Survival of patients with stage I lung cancer detected on CT screening

Screening programme evaluation applied to airport security

Eleni Linos, Elizabeth Linos, and Graham Colditz investigate whether airport security screening would pass the National Screening Committee’s criteria for an effective screening test

The LLP risk model: an individual risk prediction model for lung cancer

Using a model-based approach, we estimated the probability that an individual, with a specified combination of risk factors, would develop lung cancer within a 5-year period. Data from 579 lung cancer cases and 1157 age- and sex-matched population-based controls were available for this analysis. Significant risk factors were fitted into multivariate conditional logistic regression models. The final multivariate model was combined with age-standardised lung cancer incidence data to calculate absolute risk estimates. Combinations of lifestyle risk factors were modelled to create risk profiles. For example, a 77-year-old male non-smoker, with a family history of lung cancer (early onset) and occupational exposure to asbestos has an absolute risk of 3.17% (95% CI, 1.67-5.95). Choosing a 2.5% cutoff to trigger increased surveillance, gave a sensitivity of 0.62 and specificity of 0.70, while a 6.0% cutoff gave a sensitivity of 0.34 and specificity of 0.90. A 10-fold cross validation produced an AUC statistic of 0.70, indicating good discrimination.If independent validation studies confirm these results, the LLP risk models' application as the first stage in an early detection strategy is a logical evolution in patient care.

Panel of Serum Biomarkers for the Diagnosis of Lung Cancer

Purpose

Currently, a blood test for lung cancer does not exist. Serum biomarkers that could aid clinicians in making case management decisions would be enormously valuable. We used two proteomic platforms and a literature search to select candidate serum markers for the diagnosis of lung cancer.

Methods

We initially assayed six serum proteins, four discovered by proteomics and two previously known to be cancer associated, on a training set of sera from 100 patients (50 with a new diagnosis of lung cancer and 50 age- and sex-matched controls). Classification and Regression Tree (CART) analysis selected a panel of four markers that most efficiently predicted which patients had lung cancer. An independent, blinded validation set of sera from 97 patients (49 lung cancer patients and 48 matched controls) determined the accuracy of the four markers to predict which patients had lung cancer.

Results

Four serum proteins—carcinoembryonic antigen, retinol binding protein, α1-antitrypsin, and squamous cell carcinoma antigen—were collectively found to correctly classify the majority of lung cancer and control patients in the training set (sensitivity, 89.3%; specificity, 84.7%). These markers also accurately classified patients in the independent validation set (sensitivity, 77.8%; specificity, 75.4%). Remarkably, 90% of patients who fell into any one of three groupings in the CART analysis had lung cancer.

Conclusion

This panel of four serum proteins is valuable in suggesting the diagnosis of lung cancer. These data may be useful for treating patients with an indeterminate pulmonary lesion, and potentially in predicting individuals at high risk for lung cancer.

Long-term follow-up study of a population-based 1996–1998 mass screening programme for lung cancer using mobile low-dose spiral computed tomography

Early diagnosis and treatment are important for improvement of the low survival rate of patients with lung cancer. The objective of this study was to evaluate the long-term survival rate of patients identified to have lung cancer by our population-based baseline and annual repeat low-radiation dose computed tomography (low-dose CT) screenings, conducted in 1996-1998. A total of 13,037 CT scans were obtained from 5480 subjects (2969 men, 2511 women) aged 40-74 years at the initial CT screening. Lung cancer was detected in 63 subjects (57 were detected by CT scans and underwent surgery; 1 was detected by sputum cytology and underwent surgery; 3 rejected treatment; and 2 were interval cases that developed symptoms prior to the next annual repeat CT screening). Follow-up study included review of medical records. Death certificates were examined to check for any deceased interval case among participants. Postoperative follow-up of the 50 survived patients ranged from 70 to 117 (median, 101) months. Eight patients died during follow-up (6 due to lung cancer from 20 to 67 months after surgery and 2 deaths unrelated to lung cancer, each 7 and 60 months following surgery). Three patients who rejected treatment died 14 months to 6 years after positive screening CT scans, and the 2 interval cases died at each 17 and 30 months, respectively, following negative screening CT scans. Survival was analysed in 59 patients with lung cancer detected by low-dose CT screening (excluding two patients; one was detected by sputum cytology and the other had mass lesion already noted on the chest radiograph of the previous year). The 10-year survival calculated by the Kaplan-Meier method was 83.1% (95% CI: 0.735-0.927) for death from all causes and 86.2% (95% CI: 0.773-0.951) for death from lung cancer. The survival rate was excellent for never-smokers, patients with BAC and adenocarcinoma/mixed types with non-solid CT density pattern, associated with Noguchi's type A or B and pathologic stage IA. A poorer prognosis was noted in smokers with adenocarcinomas/mixed types, associated with part-solid or solid CT density pattern and Noguchi's type C or D. All patients with non-solid tumours measuring 6-13.5mm at presentation are alive, patients with part-solid tumours, measuring 17mm or more, or solid tumours, measuring 13mm or more at presentation were associated with increased risk of lung cancer-related morbidity or mortality. The estimated rate of possible over-diagnosis was 13% in total and we failed to cure 17% of patients encountered in the programme. Low-dose CT screening substantially improves the 10-year survival for lung cancer with minimal use of invasive treatment procedures.

The Lung Image Database Consortium (LIDC) data collection process for nodule detection and annotation

RATIONALE AND OBJECTIVES

The Lung Image Database Consortium (LIDC) is developing a publicly available database of thoracic computed tomography (CT) scans as a medical imaging research resource to promote the development of computer-aided detection or characterization of pulmonary nodules. To obtain the best estimate of the location and spatial extent of lung nodules, expert thoracic radiologists reviewed and annotated each scan. Because a consensus panel approach was neither feasible nor desirable, a unique two-phase, multicenter data collection process was developed to allow multiple radiologists at different centers to asynchronously review and annotate each CT scan. This data collection process was also intended to capture the variability among readers.

MATERIALS AND METHODS

Four radiologists reviewed each scan using the following process. In the first or "blinded" phase, each radiologist reviewed the CT scan independently. In the second or "unblinded" review phase, results from all four blinded reviews were compiled and presented to each radiologist for a second review, allowing the radiologists to review their own annotations together with the annotations of the other radiologists. The results of each radiologist's unblinded review were compiled to form the final unblinded review. An XML-based message system was developed to communicate the results of each reading.

RESULTS

This two-phase data collection process was designed, tested, and implemented across the LIDC. More than 500 CT scans have been read and annotated using this method by four expert readers; these scans either are currently publicly available at http://ncia.nci.nih.gov or will be in the near future.

CONCLUSIONS

A unique data collection process was developed, tested, and implemented that allowed multiple readers at distributed sites to asynchronously review CT scans multiple times. This process captured the opinions of each reader regarding the location and spatial extent of lung nodules.

Influence of detector collimation and beam pitch for identification and image quality of ground-glass attenuation and nodules on 16- and 64-detector row CT systems: Experimental study using chest phantom

OBJECTIVE

The purpose of the present study was to determine the influence of detector collimation and beam pitch for identification and image quality of ground-glass attenuation (GGA) and nodules on 16- and 64-detector row CTs, by using a commercially available chest phantom.

MATERIALS AND METHODS

A chest CT phantom including simulated GGAs and nodules was scanned with different detector collimations, beam pitches and tube currents. The probability and image quality of each simulated abnormality was visually assessed with a five-point scoring system. ROC-analysis and ANOVA were then performed to compare the identification and image quality of either protocol with standard values.

RESULTS

Detection rates of low-dose CTs were significantly reduced when tube currents were set at 40mA or less by using detector collimation 16 and 64x0.5mm and 16 and 32mmx1.0mm for low pitch, and at 100mA or less by using detector collimation 16 and 64x0.5mm and 16 and 32mmx1.0mm for high pitch (p<0.05). Image qualities of low-dose CTs deteriorated significantly when tube current was set at 100mA or less by using detector collimation 16 and 64x0.5mm and 16 and 32x1.0mm for low pitch, and at 150mA or less by using detector collimation 16 and 64x0.5mm and 16 and 32x1.0mm for high pitch (p<0.05).

CONCLUSION

Detector collimation and beam pitch were important factors for the image quality and identification of GGA and nodules by 16- and 64-detector row CT.

New molecularly targeted therapies for lung cancer

Lung cancer is the leading cause of cancer death worldwide. The disease is particularly difficult to detect, and patients often present at an advanced stage. Current treatments have limited effectiveness, and unfortunately, the prognosis remains poor. Recent insights into the molecular pathogenesis and biologic behavior of lung cancer have led to the development of rationally designed methods of early detection, prevention, and treatment of this disease. This article will review the important clinical implications of these advances, with a focus on new molecularly targeted therapies currently in development.

Performance profile of FDG-PET and PET/CT for cancer screening on the basis of a Japanese Nationwide Survey

OBJECTIVE

The aim of this study is to survey the situation of (18)F-fluorodeoxyglucose-positron emission tomography (FDG-PET) cancer screening in Japan and to describe its performance profile.

METHODS

"FDG-PET for cancer screening" was defined as FDG-PET or positron emission tomography and computed tomography (PET/CT) scan with or without other tests performed for cancer screening of healthy subjects. We sent questionnaires regarding FDG-PET cancer screening to 99 facilities in which FDG-PET tests were performed during the fiscal year 2005. Replies were obtained from 68 of the 99 facilities, of which 46 facilities performed FDG-PET cancer screening. The total number of subjects who underwent FDG-PET cancer screening was 50 558. From 38 of 46 facilities, reliable results of thorough examinations were obtained for the subjects who were positive by FDG-PET and/or one or more of the combined screening tests was performed and were referred for further evaluation. The total number of subjects in these 38 facilities amounted to 43 996.

RESULTS

A total of 50,558 healthy subjects underwent FDG-PET (including PET/CT) scanning with or without other tests for cancer screening in 46 PET centers during the fiscal year of 2005 in Japan. Thorough examination was indicated for 9.8% of the cases as a result of positive findings suggesting possible cancer. On analyzing 43 996 cases from 38 PET centers from which detailed information was obtained, 500 cases of cancers (1.14%) were found, of which 0.90% were PET positive and 0.24% were PET negative, resulting in the relative sensitivity of PET being 79.0%. Cancers of the thyroid, colon/rectum, lung, and breast were most frequently found (107, 102, 79, and 35 cases, respectively) with high PET sensitivity (88%, 90%, 80%, and 92%). PET showed an overall positive predictive value of 29.0%. PET/CT had a better detection rate, sensitivity, and positive predictive value than dedicated PET (P < 0.01).

CONCLUSIONS

We were able to clarify the performance profile of "FDG-PET for cancer screening" on the basis of a Japanese nationwide survey. The number of facilities possessing PET is increasing steadily, highlighting the necessity of evaluating the usefulness of "FDG-PET cancer screening" as soon as possible by undertaking long-term investigations of large series of subjects.

Performance of a computer-aided program for automated matching of metastatic pulmonary nodules detected on follow-up chest CT

OBJECTIVE

The purpose of this study was to evaluate the performance of a computer-aided program that allows automated matching of metastatic pulmonary nodules imaged with two serial clinical chest CT studies.

MATERIALS AND METHODS

The cases of 30 patients with metastatic pulmonary nodules depicted on two serial clinical MDCT scans (16- or 64-MDCT, 5-mm section thickness) were studied. The number of nodules per patient varied from a minimum of two to innumerable. A maximum of 10 well-defined solid nodules per patient, a total of 210 nodules, were selected from each baseline CT scan and were evaluated for matching detection in follow-up CT by means of an automated program. Substantial changes in lung findings and lung volumes between serial scans were visually assessed. The effects on matching rate of interval lung changes and location, size, and total number of nodules in the lung were analyzed with contingency tables. Chi-square tests were used to evaluate patterns for statistical significance.

RESULTS

The nodule-matching rate per patient ranged from 0 to 100% (median, 87.5%). By nodule, the overall matching rate was 140 of 210 (66.7%). Matching rate was highly associated with changes in lung quality between serial studies. Matching of 122 of 148 nodules (82.4%) occurred in 23 patients with relatively unchanged lung findings, compared with 18 of 62 nodules (29.0%) in seven patients with substantial interval changes (p < 0.001). The matching rate decreased with an increased total number of nodules per lung. For 10 or fewer nodules per lung, matching was successful for 31 of 36 nodules; for 11-50 nodules per lung, 60 of 73 nodules; for 51-100 nodules per lung, 33 of 47 nodules; and for more than 100 nodules per lung, 16 of 54 nodules (p < 0.001). The matching rate was not significantly different with location or size of nodules.

CONCLUSION

The rate of automated matching of metastatic pulmonary nodules on clinical serial CT scans was high (82.4%) when the lung findings and lung expansion between the serial scans were relatively unchanged. The rate decreased significantly, however, with substantial interval changes in the lung and a larger number of nodules.

CT-guided percutaneous fine-needle aspiration biopsy of pulmonary nodules measuring 10 mm or less

AIM

To determine the value of computed tomography (CT)-guided fine-needle aspiration biopsy (FNAB) of small pulmonary nodules measuring 10 mm or less.

MATERIAL AND METHODS

CT-guided FNABs of 55 nodules, measuring 10mm or less, were performed between January 2003 and February 2006. A coaxial technique was used, with an outer 19 G Bard Truguide needle and inner 22 G disposable Greene biopsy needle. Adequacy of specimens was assessed on-site by a cytotechnologist. The sizes of the nodules, distance from pleura, number of pleural punctures and aspirates, complications encountered, cytological diagnosis, and outcome were recorded.

RESULTS

The mean nodule diameter was 9 mm (range 5-10 mm). The average distance from the costal pleura was 31 mm (range 0-88 mm). In 50 of the 55 FNABs, the pleura was crossed once. An average of four aspirates was performed per case. Twenty-five FNABs (45.5%) were adequate for diagnosis (24 malignant and one tuberculosis). In 11 cases, where no definite diagnosis was made following FNAB, the outcome was not affected. In 10 cases, samples were insufficient for diagnosis and the nodules were subsequently diagnosed as malignant. Eight cases were excluded in the final analysis as follow-up details were unavailable. The sensitivity for malignancy and overall accuracy were 67.7 and 78.8%, respectively. Pneumothorax occurred in 29 (52.7%) patients, with five (9.1%) requiring thoracostomy tubes.

CONCLUSION

CT-guided FNAB is a useful tool in the diagnosis and management of small pulmonary nodules, despite the lower diagnostic accuracy and higher complication rate than those of larger pulmonary lesions.

Chromosomal aneusomy in bronchial high-grade lesions is associated with invasive lung cancer

RATIONALE

The development of lung cancer (LC) is accompanied by field changes in the airway mucosa that may have prognostic importance.

OBJECTIVES

To compare patients with prevalent LC to control subjects regarding their histologic dysplasia scores and chromosomal aneusomy as measured by fluorescence in situ hybridization (FISH).

METHODS

The most advanced bronchial histology lesion was assessed from each of 44 LC cases and 90 cancer-free control subjects using a four-color FISH probe set encompassing the chromosome 6 centromere, 5p15.2, 7p12 (epidermal growth factor receptor), and 8q24 v-myc myelocytomatosis viral oncogene homolog (MYC) sequences. Histology grades were coded as dysplasia (moderate or severe) or carcinoma in situ (CIS).

MEASUREMENTS AND MAIN RESULTS

CIS was the highest histologic grade for 32 subjects, and dysplasia was the highest grade for 102 subjects (54 moderate, 48 severe). Chromosomal aneusomy was seen in 64% of the LC cases, but in only 31% of the control subjects (odds ratio [OR], 4.68; 95% confidence interval [CI]. 1.97-11.04). Among those with any level of dysplasia, the OR for positive FISH and LC was 2.28 (95% CI, 0.75-6.86). Among those with CIS, the OR for positive FISH and LC was 5.84 (95% CI, 1.31-26.01).

CONCLUSIONS

Chromosomal aneusomy is associated with LC. Prospective examination of aneusomy as a precursor lesion that predicts LC is needed.

Identification of a panel of sensitive and specific DNA methylation markers for lung adenocarcinoma

Background

Lung cancer is the number one cancer killer of both men and women in the United States. Three quarters of lung cancer patients are diagnosed with regionally or distantly disseminated disease; their 5-year survival is only 15%. DNA hypermethylation at promoter CpG islands shows great promise as a cancer-specific marker that would complement visual lung cancer screening tools such as spiral CT, improving early detection. In lung cancer patients, such hypermethylation is detectable in a variety of samples ranging from tumor material to blood and sputum. To date the penetrance of DNA methylation at any single locus has been too low to provide great clinical sensitivity. We used the real-time PCR-based method MethyLight to examine DNA methylation quantitatively at twenty-eight loci in 51 primary human lung adenocarcinomas, 38 adjacent non-tumor lung samples, and 11 lung samples from non-lung cancer patients.

Results

We identified thirteen loci showing significant differential DNA methylation levels between tumor and non-tumor lung; eight of these show highly significant hypermethylation in adenocarcinoma: CDH13, CDKN2A EX2, CDX2, HOXA1, OPCML, RASSF1, SFPR1, and TWIST1 (p-value << 0.0001). Using the current tissue collection and 5-fold cross validation, the four most significant loci (CDKN2A EX2, CDX2, HOXA1 and OPCML) individually distinguish lung adenocarcinoma from non-cancer lung with a sensitivity of 67–86% and specificity of 74–82%. DNA methylation of these loci did not differ significantly based on gender, race, age or tumor stage, indicating their wide applicability as potential lung adenocarcinoma markers. We applied random forests to determine a good classifier based on a subset of our loci and determined that combined use of the same four top markers allows identification of lung cancer tissue from non-lung cancer tissue with 94% sensitivity and 90% specificity.

Conclusion

The identification of eight CpG island loci showing highly significant hypermethylation in lung adenocarcinoma provides strong candidates for evaluation in patient remote media such as plasma and sputum. The four most highly ranked loci, CDKN2A EX2, CDX2, HOXA1 and OPCML, which show significant DNA methylation even in stage IA tumor samples, merit further investigation as some of the most promising lung adenocarcinoma markers identified to date.

Lung cancer screening with spiral CT: baseline results of the randomized DANTE trial

BACKGROUND

Despite the high survival rates reported for screening-detected cases, the potential of screening of high-risk subjects for reducing lung cancer mortality is still unproven. We herewith present the baseline results of a randomized trial comparing screening for lung cancer with annual spiral computed tomography (CT) versus a yearly clinical review.

METHODS

Male subjects, 60-74 years old, and smokers of 20+ pack-years were enrolled. All participants received a baseline medical examination, chest X-rays (CXR) and sputum cytology upon accrual. Subjects randomized in the spiral CT group received a spiral CT scan at baseline, then yearly for the following 4 years. For controls, a yearly clinical examination was scheduled for the following 4 years.

RESULTS

2472 subjects were randomized (1276 spiral CT arm, 1196 controls). Age, smoking exposure and co-morbid conditions were similar in the two groups. In the spiral CT group, 28 lung cancers were detected, 13 of which were visible in the baseline chest X-rays (overall prevalence 2.2%). Sixteen out of 28 tumours (57%) were stage I, and 19 (68%) were resectable. In the control group, eight cases were detected by the baseline chest X-rays (prevalence rate 0.67%), four (50%) were stage I, and six (75%) were resectable.

CONCLUSIONS

Baseline lung cancer detection rate in the spiral CT arm was higher than in most published studies. The stage I detection rate was increased four-fold by spiral CT versus chest X-rays. However, more tumours in an advanced stage were also detected by CT. The high resection rate of screening-detected patients suggests a possible increase in cure rate. However, longer follow-up is required for definitive conclusions. This trial has been registered at www.Clinicaltrials.gov, registration No. NCT00420862.

New screening method for lung cancer by detecting volatile organic compounds in breath

Lung cancer is a frequent cause of cancer-related deaths in the world. There is no valid screening process and this limits its detection to the late stages, with consequently high mortality rates. Volatile organic compounds (VOC) are chemical compounds (mainly the products of cell catabolism) found as gases in the human breath. Different methods have been developed to analyse VOCs and to compare them in healthy subjects and lung cancer patients. In this review, we summarise the different techniques used to analyse VOC. Many reports have been published with promising results similar to those achieved with accepted screening methods such as mammography. These methods show good perspectives on lung cancer screening.

Baseline results of the Depiscan study: A French randomized pilot trial of lung cancer screening comparing low dose CT scan (LDCT) and chest X-ray (CXR)

BACKGROUND

Lung cancer has the highest mortality-rate per cancer, with an overall 5-year survival <15%. Several non-randomized studies pointed out the high sensitivity of low dose computed tomography (LDCT) to detect early stage lung cancer. In France, Depiscan, a pilot RCT of LDCT versus chest X-ray (CXR), started on October 2002 to determine the feasibility of enrollment by general practitioners (GPs), investigations and diagnostic procedures by university hospital radiologists and multidisciplinary teams, data management by centralized clinical research assistants, and anticipate the future management of a large national trial.

METHODS

GPs and occupational physicians (OPs) selected and enrolled 1000 subjects in 1 year. Eligible subjects were asymptomatic males or females aged 50-75 years with a current or former cigarette smoking history of >/=15 cigarettes per day for at least 20 years (former smokers having quit <15 years prior to enrollment). Based to randomization, annual LDCT or CXR screenings were planned at baseline and annually for 2 years.

RESULTS

Between October 2002 and December 2004, 765 subjects were enrolled by 89 out of the 232 participating GPs and OPs. Complete clinical and imaging baseline data were available for 621 individuals out of the 765 enrolled, due to 144 noncompliant subjects who withdrew their consent. At least one nodule was detected in 152 out of 336 subjects (45.2%) in the LDCT screening, versus 21 out of 285 subjects (7.4%) in the CXR screening arm. Eight lung cancers were detected in the LDCT arm and one in the CXR arm.

DISCUSSION

This pilot trial allows estimating that non-calcified nodules are 10 [6.36-17.07] times more often detected from LDCT than from CXR. However enrollment by GPs was more difficult than expected with 41% active investigators and a high rate (19%) of noncompliant patients. This experience speaks to the need for a high level of GPs formation and a large, coordinated clinical research team in such a trial.

TRIAL REGISTRATION NUMBER

02526.

International comparisons of survival from lung cancer: pitfalls and warnings

Population-based survival data can provide valuable comparative data on outcome but should be interpreted with caution. Differences in data collection and analysis, patient and tumor characteristics and treatment options can have an impact on reported results. Ideally, data from the whole population, including clinical-only diagnoses, should be reported and the methods of case identification described. The relative survival rates should preferably be given. Data on patient characteristics such as age, sex, ethnicity and socioeconomic deprivation should be described, together with tumor details such as pathology and clinical stage. Whenever possible, details on the use of treatments should be reported.

Potentially useful biomarkers for the diagnosis, treatment and prognosis of lung cancer

Lung cancer ranks top in both incidence and mortality in most part of the world. Scientists strive to explore biomarkers and their possible role in the diagnosis, treatment and prognosis of lung cancer. The ultimate goal is to discover biomarkers that can be tested in clinical trials and finally applied to patient care. Highly elevated concentrations of cytokeratin 19 fragment, tissue polypeptide antigen and squamous cell carcinoma antigen in non-small cell lung cancer particularly for squamous cell carcinoma, carcinoembryonic antigen and cancer antigen 125 in adenocarcinoma or non-small cell lung cancer, as well as progastrin-releasing peptide and neuron specific enolase in small cell lung cancer are suggestive biomarkers for the malignancy. Despite extensive studies, most results still remain controversial. Even with the report of high percent sensitivity and specificity, validation by clinical trials in large cohorts of patients is necessary before the cancer-related phenotypes can be translated into the clinic as reliable biomarkers. Nevertheless, identifications of biomarkers are leading to more understanding of the molecular pathways involved in lung cancer. It is hoped that understanding the connections between cellular pathways will help to reduce the suffering and loss of life caused by the lethal disease. This article summarizes the pre-clinical and translational researches against lung cancer in relation to biomarker discovery and validation. It is intended for policy makers, researchers, clinicians and other health professionals, offering a variety of useful biomarkers and updated data of clinical trials for lung cancer.

S-adenosylmethionine as a biomarker for the early detection of lung cancer

BACKGROUND

S-Adenosylmethionine (AdoMet) is a major methyl donor for transmethylation reactions and propylamine donor for the biosynthesis of polyamines in biological systems, and therefore may play a role in lung cancer development. We hypothesized that AdoMet levels were elevated in patients with lung cancer and may prove useful as a biomarker for early lung cancer.

METHODS

High-performance liquid chromatography was used to analyze plasma AdoMet levels in triplicate samples from 68 patients. This included 13 patients with lung cancer, 33 smokers with benign lung disease, and 22 healthy nonsmokers. The three groups of subjects were compared with respect to the distribution of demographic and disease characteristics and AdoMet levels. Distributions were examined using summary statistics and box plots, and nonparametric analysis of variance procedures.

RESULTS

Serum AdoMet levels were elevated in patients with lung cancer as compared to smokers with benign lung disorders and healthy nonsmokers. There were no significant correlations between AdoMet levels and tumor cell types, nodule size, or other demographic variables.

CONCLUSIONS

Our data demonstrate that plasma levels of AdoMet are significantly elevated in patients with lung cancer. Plasma AdoMet levels may prove to be a useful tool for the diagnosis of early lung cancer, in combination with chest CT. Registered at: clinicaltrials.gov (NCT00301119).

Postoperative Prognosis in Patients with Non-small Cell Lung Cancer According to the Method of Initial Detection

INTRODUCTION

In this study, we investigated the difference in the surgical results of non-small cell lung cancer according to the method of initial detection.

METHODS

We reviewed the medical records of 796 patients who underwent pulmonary resection for non-small cell lung cancer between 1994 and 2005. The subjects consisted of 171 patients whose cancer was detected by a medical checkup or mass health screening (group I), 316 patients who were under evaluation for other diseases or with symptoms related to other diseases (group II), and 309 patients with lung cancer-related symptoms (group III). The mean ages of the three groups were 63.2, 69.7, and 68.2 years old, respectively, with group I being significantly younger than the other groups. The proportion of women in the symptomatic group was significantly lower than that of men.

RESULTS

Pathologic stage I lung cancer was found in 112 (65.5%), 209 (65.2%), and 110 (35.6%) patients in groups I, II, and III, respectively. In comparison with stage II-IV cancer, stage I cancer was diagnosed more frequently in group I. According to the histologic type, adenocarcinoma was found in 132 patients (77.2%) in group I. However, squamous cell carcinoma was detected in only 27 patients (15.8%) in group I. The overall 5-year survival rates were 71.9%, 60.2%, and 48.0% in groups I, II, and III, respectively. Groups I and II had significantly better prognoses than group III.

CONCLUSION

Groups I and II had favorable prognoses, and the presence of symptoms related to lung cancer was a significantly unfavorable prognostic factor independent of all other factors.

Biomarkers for lung cancer: clinical uses

PURPOSE OF REVIEW

Biomarkers for lung cancer may be used for risk stratification, early detection, treatment selection, prognostication and monitoring for recurrence. All these areas of clinical management would benefit from sensitive and specific, noninvasive, cost-effective biomarkers.

RECENT FINDINGS

Significant progress has been made in understanding the steps involved in lung carcinogenesis and in the development of novel technologies for biomarker discovery. Over the last 3 years research into prospective lung cancer biomarkers has proliferated, especially in the areas of early detection and prognostication. The most active areas of research have been in promoter methylation, proteomics and genomics. Many investigators are adopting panels of serum biomarkers in an attempt to increase sensitivity. The development of targeted lung cancer therapy has engendered interest in markers to identify the optimal candidates for these therapies.

SUMMARY

Much progress has been made in the last 3 years in the identification and validation of new biomarkers for the early diagnosis of lung cancer. The biomarkers require additional studies before they can be used clinically. Markers to identify lung cancer patients who may benefit from targeted therapy have been developed more rapidly and may be used now in some clinical situations.

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.

Beliefs among Physicians in the Diagnostic and Therapeutic Approach to Non-small Cell Lung Cancer

PURPOSE

The American College of Chest Physicians (ACCP) has established evidence-based guidelines for the evaluation and treatment of patients with lung cancer. Physicians' beliefs and practice patterns may differ significantly from established guidelines. We conducted a survey to assess and compare physician beliefs against the evidence-based guidelines.

METHODS

A survey was sent by electronic mail (e-mail) in March 2006 to 2100 randomly selected physicians who were members of the ACCP practicing in the United States, followed by two reminder e-mails.

RESULTS

Three hundred forty-seven surveys were completed and evaluable. The majority (84%) of the respondents reported having read, consulted, or used the guidelines to set practice policies, and 75% found the guidelines helpful. The respondents' practice beliefs were in agreement with the guidelines on the evaluation of operable patients with enlarged mediastinal lymph nodes, the role of chemotherapy in the treatment of stage III disease, and the evaluation of a solitary pulmonary nodule. Nevertheless, a significant percentage of respondents' practice beliefs differed from the guidelines on issues such as screening for lung cancer, the survival benefit of chemotherapy in stage IV disease, and postoperative radiation therapy. Only a minority of respondents believed that chemotherapy improved quality of life in stage IV disease. The survey results indicate that there has been acceptance of the adjuvant chemotherapy and increasing integration of positron emission tomography in the evaluation of a solitary pulmonary nodule and in staging the mediastinum.

CONCLUSIONS

The majority of physicians found the evidence-based guidelines beneficial; nevertheless, practice beliefs differ from the guidelines in select areas.

Role of Positron Emission Tomography Scanning in the Management of Lung Nodules Detected at Baseline Computed Tomography Screening

BACKGROUND

Indeterminate noncalcified lung nodules are a frequent finding when low-dose computed tomography (LD-CT) is used for lung cancer screening. The best clinical management for such nodules remains uncertain. We present results using positron tomography scanning (CT-PET) to evaluate LD-CT-detected lung nodules during the first year of the Continuing Observation of Smoking Subjects (COSMOS) early detection trial for lung cancer.

METHODS

A total of 5200 asymptomatic current or former smokers (> or = 20 pack-years) older than 50 years of age were enrolled in a single-institution screening trial using annual LD-CT. Growing nodules and those with a maximum diameter exceeding 8 mm were studied with CT-PET. Transthoracic needle biopsy was not a routine part of the protocol.

RESULTS

During the first year of study, 157 subjects underwent CT-PET, 66 of whom underwent surgical biopsy. Of the 58 lung cancers found on surgical biopsy, 51 were positive (standard uptake value > 2.0) and seven were negative for malignancy by CT-PET. Sensitivity was 88% overall, but 100% in the subgroup with solid nodules of 10 mm or more. Among the 8 patients with benign disease at surgical biopsy, CT-PET was positive in 6 and negative in 2.

CONCLUSIONS

CT-PET is a highly promising modality for identifying potentially malignant lesions in screening-detected lung nodules and appears particularly useful as an alternative, in the screening setting, to invasive procedures for the further investigation of uncertain nodules. Our findings also indicate that the standard uptake value threshold for positivity should be lowered for small nodules (< 10 mm). Longer follow-up and larger prospective studies are necessary to confirm these preliminary findings.

Impaired flow-mediated dilation is associated with low pulmonary function and emphysema in ex-smokers: the Emphysema and Cancer Action Project (EMCAP) Study

RATIONALE

Basic science research suggests a causal role for endothelial dysfunction in chronic obstructive pulmonary disease (COPD). Clinical studies examining endothelial function are lacking, particularly early in the disease. Flow-mediated dilation (FMD) is a physiologic measure of endothelial reactivity to endogenous nitric oxide.

OBJECTIVES

We hypothesized that lower FMD among former smokers would be associated with lower post-bronchodilator FEV(1), higher percentage of emphysema using computed tomography (CT) and lower diffusing capacity.

METHODS

We measured FMD, pulmonary function, and CT percentage of emphysema in a random sample of 107 cotinine-confirmed former smokers in the ongoing EMCAP study. FMD was defined as percentage change in the brachial artery diameter with reactive hyperemia. Generalized additive models were used to adjust for potential confounders and assess linearity.

MEASUREMENTS AND MAIN RESULTS

Mean age of participants was 71 +/- 5 years, 46% were female, and pack-years averaged 48 +/- 26. Mean FMD was 3.8 +/- 3.1%; mean post-bronchodilator FEV(1), 2.3 +/- 0.8 L; and mean CT percentage of emphysema, 26 +/- 10%. A 1 SD decrease in FMD was associated with a 132-ml (95% confidence interval, 16-248 ml; P = 0.03) decrement in post-bronchodilator FEV(1) and a 2.6% (95% confidence interval, 0.5-4.7%; P = 0.02) increase in CT percentage of emphysema in fully adjusted models. These associations were linear across the spectrum from normality to disease, independent of smoking history, and also significant among participants without COPD. Associations with diffusing capacity were consistent but nonsignificant (P = 0.09). The FMD-FEV(1) association was entirely attributable to percentage of emphysema.

CONCLUSIONS

Impaired endothelial function, as measured by FMD, was associated with lower FEV(1) and higher CT percentage of emphysema in former smokers early in COPD.

Prediction of lung cancer using volatile biomarkers in breath

BACKGROUND

Normal metabolism generates several volatile organic compounds (VOCs) that are excreted in the breath (e.g. alkanes). In patients with lung cancer, induction of high-risk cytochrome p450 genotypes may accelerate catabolism of these VOCs, so that their altered abundance in breath may provide biomarkers of lung cancer.

METHODS

VOCs in 1.0 L alveolar breath were analyzed in 193 subjects with primary lung cancer and 211 controls with a negative chest CT. Subjects were randomly assigned to a training set or to a prediction set in a 2:1 split. A fuzzy logic model of breath biomarkers of lung cancer was constructed in the training set and then tested in subjects in the prediction set by generating their typicality scores for lung cancer.

RESULTS

Mean typicality scores employing a 16 VOC model were significantly higher in lung cancer patients than in the control group (p<0.0001 in all TNM stages). The model predicted primary lung cancer with 84.6% sensitivity, 80.0% specificity, and 0.88 area under curve (AUC) of the receiver operating characteristic (ROC) curve. Predictive accuracy was similar in TNM stages 1 through 4, and was not affected by current or former tobacco smoking. The predictive model achieved near-maximal performance with six breath VOCs, and was progressively degraded by random classifiers. Predictions with fuzzy logic were consistently superior to multilinear analysis. If applied to a population with 2% prevalence of lung cancer, a screening breath test would have a negative predictive value of 0.985 and a positive predictive value of 0.163 (true positive rate =0.277, false positive rate =0.029).

CONCLUSIONS

A two-minute breath test predicted lung cancer with accuracy comparable to screening CT of chest. The accuracy of the test was not affected by TNM stage of disease or tobacco smoking. Alterations in breath VOCs in lung cancer were consistent with a non-linear pathophysiologic process, such as an off-on switch controlling high-risk cytochrome p450 activity. Further research is needed to determine if detection of lung cancer with this test will reduce mortality.

Lung cancer screening

The result of a lung cancer screening program should be fewer lung cancer-specific deaths in the screened population. Studies evaluating chest imaging as a screening tool for lung cancer have not shown a reduction in lung cancer-specific mortality to date. The ability of institutions using chest imaging to meet the criteria for successful screening programs has also been debated. Contentious issues include the presence of an overdiagnosis bias, the ability to find preclinical disease at a curable point in time, the amount of pseudodisease identified, and the cost-effectiveness of screening programs. Current guidelines remain vague as randomized trials are being completed and technologic advances are occurring. The ultimate face of a successful lung cancer screening program is yet to be defined.

Natural History of Stage I Non-Small Cell Lung Cancer

BACKGROUND

Concern has been raised that early detection of lung cancer may lead to the treatment of clinically indolent cancers. No population-based study has examined the natural history of patients with stage I NSCLC who receive no surgery, chemotherapy, or radiation therapy. Our hypothesis is that long-term survival in patients with untreated stage I non-small cell lung cancer (NSCLC) is uncommon.

METHODS

A total of 101,844 incident cases of NSCLC in the California Cancer Center registry between 1989 and 2003 were analyzed; 19,702 patients had stage I disease, of whom 1,432 did not undergo surgical resection or receive treatment with chemotherapy or radiation. Five-year overall survival (OS) and lung cancer-specific survival were determined for this untreated group, for subsets of patients who were recommended but refused surgical resection, and for T1 tumors.

RESULTS

Only 42 patients with untreated stage I NSCLC were alive 5 years after diagnosis. Five-year OS for untreated stage I NSCLC was 6% overall, 9% for T1 tumors, and 11% for patients who refused surgical resection. Five-year lung cancer-specific survival rates were 16%, 23%, and 22%, respectively. Among these untreated patients, median survival was 9 months overall, 13 months for patients with T1 disease, and 14 months for patients who refused surgical resection.

CONCLUSION

Long-term survival with untreated stage I NSCLC is uncommon, and the vast majority of untreated patients die of lung cancer. Given that median survival is only 13 months in patients with T1 disease, surgical resection or other ablative therapies should not be delayed even in patients with small lung cancers.

Lung cancer screening: has there been any progress? Computed tomography and autofluorescence bronchoscopy

PURPOSE OF REVIEW

Advances in imaging technologies are currently being explored in the attempt to reduce lung cancer morbidity and mortality by achieving stage shift. We reviewed recent important publications on lung cancer screening.

RECENT FINDINGS

Autofluorescence bronchoscopy has established its important role in the intervention of early central airway lesions. Multidetector computed tomography (CT) and CT-positron emission tomography may facilitate diagnosis of early parenchymal lung lesions. Practical implications of screening are reaching far beyond early diagnostic efforts per se as lead-time, length-time, overdiagnosis biases combined with low specificity of screening tests undermine its cost-effectiveness in the era of healthcare budget constraints.

SUMMARY

Advanced imaging technologies may allow early detection and prudent intervention in some individuals that harbour asymptomatic early lung cancer, but disproportional expenses may be required to sieve out many more individuals at risk to attain stage shift. Confounding co-morbidities and practical hurdles may reduce screening's efficacy as it is plausible that for the majority of smokers, lung cancer may not be the ultimate cause of suffering since 90% of them will not develop lung cancer. This fact remains true despite increased use of noninvasive and minimally invasive technologies for the maximum preservation of quality of life irrespective of whether early intervention is a success or failure.

Small solid noncalcified pulmonary nodules detected by screening chest computed tomography

We aimed to determine the outcome of small (<10 mm) solid noncalcified pulmonary nodules detected by chest computed tomography (CT) scans. Reports of low-dose chest CT scans performed from October 2003 to April 2005 at the Seoul National University Hospital Healthcare System Gangnam Center were reviewed to identify patients with solid noncalcified pulmonary nodules smaller than 10 mm. Partly solid and nonsolid nodules or nodules without follow-up imaging within 1 year were excluded. Records were studied to determine if the initial nodules had changed in size. A total of 3478 chest CT examinations were performed, with 232 patients having small noncalcified nodules (6.7%). One hundred and thirty-eight patients met the criteria (104 men and 34 women) and 213 nodules were identified. The median age was 54 years (range 32-80) and at least 86 patients (62%) were at low to intermediate risk for developing lung cancer. The largest nodule was less than 5 mm in diameter in 87 patients (63%) and 5 mm or more in 51 patients (37%). None of the nodules grew and 29 (14%) decreased in size at follow-up CT scans performed within 12 months. When those individuals at low to intermediate risk for lung cancer were included, solid noncalcified subcentimeter nodules were less frequently found in low-dose CT screening and were nearly unchanged in size when a follow-up CT scan was done within 12 months.