Screening for lung cancer: current status and future directions: Thomas A. Neff lecture

Processing Escape Mechanisms Through Altered Proteasomal Cleavage of Epitopes Affect Immune Response in Pulmonary Neuroendocrine Tumors

Background:

Immunotherapy, especially immune checkpoint inhibition, is one of the most sophisticated approaches in cancer therapy. Immune checkpoint inhibition has already been successfully applied for treatment of non-small cell lung cancer and various other entities. Unfortunately, 60% of the cases show signs of therapy resistance. Additionally, a proportion of cases shows initial insensitivity to immune checkpoint inhibition. We consider a novel escape mechanism in association with deficient proteasomal epitope processing to be one prominent reason for initial insensitivity and therapy resistance. Therefore, we aim to identify mutations in association with these so-called processing escapes, in a highly diverse collective of pulmonary neuroendocrine lung tumors.

Materials and Methods:

Seventy representative tumor specimens of pulmonary neuroendocrine lung tumors were analyzed retrospectively via immunohistochemical detection of CD4, CD8, CD68, and CD20 as well as programmed cell death protein 1 and programmed cell death 1 ligand 1 for tumor immune infiltration and composition. Afterward, samples were screened for alterations in 48 genes, including 221 known mutational hotspots by massive parallel sequencing using the Illumina TruSeq Amplicon-Cancer Panel. For prediction of proteasomal cleavage probabilities, an R implementation of the machine learning tool NetChop 3.1 was utilized.

Results:

Immune cell infiltration of different compositions could be found in the majority of tumors. Deficient epitope processing was revealed to be a common event in those with steady distribution across all different subtypes. Despite immune infiltration, no significant antitumor response could be detected.

Conclusion:

Since it is widely acknowledged that tumors need to avoid the immune system to ensure their survival, processing escapes should already be present during primary tumor development. In line, processing escapes can be found in all tumors, regardless of subtype and mutational burden. Furthermore, there is solid evidence that processing escapes have a negative impact on the antitumor activity of tumor infiltrating immune cells.

Glucosidase II beta subunit (GluIIβ) plays a role in autophagy and apoptosis regulation in lung carcinoma cells in a p53-dependent manner

PURPOSE

Glucosidase II plays a major role in regulating the post-translational modification of N-linked glycoproteins. Previously, we found that the beta subunit of glucosidase II (GluIIβ) levels are significantly increased in lung carcinoma tissues, indicating a potential role in lung tumorigenesis. Here, we investigated the role of GluIIβ in the regulation of autophagy and apoptosis in lung carcinoma- and immortalized human bronchial epithelial-derived cells.

METHODS

A selective glucosidase II inhibitor, bromoconduritol, was used to inhibit GluII enzyme activity and a siRNA-based technology was used to suppress the expression of the GluIIβ encoding gene PRKCSH in lung carcinoma cells differing in p53 status. Cell viability was assessed using a MTT assay, cell cycle progression was assessed using flow cytometry, autophagy was assessed using Western blotting and apoptosis was assessed using an annexin V-FITC/PI double labeling method.

RESULTS

We found that GluIIβ inhibition resulted in the induction of autophagy in all cell lines tested, but apoptosis in only wild-type p53 cells. We also found that GluIIβ inhibition dose-dependently decreased activation of the EGFR/RTK and PI3K/AKT signaling pathways. Although the apoptosis inducing effect of GluIIβ inhibition appeared to be p53-dependent, we found that a combined treatment with lysosomal inhibitors to block autophagy enhanced the apoptotic effect of GluIIβ inhibition in both wild-type p53 and p53-null cells.

CONCLUSIONS

Our data indicate that GluIIβ inhibition results in autophagy and apoptosis in lung carcinoma-derived cells, supporting the hypothesis that this enzyme may play a role in blocking these two tumor suppressive processes. Since blocking autophagy by lysosomal inhibitors enhanced the apoptosis-inducing effect of bromoconduritol, independent of p53 status, their combined use may hold promise for the treatment of cancer, particularly lung cancer.

Massive parallel sequencing and digital gene expression analysis reveals potential mechanisms to overcome therapy resistance in pulmonary neuroendocrine tumors

Background: Lung cancer is the leading cause of cancer-related deaths worldwide. 25% show neuroendocrine differentiation (typical/atypical carcinoids, large-/small-cell neuroendocrine carcinomas). Carcinoids present with long survival rates, but metastatic carcinoids correlate with decreased survival and are commonly insensitive to standard chemotherapy or radiation. Therefore, novel therapeutic strategies are urgently needed.

Material and methods: 70 representative tumor specimens were used for next-generation sequencing analysis of 14 genes related to therapy response. Additionally, mRNA-expression profiles of 60 matching samples were determined for 13 selected drug targets by using the NanoString nCounter technology.

Results: A number of features known to sensitize tumors for different targeted therapies could be identified, which hopefully improve the clinical management of this subgroup of lung neoplasias. In particular, EGFR expression was observed in the investigated tumors in a noteworthy manner. Additionally, MDM2 was strongly expressed in the majority of all samples whereas the expression of its physiological inhibitor, CDKN2A, was nearly absent in all low-grade tumors. TP53 showed a high frequency of variants in high-grade tumors but mutations were rare in carcinoids.

Conclusion: Based on our results, therapeutic approaches with MDM2-inhibitors and monoclonal anti-EGFR antibodies may be promising in pulmonary carcinoid tumors.

The assessment of the role of baseline low-dose CT scan in patients at high risk of lung cancer

BACKGROUND

Despite the progress in contemporary medicine comprising diagnostic and therapeutic methods, lung cancer is still one of the biggest health concerns in many countries of the world. The main purpose of the study was to evaluate the detection rate of pulmonary nodules and lung cancer in the initial, helical low-dose CT of the chest as well as the analysis of the relationship between the size and the histopathological character of the detected nodules.

MATERIAL/METHODS

We retrospectively evaluated 1999 initial, consecutive results of the CT examinations performed within the framework of early lung cancer detection program initiated in Szczecin. The project enrolled persons of both sexes, aged 55-65 years, with at least 20 pack-years of cigarette smoking or current smokers. The analysis included assessment of the number of positive results and the evaluation of the detected nodules in relationship to their size. All of the nodules were classified into I of VI groups and subsequently compared with histopathological type of the neoplastic and nonneoplastic pulmonary lesions.

RESULTS

Pulmonary nodules were detected in 921 (46%) subjects. What is more, malignant lesions as well as lung cancer were significantly, more frequently discovered in the group of asymptomatic nodules of the largest dimension exceeding 15 mm.

CONCLUSIONS

The initial, low-dose helical CT of the lungs performed in high risk individuals enables detection of appreciable number of indeterminate pulmonary nodules. In most of the asymptomatic patients with histopathologically proven pulmonary nodules greater than 15 mm, the mentioned lesions are malignant, what warrants further, intensified diagnostics.

Updates and controversies in the rapidly evolving field of lung cancer screening, early detection, and chemoprevention

Lung cancer remains the leading cause of cancer-related death in the United States. Cigarette smoking is a well-recognized risk factor for lung cancer, and a sustained elevation of lung cancer risk persists even after smoking cessation. Despite identifiable risk factors, there has been minimal improvement in mortality for patients with lung cancer primarily stemming from diagnosis at a late stage when there are few effective therapeutic options. Early detection of lung cancer and effective screening of high-risk individuals may help improve lung cancer mortality. While low dose computerized tomography (LDCT) screening of high risk smokers has been shown to reduce lung cancer mortality, the high rates of false positives and potential for over-diagnosis have raised questions on how to best implement lung cancer screening. The rapidly evolving field of lung cancer screening and early-detection biomarkers may ultimately improve the ability to diagnose lung cancer in its early stages, identify smokers at highest-risk for this disease, and target chemoprevention strategies. This review aims to provide an overview of the opportunities and challenges related to lung cancer screening, the field of biomarker development for early lung cancer detection, and the future of lung cancer chemoprevention.

Activation of angiogenesis differs strongly between pulmonary carcinoids and neuroendocrine carinomas and is crucial for carcinoid tumourgenesis

BACKGROUND

Lung cancer still remains the leading cause of cancer for men after prostate cancer and breast cancer for women. Angiogenesis is considered a major microenvironment modifier.

MATERIAL AND METHODS

Demographic data and study design; The study is based on a collective of twenty representative specimens of each tumour entity (Typical Carcinoid, Atypical Carcinoid, Large-Cell Neuroendocrine Carcinoma , Small Cell Lung Cancer) for mRNA expression analysis. The following methods were performed: RNA Extraction and RNA Integrity Assessment, NanoString CodeSet Design and Expression Quantification, NanoString Data Processing and Statistical Analysis.

RESULTS

KDR rendered significant association to aggressiveness of the tumour and decreases with increasing malignancy (p=0.049). A decreased expression of HIF1A and KDR mRNA as associated with a higher risk of tumour invasion in vessels (HIF1A: p=0.034; KDR: p=0.029). FIGF and HIF1A expression levels are significantly associated with progression-free survival (FIGF: p= 0.021; HIF1A: p= 0.049). CRHR2 and FLT4 are stronger expressed in female than in male patients (CRHR2: p=0.024, FLT4: p=0.004). FIGF expression is still significant between LCNEC and SCLC (p=0.023). FLT4 and KDR show highly significant association to one of the analysed groups (FLT4: p=0.001; KDR: p=0.006). Additionally, HIF1A expression differs significantly between these focus cohorts (p=0.018).

CONCLUSION

We should consider for clinical practice application which factors affect most the tumour growth and distal metastasis, thereafter investigate easy to administer drugs with low side effects. Probably a cluster system of therapy should be established where a drug targets simultaneously different pathways of the same origin.

The tumor suppressor, p53, contributes to radiosensitivity of lung cancer cells by regulating autophagy and apoptosis

PURPOSE

Cell death is one of the most important endpoints of radiosensitivity. The tumor suppressor p53 participates not only in regulation of apoptosis, but also in autophagy mechanism. In this study, H1299-P53 (with wild-type p53) and H1299-175H (with mutant 175H) were used, and the effects of p53 on radiosensitivity were analyzed.

METHODS

Cell models with different p53 status were established by gene engineering, and cell viability was examined by colony formation assay, and cell counting kit-8 (CCK-8), 3-Methyladenine, and Z-VAD were used to block autophagy and apoptosis, respectively. Western blot was used to detect protein expression; monodansylcadaverine (MDC) staining was used to analyze autophagy rate; DAPI/Propidium Iodide (PI) staining and flow cytometry were used to assess apoptosis and necrosis.

RESULTS

In parental H1299, H1299-P53, and H1299-175H cells, radiosensitivity exhibited different by colony formation and CCK-8 assay (D0: 1.764 Gy, 1.407 Gy and 1.695 Gy; Dq: 2.977 Gy, 1.199 Gy and 2.312 Gy in turn). The radiosensitization of p53 was associated with the increase of MDM2 and P21 expression. The ionizing radiation (IR)-induced apoptosis was significant in H1299-P53 compared with in H1299 and H199-175H (p < 0.05) by flow cytometry, and the expression of cleaved-caspase3 was increased in H1299-P53 cells. While the IR-induced autophagy was significant in H1299 cells (p < 0.01) and decreased in H1299-P53 and H1299-175H cells (p < 0.01) by MDC staining, the expression of MAPLC3II and Beclin-1 increased in H1299, but not in H1299-p53 and H199-175H cells. The IR-induced cell survival was significantly increased by Z-VAD-FMK and decreased by 3MA in H1299-P53 cells; IR- induced autophagy was significantly increased by Z-VAD-FMK in H1299-P53 cells (p < 0.01), but not changed in H1299 cells.

CONCLUSION

p53 could regulate radiosensitivity by inhibiting autophagy and activating apoptosis; autophagy provides a prosurvival mechanism, and p53 potently abrogated the IR-induced autophagy, while mutant 175H shown no effect on radiosensitivity, suggesting that individual treatment strategies should be based on p53 status in patients.

Two microRNA panels to discriminate three subtypes of lung carcinoma in bronchial brushing specimens

RATIONALE

Effective treatment for lung cancer requires accuracy in subclassification of carcinoma subtypes.

OBJECTIVES

To identify microRNAs in bronchial brushing specimens for discriminating small cell lung cancer (SCLC) from non-small cell lung cancer (NSCLC) and for further differentiating squamous cell carcinoma (SQ) from adenocarcinoma (AC).

METHODS

Microarrays were used to screen 723 microRNAs in laser-captured, microdissected cancer cells from 82 snap-frozen surgical lung specimens. Quantitative reverse-transcriptase polymerase chain reaction was performed on 153 macrodissected formalin-fixed, paraffin-embedded (FFPE) surgical lung specimens to evaluate seven microRNA candidates discovered from microarrays. Two microRNA panels were constructed on the basis of a training cohort (n = 85) and validated using an independent cohort (n = 68). The microRNA panels were applied as differentiators of SCLC from NSCLC and of SQ from AC in 207 bronchial brushing specimens.

MEASUREMENTS AND MAIN RESULTS

Two microRNA panels yielded high diagnostic accuracy in discriminating SCLC from NSCLC (miR-29a and miR-375; area under the curve [AUC], 0.991 and 0.982 for training and validation data set, respectively) and in differentiating SQ from AC (miR-205 and miR-34a; AUC, 0.977 and 0.982 for training and validation data set, respectively) in FFPE surgical lung specimens. Moreover, the microRNA panels accurately differentiated SCLC from NSCLC (AUC, 0.947) and SQ from AC (AUC, 0.962) in bronchial brushing specimens.

CONCLUSIONS

We found two microRNA panels that accurately discriminated between the three subtypes of lung carcinoma in bronchial brushing specimens. The identified microRNA panels may have considerable clinical value in differential diagnosis and optimizing treatment strategies based on lung cancer subtypes.

Relationship between tumor size and disease stage in non-small cell lung cancer

Background

Whether tumor size and stage distribution are correlated remains controversial. The objective is to assess the relationship between tumor size and disease stage distribution in non-small cell lung cancer (NSCLC).

Methods

We conducted a retrospective analysis of 917 cases of NSCLC that were resected in the Cancer Hospital of Fudan University and Shanghai Sixth Hospital between January 2000 and February 2009. Tumor sizes were grouped into five categories: ≤20 mm, 21 to 30 mm, 31 to 50 mm, 51 to 70 mm and ≥71 mm.

Results

Age and tumor size affected stage distribution: patients 60 years or older had a higher percentage of N0M0 disease than patients younger than 60 years (61.67% vs. 44.85%, p < 0.01). The smaller the tumor, the more likely the disease was N0M0 status (p < 0.05). For tumors ≤20 mm in diameter, the proportion of cases with N0M0 status was 70.79%, compared to 58.88% for 21 to 30 mm, 48.03% for 31 to 50 mm, 47.55% for 51 to 70 mm, 33.33% for ≥71 mm. The mean (± SD) tumor size of cases with N0M0 status was 37.17 ± 21.34 mm, compared to 45.75 ± 23.19 mm for cases with other status.

Conclusions

There is a statistically significant relationship between tumor size and distribution of disease stage of primary NSCLC tumors: the smaller the tumor, the more likely the disease is N0M0 status.

Curcumin inhibits COPD-like airway inflammation and lung cancer progression in mice

Recent studies have demonstrated that K-ras mutations in lung epithelial cells elicit inflammation that promotes carcinogenesis in mice (intrinsic inflammation). The finding that patients with chronic obstructive pulmonary disease (COPD), an inflammatory disease of the lung, have an increased risk of lung cancer after controlling for smoking suggests a further link between lung cancer and extrinsic inflammation. Besides exposure to cigarette smoke, it is thought that airway inflammation in COPD is caused by bacterial colonization, particularly with non-typeable Hemophilus influenzae (NTHi). Previously, we have shown that NTHi-induced COPD-like airway inflammation promotes lung cancer in an airway conditional K-ras-induced mouse model. To further test the role of inflammation in cancer promotion, we administered the natural anti-inflammatory agent, curcumin, 1% in diet before and during weekly NTHi exposure. This significantly reduced the number of visible lung tumors in the absence of NTHi exposure by 85% and in the presence of NTHi exposures by 53%. Mechanistically, curcumin markedly suppressed NTHi-induced increased levels of the neutrophil chemoattractant keratinocyte-derived chemokine by 80% and neutrophils by 87% in bronchoalveolar lavage fluid. In vitro studies of murine K-ras-induced lung adenocarcinoma cell lines (LKR-10 and LKR-13) indicated direct anti-tumoral effects of curcumin by reducing cell viability, colony formation and inducing apoptosis. We conclude that curcumin suppresses the progression of K-ras-induced lung cancer in mice by inhibiting intrinsic and extrinsic inflammation and by direct anti-tumoral effects. These findings suggest that curcumin could be used to protract the premalignant phase and inhibit lung cancer progression in high-risk COPD patients.

Do evolving practices improve survival in operated lung cancer patients? A biobank may answer

INTRODUCTION

Biobanks may play a pivotal role in lung cancer patients' management, research, and health policy. The Nancy "Centre of Biologic Resources" analyzed the evolving profiles of operated lung cancer patients and their management over 20 years.

METHODS

A total of 1259 consecutive patients operated upon from 1988 till 2007 were included. Survival rates were statistically compared before and after 1997. The parameters associated with a significant improvement of survival were determined.

RESULTS

After 1997, lung cancer was diagnosed at an earlier stage. For Squamous Cell Lung Cancer (SQCLC), stages IA increased from 5.4 to 19.5% and for Adenocarcinoma (ADC), stage IA increased from 9.9 to 24.7%. More women with stage I ADC were operated upon after 1997 (p = 0.01). More patients with Large Cell Lung Cancer were diagnosed recently. Recent patients received more adjuvant or neo-adjuvant chemotherapy (p < 0.001) and less radiotherapy (stage I SQCLC: p = 0.019, stage I ADC: p < 0.001). A longer overall patients' survival was observed after 1997 (chi test for SQLC and ADC independently p < or = 0.002). Among SQCLC long survivors, those at stage I-II, below 50 years, were more numerous. A longer survival was associated with early stage in ADC patients. Stage was the single constant factor for overall outcome.

CONCLUSION

Overall and stage-adjusted survival of operated lung cancer patients has been improved in the last decade due mainly to earlier diagnosis. The generalized use of computed tomography scan, chemotherapy, and a collegial management improved patients' survival.

Detection of nodules showing ground-glass opacity in the lungs at low-dose multidetector computed tomography: phantom and clinical study

OBJECTIVE

To investigate the effect of the radiation dose (tube current second product) and the attenuation value of nodules with ground-glass opacity (GGO) on their detectability at multidetector computed tomography (MDCT).

METHODS

We scanned a chest CT phantom that included simulated GGO nodules with an MDCT scanner. The attenuation value of the simulated lung parenchyma was -900 Hounsfield units (HU); it was -800 and -650 HU for the simulated GGO nodules. We used a tube current second product of 180 mA as the standard and 21, 45, 60, and 90 mAs as the low-dose and performed receiver operating characteristic analysis to compare the performance of 5 radiologists in detecting GGO nodules at each milliampere. To assess the detectability of GGO nodules on human lung images, the observers were presented with 38 GGO nodules from 15 patients. The 5 radiologists independently reviewed chest CT images at 21 and 45 mAs.

RESULTS

In the phantom study, the Az value for GGO nodules with a CT number of -800 HU was significantly lower at 21 than 180 effective mA (0.86 vs. 0.96; P < 0.01). There was no statistically significant difference in the Az value of GGO nodules with a CT number of -650 HU, irrespective of milliamperes used (P = 0.165). In the clinical study, 39.5% and 25.8% of GGO were missed at 21 and 45 mAs, respectively.

CONCLUSIONS

At MDCT, GGO nodules with a CT number of -650 HU or less were difficult to detect at the lower milliampere settings (21 and 45 mAs).

Clinical impact of high-throughput gene expression studies in lung cancer

Lung cancer is the leading cause of cancer death in the United States and the world. The high mortality rate results, in part, from the lack of effective tools for early detection and the inability to identify subsets of patients who would benefit from adjuvant chemotherapy or targeted therapies. The development of high-throughput genome-wide technologies for measuring gene expression, such as microarrays, have the potential to impact the mortality rate of lung cancer patients by improving diagnosis, prognosis, and treatment. This review will highlight recent studies using high-throughput gene expression technologies that have led to clinically relevant insights into lung cancer. The hope is that diagnostic and prognostic biomarkers that have been developed as part of this work will soon be ready for wide-spread clinical application and will have a dramatic impact on the evaluation of patients with suspect lung cancer, leading to effective personalized treatment regimens.

Design and Development of a New Multi-Projection X-Ray System for Chest Imaging

Overlapping anatomical structures may confound the detection of abnormal pathology, including lung nodules, in conventional single-projection chest radiography. To minimize this fundamental limiting factor, a dedicated digital multi-projection system for chest imaging was recently developed at the Radiology Department of Duke University. We are reporting the design of the multi-projection imaging system and its initial performance in an ongoing clinical trial. The system is capable of acquiring multiple full-field projections of the same patient along both the horizontal and vertical axes at variable speeds and acquisition frame rates. These images acquired in rapid succession from slightly different angles about the posterior-anterior (PA) orientation can be correlated to minimize the influence of overlying anatomy. The developed system has been tested for repeatability and motion blur artifacts to investigate its robustness for clinical trials. Excellent geometrical consistency was found in the tube motion, with positional errors for clinical settings within 1%. The effect of tube-motion on the image quality measured in terms of impact on the Modulation Transfer Function (MTF) was found to be minimal. The system was deemed clinic-ready and a clinical trial was subsequently launched. The flexibility of image acquisition built into the system provides a unique opportunity to easily modify it for different clinical applications, including tomosynthesis, correlation imaging (CI), and stereoscopic imaging.

Could CT screening for lung cancer ever be cost effective in the United Kingdom?

Background

The absence of trial evidence makes it impossible to determine whether or not mass screening for lung cancer would be cost effective and, indeed, whether a clinical trial to investigate the problem would be justified. Attempts have been made to resolve this issue by modelling, although the complex models developed to date have required more real-world data than are currently available. Being founded on unsubstantiated assumptions, they have produced estimates with wide confidence intervals and of uncertain relevance to the United Kingdom.

Method

I develop a simple, deterministic, model of a screening regimen potentially applicable to the UK. The model includes only a limited number of parameters, for the majority of which, values have already been established in non-trial settings. The component costs of screening are derived from government guidance and from published audits, whilst the values for test parameters are derived from clinical studies. The expected health gains as a result of screening are calculated by combining published survival data for screened and unscreened cohorts with data from Life Tables. When a degree of uncertainty over a parameter value exists, I use a conservative estimate, i.e. one likely to make screening appear less, rather than more, cost effective.

Results

The incremental cost effectiveness ratio of a single screen amongst a high-risk male population is calculated to be around £14,000 per quality-adjusted life year gained. The average cost of this screening regimen per person screened is around £200. It is possible that, when obtained experimentally in any future trial, parameter values will be found to differ from those previously obtained in non-trial settings. On the basis both of differing assumptions about evaluation conventions and of reasoned speculations as to how test parameters and costs might behave under screening, the model generates cost effectiveness ratios as high as around £20,000 and as low as around £7,000.

Conclusion

It is evident that eventually being able to identify a cost effective regimen of CT screening for lung cancer in the UK is by no means an unreasonable expectation.

Mutations in the EGFR kinase domain mediate STAT3 activation via IL-6 production in human lung adenocarcinomas

Persistently activated or tyrosine-phosphorylated STAT3 (pSTAT3) is found in 50% of lung adenocarcinomas. pSTAT3 is found in primary adenocarcinomas and cell lines harboring somatic-activating mutations in the tyrosine kinase domain of EGFR. Treatment of cell lines with either an EGFR inhibitor or an src kinase inhibitor had no effect on pSTAT3 levels, whereas a pan-JAK inhibitor (P6) blocked activation of STAT3 and inhibited tumorigenesis. Cell lines expressing these persistently activated mutant EGFRs also produced high IL-6 levels, and blockade of the IL-6/gp130/JAK pathway led to a decrease in pSTAT3 levels. In addition, reduction of IL-6 levels by RNA interference led to a decrease in tumorigenesis. Introduction of persistently activated EGFR into immortalized breast epithelial cells led to tumorigenesis, IL-6 expression, and STAT3 activation, all of which could be inhibited with P6 or gp130 blockade. Furthermore, inhibition of EGFR activity in multiple cell lines partially blocked transcription of IL-6 and concurrently decreased production and release of IL-6. Finally, immunohistochemical analysis revealed a positive correlation between pSTAT3 and IL-6 positivity in primary lung adenocarcinomas. Therefore, mutant EGFR could activate the gp130/JAK/STAT3 pathway by means of IL-6 upregulation in primary human lung adenocarcinomas, making this pathway a potential target for cancer treatment.

Factors influencing hospital costs of lung cancer patients in Northern Ireland

Lung cancer is a major cause of morbidity and mortality. In this paper, the hospital costs incurred by 724 lung cancer patients diagnosed in 2001 were determined by review of case notes. These represented all patients diagnosed with lung cancer in Northern Ireland on whom data existed in that year. Total hospital costs in the 12 months from presentation for the 724 patients were 3.99 million pounds. Average patient costs were 5,956 pounds for patients diagnosed with non-small cell lung cancer and 5,876 pounds for those with small cell lung cancer. The main component of cost was inpatient stay, representing between 62 and 84% of costs depending on cell type. Multivariate analyses revealed significant differences in cost related to staging, co-morbidities, age, and deprivation. Total annual hospital costs were 13 times as high as the estimated enforcement cost of the smoke-free legislation in Northern Ireland.

Fluorescence in situ hybridization in diagnostic cytology

Fluorescence in situ hybridization (FISH) is a technique that uses fluorescently labeled DNA probes to detect chromosomal alterations in cells. FISH can detect various types of cytogenetic alterations including aneusomy (ie, abnormalities of chromosome copy number), duplication, amplification, deletion, and translocation. Because tumor cells generally contain chromosomal alterations, FISH is able to detect cells that have chromosomal abnormalities consistent with neoplasia in exfoliative and aspiration cytology specimens. This review will discuss the utility of FISH for the detection of bladder, lung, pancreatobiliary, and esophageal carcinoma in cytologic specimens.

Screening for Lung Cancer

BACKGROUND

Lung cancer typically exhibits symptoms only after the disease has spread, making cure unlikely. Because early-stage disease can be successfully treated, a screening technique that can detect lung cancer before it has spread might be useful in decreasing lung cancer mortality.

OBJECTIVES

In this article, we review the evidence for and against screening for lung cancer with low-dose CT and offer recommendations regarding its usefulness for asymptomatic patients with no history of cancer.

RESULTS

Studies of lung cancer screening with chest radiograph and sputum cytology have failed to demonstrate that screening lowers lung cancer mortality rates. Published studies of newer screening technologies such as low-dose CT and "biomarker" screening report primarily on lung cancer detection rates and do not present sufficient data to determine whether the newer technologies will benefit or harm. Although researchers are conducting randomized trials of low-dose CT, results will not be available for several years. In the meantime, cost-effectiveness analyses and studies of nodule growth are considering practical questions but producing inconsistent findings.

CONCLUSIONS

For high-risk populations, no screening modality has been shown to alter mortality outcomes. We recommend that individuals undergo screening only when it is administered as a component of a well-designed clinical trial with appropriate human subjects' protections.

Partnerships in oncology and radiology: the role of radiology in the detection, staging, and follow-up of lung cancer

In this review, I examine the multifaceted role of radiology in the diagnosis, staging, and management of lung cancer, highlighting new applications and modalities such as computer-aided detection of lung nodules and positron emission tomography/computed tomography for staging and monitoring response to therapy. Lung cancer screening is also discussed.

Screening for lung cancer

The lethality of lung cancer is related to the advanced stage at diagnosis. Initial studies have demonstrated that screening computed tomography (CT) is effective in diagnosing lung cancer at an earlier stage when compared with current clinical practice, however the best clinical approach for screening detected nodules has to be defined. The population to be identified as high risk should be over 50 years of age and should have smoked at least one pack/day for 20 years. CT protocols should use multidetector CT, low dose and a 2.5 reconstruction interval. Diagnostic work-up on detected nodules should be designed according to size and consider CT at 3 or 12 months to evaluate doubling time, CT enhancement, PET/CT and/or FNAB or VATS. The prevalence of lung cancer in the screened population is 1.1%–2.7%, and the incidence is 0.2%–1.1%. Eighty-one percent of cancers are diagnosed in stage I. The percentage of surgery performed for benign lesions ranges from 21% to 55%. In our series, the overall mortality rate was 3.2% in 5 years. The results of randomized clinical studies, when available, will assess the real efficacy of CT in reducing lung cancer related mortality.

A Comparison of Cytology and Fluorescence in Situ Hybridization for the Detection of Lung Cancer in Bronchoscopic Specimens

STUDY OBJECTIVES

To determine the relative sensitivity and specificity of cytology and fluorescence in situ hybridization (FISH) for the detection of lung cancer in bronchoscopically obtained specimens.

DESIGN

Cytology and FISH were performed on brushing and washing specimens obtained from patients undergoing bronchoscopy for suspected lung cancer. FISH utilized the LAVysion probe set (Abbott Molecular; Des Plaines, IL), which contains locus-specific probes to 5p15, 7p12 (EGFR), 8q24 (C-MYC), and a centromeric probe to chromosome 6.

SETTING

Single-center, academic, tertiary medical center.

PARTICIPANTS

One hundred thirty-seven patients referred for bronchoscopy for suspicion of lung cancer.

INTERVENTIONS

Cytology and FISH were performed on bronchoscopic brushings and washings.

MEASUREMENTS AND RESULTS

One hundred thirty-seven patients undergoing bronchoscopy had pathology, FISH, and cytology results. FISH and cytology were performed on 123 washing and 78 brushing specimens. Sensitivities of FISH and cytology were 71% and 51% (p = 0.007), respectively, for brushing specimens, and 49% and 44% (p = 0.541) for washing specimens. When FISH and cytology results were combined, sensitivities were 75% and 61%, respectively, for brushing and washing specimens, which was significantly better (p < 0.001) than cytology alone. Specificities of FISH and cytology for patients with negative findings at the time of initial bronchoscopy were 83% and 100% (p = 0.125), respectively, for brushing specimens, and 95% and 100% (p = 0.500) for washing specimens.

CONCLUSIONS

These findings show that FISH is significantly more sensitive than conventional cytology for detecting lung cancer in bronchial brushing specimens; when combined with cytology, FISH can improve the diagnostic sensitivity of detecting malignancy in bronchial brushing and washing specimens.

Significance of non-calcified pulmonary nodules in patients with extrapulmonary cancers

BACKGROUND

This study sought to determine the rate and patterns of malignancy in patients with extrapulmonary cancers and non-calcified pulmonary nodules, and to develop a statistical model to guide clinicians regarding choice of patients for diagnostic biopsy.

METHOD

The medical records of 151 patients evaluated at the Memorial Sloan-Kettering Cancer Center between January 1999 and December 2001 for non-calcified pulmonary nodules were reviewed. Nodules were considered malignant based on the results of a diagnostic biopsy, and were considered benign if their appearance remained stable 2 years after the initial study, if they resolved, or if a biopsy showed a non-malignant condition.

RESULTS

Sixty four of 151 patients (42%) were diagnosed with malignant nodules; 32 had newly diagnosed lung cancers, 28 had metastatic spread of their primary cancers, and four had lesions that were either new cancers or of undetermined aetiology. On univariate analysis the likelihood of malignancy increased with nodule size, tobacco exposure, and the finding of a solitary nodule. On multivariable analysis only nodule size and tobacco exposure were predictive of malignancy. The model had good predictive accuracy (area under the curve 0.751) but had insufficient discrimination for use as a clinical tool to determine which patients should undergo diagnostic biopsy.

CONCLUSION

Nearly half the non-calcified pulmonary nodules identified in this series were malignant. Lung cancer was more common than metastatic disease. These findings support the need for close interval follow up and a low threshold for diagnostic biopsy in patients with extrapulmonary cancers and non-calcified pulmonary nodules. In smokers, such lesions should raise concern for lung cancer.

A bibliometric analysis of global research production in respiratory medicine

STUDY OBJECTIVES

To evaluate the contribution of different world regions in respiratory research productivity.

METHODS

The world was divided into nine regions based on a combination of geographic, economic, and scientific criteria. Using the PubMed database, we retrieved information about the origin of articles from 30 journals included in the Respiratory System category of the Journal Citation Reports database for a 9-year period (1995 to 2003). We estimated the total number of publications, their mean impact factor, the product of these two parameters, and the research productivity per million of population of the world area divided by the gross national income per capita (GNIPC), for every year and the whole period of the study, for all defined world regions.

MEASUREMENTS AND RESULTS

Data on the country of origin of the publications was available for 48,614 of 49,382 retrieved articles (98.5%). The majority of articles published between 1995 and 2003 originated from Western Europe (40.4%) and the United States (35.4%). The research productivity compared to population and the GNIPC was found to be higher for Canada and Oceania compared to the United States and Western Europe. The rate of increase of the total published research product (number of published articles multiplied by the impact factor) was higher in the United States and Europe. The total research contribution of Asia, Eastern Europe, Central and Latin America, and Africa regarding the number of published articles was notably very low (approximately 8%).

CONCLUSIONS

The data suggest that there was a significant research activity in the field of respiratory medicine during the studied period. Although leaders of production of respiratory medicine research were from Western Europe and the United States, Canada, and Oceania had the best performance after adjustment for population and GNIPC.

Stereo CT image compositing methods for lung nodule detection and characterization

RATIONALE AND OBJECTIVES

Stereographic display has been proposed as a possible method of improving performance in reading computed tomographic (CT) examinations acquired for lung cancer screening. Optimizing such displays is important given the large volume of image data that must be evaluated for each of these examinations. This study is designed to explore certain tradeoffs between rendering methods designed for the stereo display of CT images.

MATERIALS AND METHODS

Stereo CT image compositing methods, including distance-weighted averaging, distance-weighted maximum intensity projection (MIP), and conventional MIP, were applied to lung CT images and compared for lung nodule detection and characterization.

RESULTS

Using the Jonckheere test indicated a statistically significant (P < .01) increase in contrast among the three compositing methods. Wilcoxon-Mann-Whitney test showed significant differences in contrast between distance-weighted averaging and conventional MIP (P < .01) and between averaging and distance-weighted MIP (P < .05), but not between distance-weighted MIP and conventional MIP (P > .05). Conventional MIP compositing provided the highest image contrast, but produced ambiguities in local geometric detail and texture, whereas averaging resulted in the lowest contrast, but preserved geometric detail. Distance-weighted MIP partially recovered geometric information, which was lost in images composited by means of conventional MIP.

CONCLUSION

Our results indicate that distance-weighted MIP may be a better choice for nodule detection in stereo lung CT images for its high local contrast and partial preservation of geometric information, whereas compositing by means of distance-weighted averaging is preferable for nodule characterization. The relative clinical value of these compositing methods needs to be evaluated further.

Future of early detection of lung cancer: the role of mouse models

Early detection represents one of the most promising approaches to improving lung cancer survival. To date, no screening strategies have been shown to decrease mortality from the disease. Furthermore, no reliable circulating biomarkers of lung cancer have been identified that allow early diagnosis. With the advent of gene targeting technology, new genetically engineered mouse models of lung cancer closely recapitulate the pathobiology of human disease. These mouse models have enabled novel approaches to early detection, including the identification of cancer-associated serum markers using proteomic technologies and the development of new molecular imaging tools. The application of innovative technologies to accurate mouse models promises to accelerate the discovery of new molecular targets and imaging biomarkers for the early detection of lung cancer.

Biomarkers for risk assessment in molecular epidemiology of cancer

One out of four deaths in the USA is due to cancer. Identification of populations at risk of developing cancer is important as it provides opportunities for prevention and treatment of cancer. Biomarkers are measurable indicators of exposure effects and susceptibility or disease state, and are used to understand the mechanisms of cancer progression. In recent molecular epidemiology studies genomic, proteomic, and epigenomic markers have been utilized which exhibit high sensitivity and specificity for different tumor types and can be assayed in biofluids and other specimens collected by non-invasive technologies. The current challenges and future directions in the field are discussed in this article.