Circulating markers of cellular immune activation in prediagnostic blood sample and lung cancer risk in the Lung Cancer Cohort Consortium (LC3)

Cell-mediated immune suppression may play an important role in lung carcinogenesis. We investigated the associations for circulating levels of tryptophan, kynurenine, kynurenine:tryptophan ratio (KTR), quinolinic acid (QA) and neopterin as markers of immune regulation and inflammation with lung cancer risk in 5,364 smoking-matched case-control pairs from 20 prospective cohorts included in the international Lung Cancer Cohort Consortium. All biomarkers were quantified by mass spectrometry-based methods in serum/plasma samples collected on average 6 years before lung cancer diagnosis. Odds ratios (ORs) and 95% confidence intervals (CIs) for lung cancer associated with individual biomarkers were calculated using conditional logistic regression with adjustment for circulating cotinine. Compared to the lowest quintile, the highest quintiles of kynurenine, KTR, QA and neopterin were associated with a 20-30% higher risk, and tryptophan with a 15% lower risk of lung cancer (all ptrend < 0.05). The strongest associations were seen for current smokers, where the adjusted ORs (95% CIs) of lung cancer for the highest quintile of KTR, QA and neopterin were 1.42 (1.15-1.75), 1.42 (1.14-1.76) and 1.45 (1.13-1.86), respectively. A stronger association was also seen for KTR and QA with risk of lung squamous cell carcinoma followed by adenocarcinoma, and for lung cancer diagnosed within the first 2 years after blood draw. This study demonstrated that components of the tryptophan-kynurenine pathway with immunomodulatory effects are associated with risk of lung cancer overall, especially for current smokers. Further research is needed to evaluate the role of these biomarkers in lung carcinogenesis and progression.

Reproductive and hormonal factors and the risk of lung cancer: the EAGLE study

Evidence about the role for reproductive and hormonal factors in the etiology of lung cancer in women is conflicting. To clarify this question, we examined 407 female cases and 499 female controls from the Environment And Genetics in Lung cancer Etiology population-based case-control study. Subjects were interviewed in person using a computer-assisted personal interview to assess demographics, education, smoking history, medical history, occupational history, reproductive and hormonal factors. Associations of interest were investigated using logistic regression models, adjusted for catchment area and age (matching variables), cigarette smoking (status, pack-years and time since quitting). Additional confounding variables were investigated but did not substantially affect the results. We observed a reduced risk of lung cancer among women with later age at first live birth [≥31 years: odds ratio (OR) = 0.57, 95% confidence interval (CI) = 0.31-1.06, p-trend = 0.05], later age at menopause (≥51 years: OR = 0.49, 95%CI = 0.31-0.79, p-trend = 0.003) and longer reproductive periods (≥41 years: OR = 0.44, 95%CI = 0.25-0.79, p-trend = 0.01). A reduced risk was also observed for hormone replacement therapy (OR = 0.63, 95%CI = 0.42-0.95, p = 0.03) and oral contraceptive use (OR = 0.67, 95%CI = 0.45-1.00, p = 0.05) but no trend with duration of use was detected. Menopausal status (both natural and induced) was associated with an augmented risk. No additional associations were identified for other reproductive variables. This study suggests that women who continue to produce estrogens have a lower lung cancer risk. Large studies with great number of never smoking women, biomarkers of estrogen and molecular classification of lung cancer are needed for a more comprehensive view of the association between reproductive factors and lung cancer risk.

Nedaplatin and irinotecan in patients with large-cell neuroendocrine carcinoma of the lung

BACKGROUND

No standard chemotherapy has been established for patients with large-cell neuroendocrine carcinoma (LCNEC).

PATIENTS AND METHODS

Patients with LCNEC of the lung were treated with nedaplatin (NP) at 50 mg/m(2) and irinotecan at 50 mg/m(2) on days 1 and 8 every four weeks for four cycles.

RESULTS

Data for 18 of the LCNEC patients were retrospectively analyzed. All patients were male, with a performance status 0 or 1, and the median age was 68 (range 58-80) years. Nine patients received adjuvant chemotherapy after undergoing complete surgical resection. Fourteen patients were able to receive four cycles of nedaplatin and irinotecan. Grade 4 leukopenia and neutropenia occurred in 5.6% and 16.7%, respectively. Four patients experienced grade 3 non-hematologic toxicities, such as diarrhea, enterocolitis, duodenal perforation and myocardial infarction. There were no treatment-related deaths. Two patients achieved complete response and four achieved partial response, and the median survival time was 12.3 months for the nine patients with advanced disease.

CONCLUSION

Nedaplatin plus irinotecan is effective and safe for patients with LCNEC of the lung.

Environmental tobacco smoke and lung cancer among Chinese nonsmoking males: might adenocarcinoma be the culprit?

No studies have specifically reported the association of lung adenocarcinoma with environmental tobacco smoke (ETS) exposure among nonsmoking males. The objective of this study was to examine the exposure-response relation between ETS exposure and lung cancer among nonsmoking males. In particular, the association with adenocarcinoma of the lung was studied. This is a population-based, case-referent study in Hong Kong during 2004-2006. A total of 132 Chinese male nonsmokers with newly diagnosed primary lung cancer and 536 nonsmoking community referents were interviewed about ETS exposures from the household and/or workplace, including ever ETS exposure, sources of exposure, number of smoking cohabitants/coworkers, and smoker-years. Univariate logistic regression analyses showed a weak association between all lung cancers and ever ETS exposure from the household and/or workplace (odds ratio (OR) = 1.11, 95% confidence interval (CI): 0.74, 1.67), but an increased risk was restricted to adenocarcinoma (OR = 1.68, 95% CI: 1.00, 2.38). After adjustment for family cancer history and other confounders, excess risk (OR = 1.62, 95% CI: 0.91, 2.88) still persisted for adenocarcinoma, although it was no longer statistically significant. Exposure-response relations for adenocarcinoma were found with increasing levels of all ETS indices when exposures from the household and workplaces were combined. The consistent exposure-response relations between ETS exposures and adenocarcinoma suggested a probable causal link, which would have to be confirmed by future larger studies.

Marijuana use and the risk of lung and upper aerodigestive tract cancers: results of a population-based case-control study

BACKGROUND

Despite several lines of evidence suggesting the biological plausibility of marijuana being carcinogenic, epidemiologic findings are inconsistent. We conducted a population-based case-control study of the association between marijuana use and the risk of lung and upper aerodigestive tract cancers in Los Angeles.

METHODS

Our study included 1,212 incident cancer cases and 1,040 cancer-free controls matched to cases on age, gender, and neighborhood. Subjects were interviewed with a standardized questionnaire. The cumulative use of marijuana was expressed in joint-years, where 1 joint-year is equivalent to smoking one joint per day for 1 year.

RESULTS

Although using marijuana for > or =30 joint-years was positively associated in the crude analyses with each cancer type (except pharyngeal cancer), no positive associations were observed when adjusting for several confounders including cigarette smoking. The adjusted odds ratio estimate (and 95% confidence limits) for > or =60 versus 0 joint-years was 1.1 (0.56, 2.1) for oral cancer, 0.84 (0.28, 2.5) for laryngeal cancer, and 0.62 (0.32, 1.2) for lung cancer; the adjusted odds ratio estimate for > or =30 versus 0 joint-years was 0.57 (0.20, 1.6) for pharyngeal cancer, and 0.53 (0.22, 1.3) for esophageal cancer. No association was consistently monotonic across exposure categories, and restriction to subjects who never smoked cigarettes yielded similar findings.

CONCLUSIONS

Our results may have been affected by selection bias or error in measuring lifetime exposure and confounder histories; but they suggest that the association of these cancers with marijuana, even long-term or heavy use, is not strong and may be below practically detectable limits.

XRCC1 polymorphism and lung cancer risk in relation to tobacco smoking

DNA repair plays a critical role in protecting the genome of the cell from carcinogens or ionising radiation. Reduced DNA-repair capacity can increase susceptibility to occupational-induced cancer. Three coding polymorphisms at codons 194, 280, and 399 in X-ray cross complementing group 1 (XRCC1) DNA-repair gene have been identified, and it is possible that these polymorphisms may affect DNA- repair capacity and thus modulate cancer susceptibility. In the current German study, we investigated the role of XRCC1-polymorphisms as a genetic modifier of risk for individuals with lung cancer as susceptible genotypes, especially in relation to tobacco smoking. Three polymorphisms; XRCC1 Arg194Trp, XRCC1 Arg280His and XRCC1 Arg399Gln, were determined by real-time PCR analysis in 446 lung cancer patients and 622 controls. The observed allele frequencies in the population were within the range described for Caucasians. Multivariate analyses of lung cancer patients who carried at least one mutant variant allele of XRCC1 Arg194Trp (OR=1.03; 95%-CI: 0.66-1.61), XRCC1 Arg280His (OR=0.95; 95%-CI: 0.57-1.60), or XRCC1 Arg399Gln (OR=0.99 CI: 0.73-1.34), did not show any elevated risks. When analysed by histology, no individual subtype of lung cancer was significantly associated with the polymorphisms. Lung cancer risk rose significantly with higher cumulative cigarette consumption. Stratified analysis between tobacco smoking and variant genotypes revealed increasing risks for heavy smokers (>60 pack-years), with the presence of at least one copy of the XRCC1 Arg194Trp variant allele (OR=79.29; 95%-CI: 8.53-737.04) and the XRCC1 Arg399Gln (OR=61.87; 95%-CI: 15.65-244.67). By analysing the interaction between tobacco smoking and the genotypes, combined smoking and having the susceptible genotypes did not show a joint effect. In this study, the XRCC1 Arg194Trp, XRCC1 Arg280His, and XRCC1 Arg399Gln-polymorphisms, had no relevant modifying effect on lung cancer risk and cumulative smoking dose.

Lung cancer histopathology in the Thrace region of Turkey and comparison with national data

Following the trends in lung cancer (LC) morbidity and mortality rates can show past trends of cigarette smoking and can give clues on some geographical factors. The demographics of LC patients and the histopathologic distribution of their disease in the Thrace region of Turkey have yet to be defined. A retrospective chart review of primary LC patients admitted to the pulmonology department of Trakya University Hospital between 1992 and 2001 was performed. Charts were available for review in 521 of 567 patients. The mean age was 61 +/- 10 years (30-86 years) and 497 (95.4%) patients were male (male/female ratio= 20.7). When compared with national and international data, male/female ratio for the LC patients from Thrace region was higher than the ratio found from Turkey in general and also from other countries. Adenocarcinoma (ADC) was present in seven of the 24 (29.2%) of the females and prevalence of ADC was more than 2.5 times in females than males (p< 0.05). Squamous cell types were more common in males. Histopathological type did not vary with age in females, but small cell carcinoma was more prevalent in males under the age of 45 (44.7% if . 45 years old vs. 29.1% if > 45 years old, p< 0.05). These data may support that the LC associated with smoking is in the earlier phase of the epidemic in Thrace region. Monitoring the LC trend in our region can give clues on evolving cigarette design and smoking attitudes and geographic factors.

GSTM1, GSTT1, and GSTP1 polymorphism and lung cancer risk in relation to tobacco smoking

The impact of genetic polymorphisms in GSTM1, GSTP1 or GSTT1 on susceptibility to lung cancer has received particular interest since these enzymes play a central role in detoxification of major classes of tobacco carcinogens. In the current German study we investigated the role of GSTM1, GSTT1 and GSTP1 polymorphisms as a genetic modifier of risk for individuals with lung cancer as susceptible genotypes especially in relation to tobacco smoking. The GSTM1, the GSTP1 as well as GSTT1-polymorphism were determined by real time PCR analysis in 446 lung cancer patients and 622 controls. The observed allele frequencies of the GSTP1 polymorphism in the population were within the range described for Caucasians. Multivariate analyses of lung cancer patients, who carried at least one mutant variant allele of GSTP1 (OR=1.03; 95%-CI: 0.76-1.39) did not show any elevated risks. GSTM1 or GSTT1 null-genotypes were found in 47.3% resp. 18.5% of the controls and in 52.5% resp. 16.8% of the cancer patients. The estimated risk of the GSTM1 null genotype for lung cancer was OR=1.34 (95%-CI: 0.99-1.81) and for the GSTT1 null genotype OR=0.88 (95%-CI: 0.59-1.32). When analyzed by histology no individual subtype of lung cancer was strongly associated with the polymorphisms. Lung cancer risk rose significantly with higher cumulative cigarette consumption confirming the association with smoking-related lung cancer risk. Stratified analysis between tobacco smoking and variant genotypes revealed for heavy smokers (>60 pack-years) increasing risks at the presence for at least one copy of the GSTP1 variant allele OR=50.56 (95%-CI: 15.52-164.79). The corresponding risks for GSTM1 null genotypes were OR=112.08 (95%-CI: 23.02-545.71) and for the GSTT1 null-genotype OR=158.49 (95%-CI: 17.75-1415.06) in smokers >60 pack-years. Analysing the interaction between tobacco smoking and the genotypes, combined smoking and having the susceptible genotypes did not show a joint effect. In this study polymorphisms of the GSTM1, GSTT1 or GSTP1 had no relevant modifying effect on lung cancer risk and cumulative smoking dose.

Cigarette smoking and risk of large cell carcinoma of the lung: a case-control study in Uruguay

In the time period 1988-2000, a case-control study on large cell carcinoma of the lung was conducted in Montevideo, Uruguay. The study included 149 cases (139 men and 10 women) and 596 controls (556 men and 40 women) afflicted with diseases not related with tobacco smoking. Cases and controls were frequency matched on age, sex, residence and urban/rural status. According to our results, large cell carcinoma was strongly related with cigarette smoking (OR for heavy smokers 155.2, 95% CI: 30.6-786.1). Furthermore, all cases displayed higher risks for intensity compared with smoking duration. Smokers of black tobacco showed odds ratios (ORs) significantly higher than those presented by smokers of blond tobacco and smoking cessation displayed a reduction in risk of 95%, close to the risk of never smokers. Finally, filter use was not associated with any reduction in risk. It could be concluded that undifferentiated large cell carcinoma of the lung could be included among those lung tumors classified as Kreyberg I cancers.

[Epidemiological features of bronchial carcinoma cases with environmental asbestos exposure]

Due to environmental asbestos exposure, asbestos related lung diseases are common in Eskisehir district of Anatolia. In this study we aimed both to determine the epidemiological findings of the patients diagnosed as bronchial carcinoma and to discuss the features, which were probably related to asbestos exposure, presented by the patients. From May 1997 to December 2000, 301 cases were included in the study. Of the patients, 97 (32.2%) had epidermoid cell type, 84 (27.9%) had small cell, 39 (13%) had adenocarcinoma, 4 (1.3%) had large cell. Adenocarcinomas were more frequent in women. There were not significant differences among the cell types from the point of view of the age distributions. Adenocarcinomas were more frequently located in lower lobes of the lungs (36.9%) and more frequently showed peripheral locations (45.9%) than other cell types (20.6% for epidermoid and 14.6% for small cell). Pleural effusion was more detected in adenocarcinomas (48.7% to 17.3% in epidermoid, 18.3% in small cell). The duration of smoking was shortest in adenocarcinomas, mean 32.4 years; the same duration was 56.2 years for epidermoid carcinomas. Of the patients, 54% had asbestos exposure. Adenocarcinomas were more frequently detected in the patients who exposed to asbestos but did not smoke. Our findings support that asbestos exposure may increase adenocancer frequency. The epidemiological and clinical features of adenocancer cases exposed to asbestos environmentally were not different than those of adenocancer cases exposed to asbestos occupationally.

Aberrant p16 promoter methylation in smokers and former smokers with nonsmall cell lung cancer

Hypermethylation of cytosines in CpG-rich islands of the promoter regions of regulatory genes has been discovered as a common mechanism of gene silencing during carcinogenesis. We analysed 64 primary lung carcinomas for promoter methylation of the tumour suppressor genes (TSGs) p16 (p16(INK4a)/CDKN2A) and p14 (p14(ARF)) by methylation-specific PCR, in order to evaluate aberrant methylation as a potential biomarker for epigenetic alterations in tobacco-related lung cancer. Methylation of p16 was observed in 34% (22/64) of the lung tumours examined. In particular, p16 methylation occurred in nonsmall cell lung cancer (NSCLC) only, with 41 % (22/54) of the tumours being positive. The highest frequency was found in large cell carcinoma (5/7, 71%), followed by adenocarcinoma (9/25, 36%) and squamous cell carcinoma (7/21, 33%). Methylation of the p14 gene was less frequent in lung cancer (4/52, 8%). When association with tobacco smoking was analysed, 42% (21/50) of NSCLC from ever smokers exhibited p16 methylation. Interestingly, the analysis revealed a significantly higher risk of p16 methylation in former smokers as compared to current smokers [odds ratio (OR) 5.1; 95% confidence interval (CI) 1.3-22]. The difference was retained after adjustment for age (OR 3.7; 95% CI 0.9-17). The promoter methylation results were then combined with data on genetic alterations determined previously in the same set of tumours. This data similarly showed that p16 methylation in parallel with p53 gene mutation or p14 methylation occurred more frequently in former smokers than in current smokers (44% vs. 14%; P = 0.035). Taken together, our data suggest that analysis of promoter methylation in TSGs may provide a valuable biomarker for identification of groups with an elevated risk of cancer, such as smokers and ex-smokers.

Synchronous triple lung cancers after treatment for non-Hodgkin's lymphoma: metachronous quadruple cancers

After chemotherapy and radiotherapy for non-Hodgkin's lymphoma during a one-year period, a 66-year-old man developed synchronous triple lung cancers in both lungs. Of the three resected tumors, one was advanced large cell carcinoma with neuroendocrine morphology, and the other two were early squamous cell carcinoma without lymph node metastasis. Although he received repeated chemotherapy for lung cancer, the patient died of hepatic failure due to multiple liver metastases. Autopsy revealed disseminated metastasis of the large cell carcinoma with neuroendocrine morphology throughout the entire body, but no recurrence of malignant lymphoma or squamous cell carcinoma was found. To our knowledge, this is the first report of triple lung cancers occurring after treatment for malignant lymphoma.

Pleomorphic carcinoma: report of a case with massive pleural effusion and asbestos particles

Pleomorphic (spindle/giant cell) carcinoma (PC) is one subset of large cell carcinoma. It is well known that PC patients have a poor survival rate. This report describes a 68-year-old man with PC. The patient's tumor had a massive pleural effusion. A left lower lobectomy and partial resection of the left diaphragm, peritoneum, and parietal pleura were performed to remove the tumor. Numerous asbestos particles were found in the left lower lobe. This is the first reported case of PC which may have been caused by asbestos particles. Further investigation is needed into whether asbestos exposure causes PC.

Chemoprevention of lung cancer by non-steroidal anti-inflammatory drugs among cigarette smokers

We conducted an epidemiologic case control study of NSAIDs among 489 lung cancer patients and 978 control subjects. The case patients were diagnosed and treated during 1996-1999 at the James Cancer Hospital and Research Institute, Columbus, OH. Each lung cancer diagnosis was verified by examination of the pathology report. Population controls free of disease were obtained from health screening clinics and frequency-matched to the cases at a 2:1 rate. Matching characteristics included age, gender, and pack-years of cigarette smoking. In order to assess the effects of NSAIDs on tobacco carcinogenesis, only heavy smokers were included in the control group. Information on the use of aspirin, ibuprofen, and prescription NSAIDs was obtained by personal interviews. Effects of NSAIDs on lung cancer risk were assessed by estimating odds ratios (relative risks) with 95% confidence intervals and performing trend tests. Daily intake of NSAIDs for at least 2 years prior to interview was associated with a 68% reduction in the relative risk of lung cancer (RR, 0.32; 95% CI, 0.23-0.44; p<0.01). The inverse trend of lung cancer risk with increasing NSAID use was highly significant (p<0.01). Results were similar for men (RR, 0.41) and women (RR, 0.22), and for the individual compounds, aspirin (RR, 0.25) and ibuprofen (RR, 0.39). These results combined with the current molecular evidence suggest that regular NSAID intake may prevent tobacco carcinogenesis through COX-2 blockade.

Cigarette smoking and subsequent risk of lung cancer by histologic type in middle-aged Japanese men and women: the JPHC study

In order to update the findings of relative risk associated with cigarette smoking for lung cancer by histologic type in Japan, the data from a population-based cohort study of 91,738 men and women were analyzed. During 1990-1999, 422 lung cancer incident cases were identified. The relative risk for all incident cases associated with current smokers versus non-smokers was 4.5 [95% confidence interval (CI): 3.0-6.8] and 4.2 (95% CI: 2.4-7.2), for men and women, respectively. When divided by histologic type, relative risk for squamous cell carcinoma and small cell carcinoma was 12.7 (95% CI: 4.7-34.7) and 17.5 (95% CI: 4.9-62.1), while for adenocarcinoma it was 2.8 (95% CI: 1.6-4.9) and 2.0 (95% CI: 0.8-5.0) for men and women, respectively. We confirmed that the lung cancer risk in men rose with increasing cigarette smoking, especially the duration of smoking among current smokers and decreased after the cessation of smoking among former smokers. Unlike the US or European countries, the relative risk did not increase in this updated study, compared with previous studies in 1960s to 1990s in Japan either for all incident cases or for specific histologic types and the magnitude of relative risks was substantially lower than that observed in the US or European countries, especially for adenocarcinoma.

Association of L-myc polymorphism with lung cancer susceptibility and prognosis in relation to age-selected controls and stratified cases

The association of L-myc polymorphism with cancer susceptibility and prognosis has produced conflicting results. This may have been due to racial/ethnic differences and methodological variations in the studies, such as, control selection and case stratification. Therefore, we investigated the genotype distribution of the L-myc polymorphism in 169 lung cancer patients and 169 non-cancer controls, and analyzed the association of this polymorphism with cancer susceptibility and prognosis in relation to age-specific controls as well as stratified cases. The genotype frequencies in the Taiwanese non-cancer controls were 0.56 (L) and 0.44 (S). Chi-square (chi(2)) analysis indicated a significant difference in the Taiwanese genotype distribution of L-myc compared with that of African-Americans (P=0.001). Logistic regression analysis of cases/controls, adjusted for both age and sex, indicated that an increased frequency of the LL genotype was observed in early-staged patients compared with the non-cancer controls (OR=0.43, 95% CI, 0.20-0.94, P=0.03). In addition, the frequency of the LL genotype was significantly higher in stages I+II patients (47.4%) than in stages III+IV patients (28.4%) (P=0.05). Furthermore, the S allele frequency was significantly increased in stages III+IV patients (P=0.005). As both L-myc and p53 polymorphisms were analyzed for their prognostic value, the patients with an S allele of the L-myc gene and a Pro/Pro variant genotype of the p53 gene had significantly poorer prognoses compared with other patients (P=0.004, by the log rank test). These data suggest that the S allele of the L-myc polymorphism may be associated with lung cancer progression.

L-myc genotype is associated with different susceptibility to lung cancer in smokers

We have shown that L-myc genotype is associated with the risk of esophageal cancer from smoking and heavy drinking. In this study, we have analyzed the relationship between the L-myc genotypes and lung cancer risk from smoking in 191 Japanese lung-cancer patients and 241 non-cancer controls. The odds ratios (ORs) were markedly higher in SS and LS genotypes than in LL genotype; age-sex-adjusted ORs were 3.19, 2.30 and 0.92, respectively. This result suggests that the L-myc polymorphism may affect the induction of lung cancer by smoking. The OR for smoking in SS-genotype patients diagnosed within 2 years was higher than that in other SS patients, suggesting that smoking-related lung cancer in SS genotype might exhibit a poorer prognosis.

Effect of smoking cessation on major histologic types of lung cancer

STUDY OBJECTIVES

It is well-recognized that the risk of lung cancer declines after smoking cessation. However, the degree of decline in different histologic types of lung cancer is not well understood. We conducted a meta-analysis of peer-reviewed studies to assess the effect of smoking cessation on rates of major histologic types of lung cancer.

DESIGN

Studies published in English between 1970 and 1999 were identified through searches of computerized databases (ie, MEDLINE and CANCERLIT). Combined estimates of relative risk and 95% confidence intervals were calculated for 27 studies using fixed and random effects models. Separate analyses were conducted for men and women.

RESULTS

Smoking cessation was associated with a reduction in the risk of all the major histologic types of lung cancer. The highest reduction was in small cell lung carcinoma (SCLC) and squamous cell carcinoma (SQC), and the lowest reduction was seen in large cell cancer and adenocarcinoma. In women, the combined risks for SQC and SCLC were higher than those in men. The dose-response curve for intensity of smoking was steeper in women.

CONCLUSION

The findings of this study suggest that smoking cessation results in the greatest reductions for SCLC and SQC. This effect is most marked in heavy smokers, particularly among women.

A patient with asbestos-induced lung cancer complicated by silicosis

A 76-year-old male died of lung cancer. At first, he was diagnosed as a silicosis, because he had worked for 30 years as a caster in shipyard and large opacities detected by chest x-ray and CT scanning. After the operation of lung cancer, numerous asbestos bodies were observed in the operated lung tissues. The detailed occupational inquiry revealed his asbestos use as a caster in shipyard. Early stage of asbestosis was suspected by chest CT scanning, but not definitely diagnosed in premortal examinations. Asbestosis, pleural plaques, silicosis and large cell carcinoma of the lung were histopathologically confirmed at the autopsy. A patient with asbestos-induced lung cancer complicated by silicosis was rarely published in the literature.

Lung cancer in patients younger than 40 years in a multiracial Asian country

OBJECTIVE

This study aimed to determine whether the clinicopathological features of lung cancer in patients younger than 40 years differ from that of older patients in an Asian country.

METHODOLOGY

We undertook a review of the clinicopathological data of all patients with confirmed primary lung cancer at the Department of Medicine, University of Malaya Medical Centre, Kuala Lumpur, Malaysia, from October 1991 to September 1999.

RESULTS

Of the 580 patients with lung cancer, 36 (6.2%; 23 males, 13 females) were 21-39 years old at diagnosis. The percentage of people who had never smoked was higher among the younger patients (58.3% vs 19.1%, P < 0.001). Although adenocarcinoma was the most common cell type in both groups, its incidence was higher in the younger patients (24/36 (66.7%) vs 228/544 (41.9%), P = 0.007). The mean World Health Organization performance status at presentation was worse in the younger patients (2.4 vs 2, P = 0.007). In the case of non-small cell lung cancer, all the younger patients presented with either stage IIIb or metastatic disease compared to 77.2% of the older patients (P < 0.001).

CONCLUSIONS

Younger lung cancer patients were more likely than older patients to have never smoked, to have adenocarcinoma, and to present with poorer performance status and with more advanced-stage non-small cell lung cancer.

Frequent cyclin D1 expression in chromate-induced lung cancers

Ex-chromate workers are frequently afflicted with lung cancers, especially central-type squamous cell carcinomas (SCCs) of the lung. However, little is known about the molecular and cellular biologic characteristics of chromate-induced lung cancers. We investigated expression of cyclin D1, bcl-2, and p53 proteins in chromate-induced lung cancers by immunohistochemistry, compared with those in lung cancers from nonexposed individuals and those in individuals with pneumoconiosis. Of 19 chromate-induced lung cancers, 16 tumors were SCCs, including 11 central and 5 peripheral types. Eleven (69%) of 16 chromate SCCs showed cyclin D1 expression. In contrast, cyclin D1 expression was observed in only 3 (12%) of 26 SCCs from nonexposed individuals and 6 (16%) of 37 SCCs that developed in patients with pneumoconiosis, respectively. The frequency of cyclin D1 expression proved to be significantly higher in chromate-induced SCCs than in SCCs from nonexposed individuals and from those with pneumoconiosis (P < .001). When comparisons were extended to all histologic types of lung cancer, cyclin D1 expression was observed significantly more often in chromate-induced lung cancers than in lung cancers from nonexposed subjects and those from patients with pneumoconiosis (11 [58%] of 19 v 5 [10%] of 52, P < .001, and 7 [11%] of 63, P < .001, respectively). Frequencies of bcl-2 and p53 expression were not significantly different among lung cancers from ex-chromate workers, nonexposed individuals and those with pneumoconiosis. The current study suggests that cyclin D1 expression may be involved in the development of chromate-induced lung cancers, although its underlying mechanism remains to be determined.

k-ras mutation and occupational asbestos exposure in lung adenocarcinoma: asbestos-related cancer without asbestosis

Environmental carcinogen exposure is requisite for the development of nearly all lung cancer, and it is well known that asbestos exposure interacts synergistically with tobacco smoke to induce lung cancer. However, the precise molecular lesions induced by asbestos are unknown. Furthermore, it is also unknown whether asbestos carcinogenesis proceeds in a fashion independent of or dependent upon the induction of fibrosis in workers with high asbestos exposures. Previous studies have suggested that asbestos is associated with the presence of a k-ras mutation in adenocarcinoma of the lung. We aimed to test whether occupational asbestos exposure was associated with k-ras codon 12 mutations in lung adenocarcinoma tumors and to determine whether this was conditional on the presence of asbestosis. All newly diagnosed, resectable lung cancer patients receiving treatment at the Massachusetts General Hospital between November 1992 and December 1996 were eligible to participate. Because k-ras mutation is very strongly associated with adenocarcinoma, and men were more likely to be occupationally exposed to asbestos, the study was restricted to males with this histological diagnosis. There were 84 male patients with available questionnaire-derived work history data and paraffin-embedded tumor tissue for determination of k-ras mutation status. Chest radiographic evaluation was done for all of the patients who reported occupational exposure to asbestos. The prevalence of k-ras mutation was higher among those with a history of occupational asbestos exposure (crude odds ratio, 4.8; 95% confidence interval, 1.5-15.4) compared to those without asbestos exposure, and this association remained after adjustment for age and pack-years smoked (adjusted odds ratio, 6.9; 95% confidence interval, 1.7-28.6). An index score that weights both the dates of exposure and the estimated intensity of exposure indicated that those with k-ras mutations had significantly greater asbestos exposures than those without mutations (P < 0.01). Analysis of the descriptive components of exposure indicated that the duration of exposure was not associated with k-ras mutation, but that the time since initial exposure was significantly associated with mutation status. The association of k-ras mutation and reported asbestos exposure was not dependent on the presence of radiographic evidence of asbestos-related disease. These data suggest that asbestos exposure increases the likelihood of mutation at k-ras codon 12 and that this process occurs independently of the induction of interstitial fibrosis.

p53 protein, EGF receptor, and anti-p53 antibodies in serum from patients with occupationally derived lung cancer

The oncogene product epidermal growth factor receptor (EGF-R), the tumour suppressor gene product p53 and anti-p53 antibodies are detectable in the serum of certain cancer patients. Increased levels of some of these products were reported in lung cancer patients after occupational asbestos exposure and after exposure to polycyclic aromatic hydrocarbons or vinylchloride. In the first step, this study investigated the possible diagnostic value of serum EGF-R, p53-protein and anti-p53 antibodies, measured by an enzyme-linked immunosorbent assay, in lung tumour patients. In addition to being investigated on a molecular epidemiological basis, these parameters were examined as biomarkers of carcinogenesis, especially with regard to asbestos incorporation effects or of radon-induced lung cancers. Also, a possible effect of cigarette smoking and age dependence were studied. A total of 116 male patients with lung or pleural tumours were examined. The histological classification was four small-cell cancers, six large-cell cancers, 32 adenocarcinomas, 47 squamous carcinomas, 12 mixed lung carcinomas, five diffuse malignant mesotheliomas and ten lung metastasis of extrapulmonary tumours. Twenty-two lung cancers and all mesotheliomas were related to asbestos, 22 lung cancers were related to ionizing radiation and 61 patients had cigarette smoke-related lung cancer. Besides these patients 50 male patients with non-malignant lung or pleural diseases were included; of the latter eight subjects suffered from asbestosis. Controls were 129 male subjects without any lung disease. No significantly elevated or decreased serum values for p53 protein, EGF-R, or anti-p53 antibodies as a function of histological tumour type, age, or degree and type of exposure (asbestos, smoking, ionizing radiation) could be found. The utility of p53-protein, EGF-R and anti-p53 antibodies as routine biomarkers for screening occupationally derived lung cancers is limited.

Effect of green tea on p53 mutation distribution in ultraviolet B radiation-induced mouse skin tumors

In the present study, administration of green tea to SKH-1 mice, via the drinking fluid, was found to significantly reduce the incidence and volume of ultraviolet B (UVB) radiation-induced skin tumors. Thirty-six skin tumors induced by UVB and 32 skin tumors induced by UVB, in mice treated with green tea in their drinking water, were collected and examined for the presence of mutations in the p53 gene. Polymerase chain reaction products from p53 exons 5-8 were screened by single-strand conformation polymorphism and direct sequence analyses. Eight of 36 UVB-induced tumors contained nine p53 mutations, with four in exon 5 and five in exon 8. In contrast, nine of 32 UVB-induced tumors in mice treated with green tea contained 11 p53 mutations, with two in exon 5, five in exon 6 and four in exon 8. All of the p53 mutations occurred at dipyrimidine sequences. These results were further corroborated by p53 immunohistochemistry. The most frequent mutations were C-->T or T-->C transitions, which are consistent with the genetic alterations caused by UVB exposure. Interestingly, mutations found in exon 6 of the p53 gene occurred only in tumors from the UVB/green tea group. Thus, the tumors observed in UVB/green-tea-treated mice have a different exon distribution of p53 mutations than tumors obtained from mice treated with UVB alone.

Assay for erythrocyte superoxide dismutase activity in patients with lung cancer and effects on pollution and smoke trace elements

The antioxidative effect of CuZnSOD, which catalyzes the dismutation of superoxide anion (O2-), provides a defense against the oxygen toxicity. The object of the study is to evaluate the erythrocytes superoxide dismutase (SOD) activity in two groups of persons (Group I, healthy blood donors; Group II, lung cancer patients), using the spectrophotometric assay of NADH oxidation and the indirect method. The effect of trace elements, such as Al3-, Cr3+, Fe3+, Hg2+, NI2+, and Pb2+ (producing free radicals oxygen and present in pollution and smoke) is also evaluated. The results show the decrease of SOD activity in lung cancer patients with respect to healthy individuals. Likewise, in those patients the enzymatic activity is bigger in early stage (I,II) with respect to advanced one (III) (p < 0.05). The lesser activity when the samples are incubated with Ni or Pb point out that these metals play a role in neoplasm development. In short, the oxidant-antioxidant balance is altered in lung cancer patients.

Cigarette smoking and histologic type of lung cancer in men

STUDY OBJECTIVES

To determine whether intensity, duration, age at initiation, and cessation of cigarette smoking act differently in the development of various histologic types of lung cancer.

DESIGN

A case-control study among deceased men who underwent autopsy, a procedure that involves approximately 73% of all local deaths.

SETTING

The Province of Trieste in northeastern Italy

PARTICIPANTS

Seven hundred fifty-five patients with lung cancer, including 267 with squamous cell carcinoma, 218 with small cell carcinoma, 90 with large cell carcinoma, 158 with adenocarcinoma, and 22 with other histologic types, and 755 control subjects who had died of causes other than chronic lung diseases and certain tumors. Information on smoking habits, residential history, and occupational exposure was obtained from each subject's next of kin.

RESULTS

Compared with nonsmokers, the odds ratio (OR) for current smokers was 13.4 for all types combined, 18.8 for squamous cell carcinoma, 14.3 for small cell carcinoma, 34.3 for large cell carcinoma, and 7.9 for adenocarcinoma. Intensity of smoking, duration, age at starting, and dose were all directly associated with all histologic types of lung cancer, although the OR was lower for adenocarcinoma than for other cell types. When results were restricted to ever smokers, exposure-response curves were similar across histologic types. The risk of lung cancer attributable to smoking was 88% for all types combined, 91% for squamous cell carcinoma, 89% for small cell carcinoma, 95% for large cell carcinoma, and 82% for adenocarcinoma.

CONCLUSIONS

This study confirms that cigarette smoking causes all types of lung cancer, but the proportion of cases attributable to smoking is lower for adenocarcinoma than for other types, due to a higher proportion of nonsmokers.

Cigarette smoking and large cell carcinoma of the lung

Large cell carcinoma is the fourth most common histological type of lung cancer in the United States. Cigarette smoking causes large cell lung cancer, but it is uncertain whether the effect varies with the amount and duration of smoking. This uncertainty stems from ambiguity in the histopathological classification of large cell cancer, especially before 1971, and the relatively infrequent occurrence of large cell cancer in epidemiological studies. The present case-control investigation demonstrates that the risk of large cell cancer increases with both the frequency and number of years of cigarette smoking. The odds ratio associated with smoking two or more packs/day was 37.0 (95% confidence interval, 16.4-83.2) in men and 72.9 (35.4-150.2) in women. It is concluded that cigarette smoking is the predominant cause of large cell lung cancer.

Lung cancer in relation to exposure to silica dust, silicosis and uranium production in South African gold miners

BACKGROUND

A nested case-control study for lung cancer was performed on a cohort of 2260 South African gold miners in whom an association between exposure to silica dust and risk of lung cancer was previously reported. The objective was to investigate an expanded set of risk factors and also cancer cell type.

METHODS

The 78 cases of lung cancer found during the follow up period from 1970 to 1986 were matched with 386 controls. Risk of lung cancer was related to smoking, exposure to silica dust, incidence of silicosis, and uranium production and the uranium content of the mine ore.

RESULTS

The risk of lung cancer was associated with tobacco smoking, cumulative dust exposure, duration of underground mining, and with silicosis. The best predictive model included pack years of cigarette consumption (adjusted relative risk (RR) = 1.0 for < 6.5 pack years, 3.5 (95% confidence interval (CI) 0.7 to 16.8) for 6.5-20 pack years, 5.7 (95% CI 1.3 to 25.8) for 21-30 pack years, and 13.2 (95% CI 3.1 to 56.2) for more than 30 pack years) and silicosis (RR = 2.45 (95% CI 1.2 to 5.2)). No association was found with uranium production. The lung tumour cell type distribution was 40.3% small cell carcinoma, 38.8% squamous cell, 16.4% adenocarcinoma, and 4.5% large cell carcinoma. Small and large cell cancer combined were associated with exposure to dust.

CONCLUSIONS

The results cannot be interpreted definitively in terms of causal association. Possible interpretations are: (1) subjects with high dust exposure who develop silicosis are at increased risk of lung cancer; (2) high levels of exposure to silica dust on its own is important in the pathogenesis of lung cancer and silicosis is coincidental; and (3) high levels of silica dust exposure may be a surrogate for the exposure to radon daughters.

Metabolic phenotypes of retinoic acid and the risk of lung cancer

The metabolic activity of cytochrome P-450 enzymes has been associated with an increased risk of developing lung cancer. We found previously that all-trans retinoic acid is catabolized by these oxidative enzymes, and that an inhibitor of this system discriminated between two populations of lung cancer patients. We examined the association between this metabolic phenotype and the risk of lung cancer in 85 subjects. The area under the plasma concentration x time curve (AUC) was calculated after a single oral dose of all-trans retinoic acid (45 mg/m2). The mean AUC for patients who had either squamous or large cell carcinomas was significantly lower than that of patients with adenocarcinomas (P = 0.0001) or control subjects (P = 0.01). Individuals with an AUC < 250 ng x h/ml had a greater likelihood of having squamous or large cell carcinoma (odds ratio = 5.93). This study suggests that the "rapid" catabolism of all-trans retinoic acid is linked to an increased risk of squamous or large cell cancers of the lung.

Detection of human papillomavirus DNA in primary lung carcinoma by nested polymerase chain reaction

Human papillomaviruses (HPV) have been implicated in the pathogenesis of human squamous cell carcinoma, especially of cervical carcinomas. In two previous studies concerning squamous cell carcinomas of the lung, DNA of HPV subtypes 6/11/16/18 (and 31/33/35 for one study) was detected by in situ hybridization in 7% to 30% of the cases. A series of 31 frozen biopsies of lung carcinomas were examined for the presence of HPVDNA by nested polymerase chain reaction (PCR). Type-specific primers (6/11, 16 and 18; Amplicis HPV(R)) located in the E6 or E7 transforming region of HPV were used. HPV DNA was found in 2 of 18 cases (11%) of squamous cell carcinoma, in 1 of 4 cases of adenocarcinoma and in 2 of 7 cases of neuro-endocrine cancers. The two large cell undifferentiated carcinomas were HPV negative. There were three cases of HPV 6/11, one case of HPV 16, and one sample positive for HPV 6/11 and HPV 18. No any consistent morphologic change with HPV lesions could be observed whereas squamous metaplasia could be seen only in squamous cell carcinomas. The frequency of 11% among the squamous cell carcinomas is comparable to those previously reported in studies utilizing in situ hybridization. To our knowledge HPV DNA had never been detected previously in adenocarcinomas or neuro-endocrine tumors. This finding should be confirmed by the investigation of larger series, but suggests that HPV could play a role in carcinogenesis of different types of lung carcinoma, although at low frequency.

Bronchogenic carcinoma in patients seropositive for human immunodeficiency virus

The purpose of this report is to describe an association between bronchogenic carcinoma and HIV. Three HIV-seropositive patients are described who developed bronchogenic cancer (two large cell, one adenocarcinoma) before developing an AIDS-defining illness. A critical review of the literature revealed 22 other patients in which the association of HIV infection and lung cancer is reported. These patients are characterized by a relatively young age at diagnosis (median, 43 years) and prevalence of the adenocarcinoma subtype (13 of 25 patients). Twenty of 21 patients had a history of smoking. Among 21 patients for whom data were available, 6 patients (28 percent) had AIDS at time of diagnosis of lung cancer while 11 patients (55 percent) did not have AIDS or AIDS-related complex at diagnosis.

[Multiple primary cancers of the bronchi]

Sixty-six cases of multiple primary lung cancers were classified into 18 synchronous cancers and 48 metachronous cancers. They all occurred in tobacco-smoking men. The first group were symptomatic in 66% of cases, the second were symptomatic in 40% of cases. Six synchronous locations were unilateral and 12 were bilateral; 19 metachronous locations were ipsilateral and 29 were contralateral. Two cases had a third metachronous cancer. The resections of both tumours were performed in 11 out of 18 cases of synchronous cancers and 15 out of 48 cases of metachronous cancers. There were 2 deaths related to metachronous cancers. No patient with synchronous cancers survived 5 years after resection. One third of patients survived 5 years after resection of a metachronous cancer. Synchronous cancers represent an advanced stage. Metachronous cancers are diagnosed too late.