analytical techniques (e.g. proton-transfer reaction mass spectrometry, gas chromatography-mass spectrometry) and have even been linked to various diseases. However, the biochemical background for most of compounds detected in breath samples has not been elucidated; therefore, the obtained results should be interpreted with care to avoid false correlations. The major aim of this study was to assess the effects of smoking on the composition of exhaled breath. Additionally, the potential origin of breath volatile organic compounds (VOCs) is discussed focusing on diet, environmental exposure and biological pathways based on other's studies. Profiles of VOCs detected in exhaled breath and inspired air samples of 115 subjects with addition of urine headspace derived from 50 volunteers are presented. Samples were analyzed with GC-MS after preconcentration on multibed sorption tubes in case of breath samples and solid phase micro-extraction (SPME) in the case of urine samples. Altogether 266 compounds were found in exhaled breath of at least 10% of the volunteers. From these, 162 compounds were identified by spectral library match and retention time (based on reference standards). It is shown that the composition of exhaled breath is considerably influenced by exposure to pollution and indoor-air contaminants and particularly by smoking. More than 80 organic compounds were found to be significantly related to smoking, the largest group comprising unsaturated hydrocarbons (29 dienes, 27 alkenes and 3 alkynes). On the basis of the presented results, we suggest that for the future understanding of breath data it will be necessary to carefully investigate the potential biological origin of volatiles, e.g., by means of analysis of tissues, isolated cell lines or other body fluids. In particular, VOCs linked to smoking habit or being the results of human exposure should be considered with care for clinical diagnosis since small changes in their concentration profiles (typically in the ppt(v)-ppb(v) range) revealing that the outbreak of certain disease might be hampered by already high background.
Journal of Breath Research 08/2012; 6(3):036008. · 2.57 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Isoprene (2-methylbuta-1,3-diene) represents a precursor molecule of isoprenoids (steroids, terpens), and available data suggest that isoprene is related to cholesterol biosynthesis. Breath concentrations of isoprene have been reported to be altered in a number of clinical conditions. However, the physiological meaning of isoprene changes has not yet been established. Utilizing proton-transfer-mass spectroscopy, we analyzed isoprene concentrations (m/z 69, tentatively identified as isoprene) in breath samples in Tedlar bags collected from 79 lung cancer patients (23 females, 56 males). Results were compared to the concentrations of immune activation marker neopterin (ELISA, BRAHMS, Hennigsdorf, Germany), lipid parameters (routine enzymology) and C-reactive protein (CRP). Isoprene concentrations were median 92.5 ppb (25th-75th percentile: 79-131 ppb). There was no relationship with staging, grading or age, but isoprene concentrations correlated significantly with total cholesterol (rs = 0.281, p < 0.01) and LDL cholesterol (rs = 0.236, p < 0.05). There was no significant relationship between exhaled isoprene concentrations and HDL cholesterol (rs = 0.048), triglycerides (rs = 0.164) and CRP (rs = -0.115; all not significant). A significant inverse correlation existed between isoprene and neopterin concentrations (rs = -0.215, p < 0.05); the latter also correlated with total cholesterol (rs = -0.343, p = 0.001), HDL cholesterol (rs = -0.273, p = 0.01), LDL cholesterol (rs = -0.236, p < 0.05) and CRP (rs = 0.230, p < 0.05) but not with triglycerides (rs = 0.035, not significant). Results suggest that immune activation might play a role in the decline of isoprene which is probably related to lipid metabolic changes. Interestingly, similar relationships between elevated neopterin and decreased lipid concentrations have been reported earlier in other clinical conditions, e.g. in patients with HIV-1 infection.
Journal of Breath Research 03/2012; 6(2):027101. · 2.57 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: In epidermal growth factor receptor (EGFR)-mutated non-small cell lung cancer (NSCLC), the tyrosine-kinase inhibitor gefitinib is in broad use. We retrospectively analysed data for 82 patients with advanced NSCLC treated with gefitinib and correlated benefits with clinical baseline and therapy-related parameters.
Of all patients 48/82 were male; the median age at start of gefitinib was 67.2 years; 14/58 informative patients were never-smokers; 57/82 patients suffered from adenocarcinoma, including 7 with bronchoalveolar-carcinomas.
As to be expected, partial remission was observed in 10% of patients, stable disease in 29%, progression-free survival was 3.1 months and overall survival 9.2 months. Gefitinib was more efficacious in women, never-smokers and patients with bronchoalveolar-carcinoma. Furthermore, anemia and elevated C-reactive protein levels were unfavourable for therapeutic efficacy. Patients developing skin reactions under gefitinib achieved response far more frequently, with longer progression-free survival and overall survival.
Basic clinical parameters are good predictors for response to EGFR tyrosine-kinase inhibitor therapy, which may be of value if EGFR mutation status is not available.
Anticancer research 09/2011; 31(9):2949-55. · 1.71 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The tumor microenvironment comprises various cellular components and associated subcellular molecules with antitumor and protumor effects. Because respective targeted treatment strategies are arising, it is important to characterize the exact role of these parameters. This study provides a comprehensive analysis of key immunologic factors in the tumor microenvironment of 383 surgically resected non-small cell lung cancer specimens. CD4, CD8, forkhead box protein P3, transforming growth factor β, Casitas B-cell lymphoma-b, programed death 1, T-cell-restricted intracellular antigen 1, granzyme B, mast cell tryptase, and stromal cell-derived factor 1 were analyzed by immunohistochemistry using a standardized tissue microarray platform. Extensive clinical data enabled detailed clinicopathologic correlations over a postoperative follow-up period of 15 years. Among the immunologic variables focused on, transforming growth factor β expression was the only prognostically relevant factor. Transforming growth factor β was more frequently expressed in adenocarcinoma as compared with other histologic subtypes. Expression of transforming growth factor β in tumor-infiltrating lymphocytes or in tumor cells was associated with significantly reduced postoperative survival time especially in patients with squamous cell carcinoma (P = .035 and P = .046, respectively). In these patients, the amount of transforming growth factor β-positive tumor-infiltrating lymphocytes represented the only independent immunologic parameter with prognostic significance by multivariat analysis (P = .021; hazard ratio, 2.602; 95% confidence interval, 1.159-5.844). These results should help to identify patients who are most suitable for therapeutic strategies aiming to block the transforming growth factor β signaling pathway.
Human pathology 08/2011; 43(3):339-49. · 3.03 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A large group of interacting molecular factors, involved in epithelial-mesenchymal transition, epidermal growth factor receptor (EGFR) signaling, and G1 mitotic phase, are shown to play an important role in cancerogenesis and progression of non-small cell lung cancer (NSCLC). Since success concerning potential correlations, structural and numeric gene aberrations, and biological risk assessment of these molecular factors are still lacking, combined analysis of a multitude of intertwined factors is currently a promising approach.
Cyclins (D1, D2, D3, and E), p21, p27, EGFR, Snail, E-cadherin, beta-catenin, phosphatidylinositol-3' kinase, phosphatase and tensin homologue, phosphorylated Akt, and phosphorylated signal transducer, and activator of transcription-3 were analyzed by immunohistochemistry in 405 surgically resected NSCLC, using a standardized tissue microarray platform. In addition, the gene status of EGFR and cyclin D1 was examined by fluorescence in situ hybridization. Extensive clinical data were acquired, enabling detailed clinicopathologic correlation during a postoperative follow-up period of up to 14 years.
The protein overexpressions of nuclear p27, cyclin D1, cyclin D3, E-cadherin, and EGFR as assessed by immunohistochemistry were all associated with a significant reduction in overall survival time. In addition, cyclin D1 proved especially important, being the only independent molecular tumor-related factor with prognostic significance by multivariable analysis. In analogy to EGFR, recurrent numeric gene aberrations, particularly high-level amplifications, of cyclin D1 were obvious.
The results emphasize that deregulation of controlling factors of the early G1 phase is of significant oncogenic relevance and may represent a potential treatment target in NSCLC.
Journal of thoracic oncology: official publication of the International Association for the Study of Lung Cancer 09/2010; 5(9):1325-36. · 4.55 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Lung cancer is one of the leading causes of death in Europe and the western world. At present, diagnosis of lung cancer very often happens late in the course of the disease since inexpensive, non-invasive and sufficiently sensitive and specific screening methods are not available. Even though the CT diagnostic methods are good, it must be assured that "screening benefit outweighs risk, across all individuals screened, not only those with lung cancer". An early non-invasive diagnosis of lung cancer would improve prognosis and enlarge treatment options. Analysis of exhaled breath would be an ideal diagnostic method, since it is non-invasive and totally painless.
Exhaled breath and inhaled room air samples were analyzed using proton transfer reaction mass spectrometry (PTR-MS) and solid phase microextraction with subsequent gas chromatography mass spectrometry (SPME-GCMS). For the PTR-MS measurements, 220 lung cancer patients and 441 healthy volunteers were recruited. For the GCMS measurements, we collected samples from 65 lung cancer patients and 31 healthy volunteers. Lung cancer patients were in different disease stages and under treatment with different regimes. Mixed expiratory and indoor air samples were collected in Tedlar bags, and either analyzed directly by PTR-MS or transferred to glass vials and analyzed by gas chromatography mass spectrometry (GCMS). Only those measurements of compounds were considered, which showed at least a 15% higher concentration in exhaled breath than in indoor air. Compounds related to smoking behavior such as acetonitrile and benzene were not used to differentiate between lung cancer patients and healthy volunteers.
Isoprene, acetone and methanol are compounds appearing in everybody's exhaled breath. These three main compounds of exhaled breath show slightly lower concentrations in lung cancer patients as compared to healthy volunteers (p < 0.01 for isoprene and acetone, p = 0.011 for methanol; PTR-MS measurements). A comparison of the GCMS-results of 65 lung cancer patients with those of 31 healthy volunteers revealed differences in concentration for more than 50 compounds. Sensitivity for detection of lung cancer patients based on presence of (one of) 4 different compounds not arising in exhaled breath of healthy volunteers was 52% with a specificity of 100%. Using 15 (or 21) different compounds for distinction, sensitivity was 71% (80%) with a specificity of 100%. Potential marker compounds are alcohols, aldehydes, ketones and hydrocarbons.
GCMS-SPME is a relatively insensitive method. Hence compounds not appearing in exhaled breath of healthy volunteers may be below the limit of detection (LOD). PTR-MS, on the other hand, does not need preconcentration and gives much more reliable quantitative results then GCMS-SPME. The shortcoming of PTR-MS is that it cannot identify compounds with certainty. Hence SPME-GCMS and PTR-MS complement each other, each method having its particular advantages and disadvantages. Exhaled breath analysis is promising to become a future non-invasive lung cancer screening method. In order to proceed towards this goal, precise identification of compounds observed in exhaled breath of lung cancer patients is necessary. Comparison with compounds released from lung cancer cell cultures, and additional information on exhaled breath composition in other cancer forms will be important.
[Show abstract][Hide abstract] ABSTRACT: Analysis of exhaled breath is a promising diagnostic method. Sampling of exhaled breath is non-invasive and can be performed as often as considered desirable. There are indications that the concentration and presence of certain of volatile compounds in exhaled breath of lung cancer patients is different from concentrations in healthy volunteers. This might lead to a future diagnostic test for lung cancer.
Exhaled breath samples from 65 patients with different stages of lung cancer and undergoing different treatment regimes were analysed. Mixed expiratory and indoor air samples were collected. Solid phase microextraction (SPME) with carboxen/polydimethylsiloxane (CAR/PDMS) sorbent was applied. Compounds were analysed by means of gas chromatography (GC) and mass spectrometry (MS).
The method we used allowed identification with the spectral library of 103 compounds showing at least 15% higher concentration in exhaled breath than in inhaled air. Among those 103 compounds, 84 were confirmed by determination of the retention time using standards based on the respective pure compound. Approximately, one third of the compounds detected were hydrocarbons. We found aromatic hydrocarbons, alcohols, aldehydes, ketones, esters, ethers, sulfur compounds, nitrogen-containing compounds and halogenated compounds. Acetonitrile and benzene were two of 10 compounds which correlated with smoking behaviour. A comparison of results from cancer patients with those of 31 healthy volunteers revealed differences in the concentration and presence of certain compounds. The sensitivity for detection of lung cancer patients based on eight different compounds not seen in exhaled breath of healthy volunteers was 51% and the specificity was 100%. These eight potential markers for detection of lung cancer are 1-propanol, 2-butanone, 3-butyn-2-ol, benzaldehyde, 2-methyl-pentane, 3-methyl-pentane, n-pentane and n-hexane.
SPME is a relatively insensitive method and compounds not observed in exhaled breath may be present at a concentration lower than LOD. The main achievement of the present work is the validated identification of compounds observed in exhaled breath of lung cancer patients. This identification is indispensible for future work on the biochemical sources of these compounds and their metabolic pathways.
Clinical Chemistry and Laboratory Medicine 02/2009; 47(5):550-60. · 3.01 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A patient who presented with dyspnea and suspected interstitial pulmonary fibrosis suffered a fatal pulmonary haemorrhage with no feasible cause for bleeding. Autopsy revealed abundant amyloid deposits in both lungs with a diffuse alveolar septal distribution pattern. Amyloid was also found in the cardiac interstitium and in many vessel walls. Considering the affected organs and the histological characteristics, the deposits were regarded as light chain-type. Amyloidosis, which is generally an uncommon disease, very rarely affects the lung predominantly. Haemorrhagic diathesis is a known complication in amyloidosis patients, although fatal haemorrhage is rare and has not yet been reported solely of pulmonary origin. This report describes an uncommon case of idiopathic systemic amyloidosis mainly manifesting in the lungs. The diagnosis was established after fatal pulmonary haemorrhage caused by vessel impairment due to additional vascular amyloid deposits.
Pathology & Oncology Research 07/2008; 15(1):133-6. · 1.56 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Small Cell Lung Cancer (SCLC) is associated with intensive nicotine consumption and characterized by a very aggressive growth rate. Furthermore, metastases often appear very early. At the annual meeting of the "American Society of Clinical Oncology" (ASCO) 2007, recent issues which will influence the daily clinical practice were presented. New chemotherapy combinations such as carboplatin/irinotecan or pemetrexed as well as targeted therapies e.g. bevacizumab in combination with chemotherapy could extend our therapeutic options. A genetic polymorphism, which influences the pharmacokinetic of irinotecan, turned out to be one reason for the different outcome of an irinotecan/cisplatin therapy in a Japanese and Northern American population. In the field of radiotherapy, a phase III study showed for the first time a significant benefit in overall survival by prophylactic cranial radiation in the setting of extensive disease.
Wiener Medizinische Wochenschrift 02/2007; 157(21-22):562-8.
[Show abstract][Hide abstract] ABSTRACT: With about 20% of all lung cancers small cell lung cancer (SCLC) represents a major subset of this entity. Although therapeutic improvements did not receive as much attention as in non small cell lung cancer (NSCLC), many small steps of clinical progress have been achieved within the last 20 years. An optimal treatment should be based on an interdisciplinary treatment plan. The standard treatment in localized stages represents combined radiation and chemotherapy. Cisplatin and etoposide are in this concern considered as a gold standard. 3D-planned conformal radiotherapy should start as early as possible and should be applied concomitantly to chemotherapy and in certain cases even in a hyperfractionated treatment protocol. In very early stages surgical resection could be an option in selected cases. In advanced stages a platinum-based doublet offers high response rates. As already established in limited disease prophylactic cranial irradiation is now also indicated in extensive disease in case of any tumor remission. In the second line treatment and in patients with reduced performance status topotecan is recommended. Similar as in NSCLC pemetrexed might become an alternative treatment option in the second line setting. In the field of new targeted therapies bevacizumab achieved the most promising results. The present review highlights historical milestones and up-to-date trends in radiotherapy, chemotherapy and surgery. Furthermore, the role of experimental strategies and the management of certain special clinical situations are discussed.
Wiener klinische Wochenschrift 02/2007; 119(23-24):697-710. · 0.81 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Das kleinzellige Bronchialkarzinom (Small Cell Lung Cancer, SCLC) stellt mit ungefähr 20% einen wesentlichen Teil der Bronchialkarzinome
dar. Beim SCLC konnten in den letzten zwanzig Jahren viele klinisch relevante Verbesserungen erzielt werden. Im Vergleich
zum nichtkleinzelligen Bronchialkarzinom (Non Small Cell Lung Cancer, NSCLC) gelingt der Fortschritt hier jedoch nur in kleinen
Schritten. Die Grundlage einer optimalen Behandlung beinhaltet heute eine interdisziplinäre Therapieplanung. Im lokalisierten
Stadium stellt die Radiochemotherapie die Standardbehandlung dar. Dabei gilt eine platinhältige Kombinationstherapie nach
wie vor als Goldstandard. Eine moderne dreidimensional geplante Strahlentherapie sollte so früh wie möglich konkordant zur
Chemotherapie und im Einzelfall sogar hyperfraktioniert erfolgen. Im Frühstadium ist im Einzelfall auch eine operative Sanierung
zu erwägen. Im fortgeschrittenen Stadium zeigt eine platinhältige Kombinationschemotherapie die besten Resultate. Bei Tumorremission
ist sowohl im Frühstadium als auch im fortgeschrittenen Stadium eine prophylaktische Schädelbestrahlung indiziert. In der
Zweitliniensituation und bei reduziertem Allgemeinzustand wird der Einsatz von Topotecan empfohlen. Pemetrexed könnte sich
ähnlich wie beim NSCLC ebenfalls in der Zweitlinientherapieals Alternative etablieren. Bei den gezielten Tumortherapien sind
die Daten zu Bevacizumab erfolgversprechend. In dieser Übersichtsarbeit werden die historischen Meilensteine und die aktuellen
Trends der Chemotherapie, Strahlentherapie und Chirurgie beleuchtet. Weiters wird die Bedeutung experimenteller Therapieansätze
und das Management spezieller klinischer Situationen diskutiert.
With about 20% of all lung cancers small cell lung cancer (SCLC) represents a major subset of this entity. Although therapeutic
improvements did not receive as much attention as in non small cell lung cancer (NSCLC), many small steps of clinical progress
have been achieved within the last 20 years. An optimal treatment should be based on an interdisciplinary treatment plan.
The standard treatment in localized stages represents combined radiation and chemotherapy. Cisplatin and etoposide are in
this concern considered as a gold standard. 3D-planned conformal radiotherapy should start as early as possible and should
be applied concomitantly to chemotherapy and in certain cases even in a hyperfractionated treatment protocol. In very early
stages surgical resection could be an option in selected cases. In advanced stages a platinum-based doublet offers high response
rates. As already established in limited disease prophylactic cranial irradiation is now also indicated in extensive disease
in case of any tumor remission. In the second line treatment and in patients with reduced performance status topotecan is
recommended. Similar as in NSCLC pemetrexed might become an alternative treatment option in the second line setting. In the
field of new targeted therapies bevacizumab achieved the most promising results. The present review highlights historical
milestones and up-to-date trends in radiotherapy, chemotherapy and surgery. Furthermore, the role of experimental strategies
and the management of certain special clinical situations are discussed.
Wiener klinische Wochenschrift 01/2007; 119(23):697-710. · 0.81 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: The fast development of analytical techniques in the field of gas analysis can be compared to that of computers during the
last two decades. Not only speed but also sensitivity of analysis has been greatly improved, sometimes by a factor of 100
or more. This technological development has fostered the analysis of exhaled breath. Since this can be done in real-time, very fast biological processes can be monitored. Also simulation and modelling of haemodynamics and lung mechanics become
possible. During the next decade we will see miniaturized equipment (of the size of a cigarette box) appear. Here we review
and illustrate the rich diversity of compounds observed in exhaled breath with a particular focus on lung cancer patients.
Each of the many volatile compounds has its own particular biochemical background, and cell types with different genetic background
have been shown to have a different pattern of released and consumed volatile compounds. Nevertheless we still lack an understanding,
if and how genetic alterations, which are seen as the underlying cause of the transformation process, control the VOC phenotype
observed in patients or cancer cell lines. The concentration pattern of volatile compounds in exhaled breath may be used in
the future for phenotyping individuals in large-scale screening approaches. Also changes in VOC patterns may provide disease-relevant
information (e.g. on the activity of metabolizing enzymes). Future applications will also include the follow-up of exogenous
compounds which are ingested or inhaled as drugs, food components or components in cigarette smoke and metabolic products
of these compounds.
KeywordsExhaled breath analysis-Lung cancer-Volatile organic compounds-Gas chromatography mass spectrometry-Proton transfer reaction mass spectrometry
memo - Magazine of European Medical Oncology 3(3):106-112.