Paired Phase II Studies of Erlotinib/Bevacizumab for Advanced Bronchioloalveolar Carcinoma or Never Smokers With Advanced Non-Small-cell Lung Cancer: SWOG S0635 and S0636 Trials

BACKGROUND

Before mutation testing of the epidermal growth factor receptor (EGFR) gene was recognized as highly associated with the activity of EGFR tyrosine kinase inhibitors (TKIs), clinically defined patient populations with bronchioloalveolar carcinoma (BAC) and never smokers were identified as likely to benefit from EGFR TKIs. From preclinical and clinical data suggesting potentially improved efficacy with a combination of an EGFR TKI and the antiangiogenic agent bevacizumab, the Southwestern Oncology Group (SWOG) initiated paired phase II trials to evaluate the combination of erlotinib/bevacizumab in patients with advanced BAC (SWOG S0635) or never smokers with advanced lung adenocarcinoma (SWOG S0636).

MATERIALS AND METHODS

Eligible patients with BAC or adenocarcinoma with BAC features (SWOG S0635) or never smokers with advanced lung adenocarcinoma (SWOG S0636) received erlotinib 150 mg/day with bevacizumab 15 mg/kg until progression or prohibitive toxicity. Never smokers with BAC were preferentially enrolled to SWOG S0636. The primary endpoint for both trials was overall survival.

RESULTS

A total of 84 patients were enrolled in the SWOG S0635 trial and 85 in the SWOG S0636 trial. The objective response rate was 22% (3% complete response) in the SWOG S0635 trial and 50% (38% confirmed; 3% complete response) in the SWOG S0636 trial. The median progression-free survival was 5 and 7.4 months in the S0635 and S0636 trials, respectively. The median overall survival was 21 and 29.8 months, respectively. Toxicity consisted mainly of rash and diarrhea in both trials.

CONCLUSION

Although the field has moved toward molecular, rather than clinical, selection of patients as optimal candidates for EGFR TKI therapy, these results support the hypothesis that a subset of patients in whom erlotinib is particularly active could receive an incremental benefit from the addition of bevacizumab.

Tobacco smoking as a risk factor of bronchioloalveolar carcinoma of the lung: pooled analysis of seven case-control studies in the International Lung Cancer Consortium (ILCCO)

BACKGROUND

The International Lung Cancer Consortium (ILCCO) was established in 2004, based on the collaboration of research groups leading large molecular epidemiology studies of lung cancer that are ongoing or have been recently completed. This framework offered the opportunity to investigate the role of tobacco smoking in the development of bronchioloalveolar carcinoma (BAC), a rare form of lung cancer.

METHODS

Our pooled data comprised seven case-control studies from the United States, with detailed information on tobacco smoking and histology, which contributed 799 cases of BAC and 15,859 controls. We estimated the odds ratio of BAC for tobacco smoking, using never smokers as a referent category, after adjustment for age, sex, race, and study center.

RESULTS

The odds ratio of BAC for ever smoking was 2.47 (95% confidence interval [CI] 2.08, 2.93); the risk increased linearly with duration, amount, and cumulative cigarette smoking and persisted long after smoking cessation. The proportion of BAC cases attributable to smoking was 0.47 (95% CI 0.39, 0.54).

CONCLUSIONS

This analysis provides a precise estimate of the risk of BAC for tobacco smoking.

BAC consensus conference, November 4-6, 2004: epidemiology, pathogenesis, and preclinical models

INTRODUCTION

Human bronchioloalveolar carcinoma (BAC) is a disease with an evolving definition. "Pure" BAC, characterized by a bronchioloalveolar growth pattern and no evidence of stromal, vascular, or pleural invasion, represents only 2 to 6% of non-small cell lung cancer (NSCLC) cases, but up to 20% of NSCLC cases may contain elements of BAC. This imprecise definition makes it difficult to perform epidemiologic analyses or to generate accurate animal models. However, because BAC appears to behave clinically differently from adenocarcinoma, a better understanding of this disease entity is imperative.

METHODS/RESULTS

At the BAC Consensus Conference in 2004, our committee discussed issues relevant to BAC epidemiology, pathogenesis, and preclinical models.

CONCLUSIONS

Elucidation of molecular events involved in BAC tumorigenesis will allow for more precise epidemiologic studies and improved animal models, which will enable development of more effective treatments against the disease.

A new era for bronchioloalveolar carcinoma: current state of the art and recent advances in biologically targeted therapy

Bronchioloalveolar carcinoma is a fascinating and unusual variant of nonsmall-cell lung cancer that has a tendency towards an indolent course and to metastasize to the lung rather than distant organs. Chemotherapy has shown activity in advanced bronchioloalveolar carcinoma but response rates remain low. Epidermal growth factor receptor tyrosine kinase inhibitors have shown impressive activity against bronchioloalveolar carcinoma in trials. New data suggest that epidermal growth factor receptor mutations and gene copy number may predict subsets of patients who could most benefit from these novel agents. These new findings may point the way to a new era in which we can predict which patients will respond to epidermal growth factor receptor tyrosine kinase inhibitors and thus allow us to tailor therapy to the individual patient.

Emerging approaches to advanced bronchioloalveolar carcinoma

Bronchioloalveolar carcinoma (BAC) is a subtype of non-small cell lung adenocarcinoma that has distinct epidemiologic, histologic, radiographic, and clinical features. The strict pathologic definition requires an absence of any invasion through the basement membrane into pulmonary parenchyma, but there is a growing consensus based on recent clinical studies that this diagnosis should be considered to be based on the clinical features of diffuse ground-glass opacities with minimal or no extra-thoracic spread and histology demonstrating adenocarcinoma with a lepidic growth pattern characteristic of BAC, even if there is a component of invasive adenocarcinoma. Although unifocal or even potentially oligometastatic disease is appropriately treated with resection, advanced BAC is generally treated with systemic therapy. However, multifocal BAC may be indolent enough to follow asymptomatic patients without any systemic therapy if patients are comfortable with this approach, because the rate of disease progression may be slow enough to warrant no therapy for many months or even years. For patients who have symptoms and/or clear evidence of progression over a short interval, standard chemotherapy is appropriate, but I would consider treatment with the epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (TKI) erlotinib to be the most appropriate initial therapy. This is based on the well-documented activity of the EGFR TKIs erlotinib and gefitinib, the latter no longer commercially available in advanced BAC. Advanced BAC is now emerging as an area of significant research, and clinical trials are particularly appealing considerations for such patients.

Epidemiology of bronchioloalveolar carcinoma: improvement in survival after release of the 1999 WHO classification of lung tumors

PURPOSE

Classification changes for bronchioloalveolar carcinoma (BAC) by the WHO in May 1999 narrowed its definition. This study was undertaken in an attempt to characterize the impact of these changes on the epidemiology of BAC.

PATIENTS AND METHODS

This retrospective study involves data analysis from the population-based Cancer Surveillance Programs of three Southern California counties from 1995 to 2003. BAC cases diagnosed after May 1999 are compared with BAC cases before that time by clinicopathologic variables including survival.

RESULTS

Incident cases (11,969) of non-small-cell lung cancer (NSCLC) were analyzed, including 626 cases of BAC (5.2%). Median overall survival (OS) for BAC patients diagnosed after May 1999 (> 53 months) was significantly improved over median OS for BAC patients before May 1999 (32 months; P = .012). This survival benefit remained after adjustment for sex, smoking status, and stage at presentation (hazard ratio for time of diagnosis before May 1999 compared with a diagnosis after May 1999 = 1.43; P = .015). Median OS for non-BAC NSCLC patients diagnosed before May 1999 (9 months) did not differ from the median OS of such patients afterwards (10 months; P = .09).

CONCLUSION

This epidemiologic study is the first to demonstrate a survival advantage for BAC patients diagnosed after May 1999 compared with BAC patients diagnosed before this time-a finding that persists after adjustment for sex, smoking status, and stage at presentation. We believe that this observed survival benefit likely reflects changes in the revised 1999 WHO classification.

Bronchioloalveolar carcinoma: a review of the epidemiology, pathology, and treatment

Bronchioloalveolar carcinoma (BAC) is an important subtype of pulmonary adenocarcinoma. It has received increasing attention in recent years, due to its increasing incidence and its rate of sensitivity to epidermal growth factor-tyrosine kinase inhibitors (EGFR-TKIs). This article reviews the epidemiology, risk factors, pathology, clinical presentation, and treatment of this disease. Special focus is paid to the emerging role of oral EGFR-TKIs in Bronchioloalveolar cell carcinoma.

Surgical treatments for multiple primary adenocarcinoma of the lung

BACKGROUND

The aim of this study was to identify the clinical characteristics of multiple primary adenocarcinomas and to evaluate the efficacy of surgical treatments.

METHODS

Three-hundred sixty-nine patients who underwent pulmonary resection for adenocarcinoma from January 1994 to December 2002 were reviewed.

RESULTS

Thirty-one patients (8.4%) were determined to have multiple primary adenocarcinomas that could be detected on chest x-rays or computed tomography (CT). Twenty-six patients were synchronous and five patients were metachronous with a median interval of 59.0 months. Forty-nine (72.1%) of the total 68 lesions exhibited ground-glass opacity on high-resolution CT (HRCT). Pathologically well-differentiated adenocarcinoma with mixed bronchioloalveolar pattern was the most common subtype (39.7%). Taking into consideration pulmonary function, size, location, and HRCT findings of the lesions the procedures performed were lobectomy with mediastinal lymph-node dissection for 32 patients, segmentectomy with hilar node dissection for 8 patients, and wedge resection for 28 patients. Of 17 patients with bilateral synchronous cancers, simultaneous bilateral pulmonary resection was performed in 14 patients including simultaneous bilateral video-assisted thoracic surgery (VATS) in 11 patients. After a median follow-up period of 27.7 months, the 3-year overall survival rate was 92.9% and the 3-year disease-free survival rates of synchronous cancer and metachronous cancer were 77.9% and 100%, respectively.

CONCLUSIONS

The incidence of multiple primary adenocarcinomas was relatively common. Early radiographic detection and surgical excision could yield a favorable prognosis. The use of VATS, even for synchronous bilateral patients, was a safe and beneficial procedure.

Redefining Bronchioloalveolar Carcinoma

Bronchioloalveolar carcinoma (BAC) is a subtype of non-small cell lung cancer (NSCLC) with distinct clinical and pathologic features. Although BAC appears to be on a pathologic continuum with adenocarcinoma, the most recent World Health Organization (WHO) classification system has set stringent criteria for the diagnosis. Though malignant, these cancers tend to be peripheral and grow in a lepedic fashion along the alveolar septae without parenchymal invasion. This clear distinction based on histopathology allows for a more definite separation of the natural history and behavior of BAC in clinical studies. Recent clinical trials of molecular targeted anticancer therapies have led to a deeper understanding of the unique features of this cancer and suggest that BAC may require a different therapeutic paradigm from other NSCLCs.

Bronchioloalveolar Carcinoma in Small Pulmonary Nodules: Clinical Relevance

Increased use of chest computed tomography (CT) as well as improvements in CT resolution has led to increased detection of subcentimeter pulmonary nodules. Although the majority of these nodules are benign in etiology, a subset will harbor bronchioloalveolar carcinoma. The diagnosis of malignancy in this setting can be challenging to radiologists, surgeons, and occasionally pathologists as well. The challenge is compounded by a lack of knowledge about the natural course of these lesions--specifically, whether they represent life-threatening aggressive malignancies or indolent lesions of little or no consequence. Given the relative infrequency of these abnormalities, it will be essential to establish a sufficiently large database, to organize multi-institutional registries, and to collaborate on correlative studies. Only in this way will we be able to determine the clinical and molecular characteristics of these lesions and thus hopefully gain insight into their clinical relevance.

Bronchoalveolar Carcinoma: Current Treatment and Future Trends

Bronchoalveolar carcinoma (BAC) is a subtype of non-small-cell lung cancer (NSCLC) with unique clinical and pathologic characteristics. The most recent classification system defines BAC as a primary lung cancer that tends to be peripheral and grow in a lepedic fashion along the alveolar septae without parenchymal invasion. Most of the clinical information on BAC comes from retrospective institutional reviews; however, recent studies have focused more specifically on BAC. In particular, clinical trials of molecular-targeted anticancer therapies against the epidermal growth factor receptor have led to a deeper understanding of the distinct features of this cancer and suggest that BAC may require a therapeutic paradigm different from that of other NSCLCs.

The epidemiology of bronchioloalveolar carcinoma over the past two decades: analysis of the SEER database

Bronchioloalveolar carcinoma of the lung (BAC) is a subtype of adenocarcinoma of the lung. Although traditionally grouped with other non-small cell lung carcinomas (NSCLC), BAC has unique morphological features and clinical behavior such as bilateral lung involvement, indolent course and lack of association with smoking. Some epidemiologic studies report a significant increase in the incidence of BAC. We used the SEER database to compare the incidence, demographics, and overall survival of BAC patients as compared to other NSCLC types over the past two decades (1979-1998). Although the incidence of BAC has increased over the past two decades, BAC represents less than 4% of all NSCLC in every time period evaluated. The 1 year survival rate is significantly better for BAC patients relative to other histological subtypes of NSCLC. There has not been a marked increase in the incidence of BAC reported to SEER over the past 20 years.

[The occurrence of bronchioloalveolar lung cancer among our patients]

INTRODUCTION

One of the subtypes of pulmonary adenocarcinoma, bronchioloalveolar carcinoma (BAC), is mentioned as the lung cancer of non-smoking women. We have studied the clinical characteristics of BAC and its surgical treatment.

METHODS AND PATIENTS

Between 1992 and 2001, lung resections for BAC were performed on 101 patients: 55 men and 46 women, average age 59.7 years. Thirty-two of the patients were non-smokers, and 69 were active smokers. In 1992 the incidence of BAC was 17.5% of all adenocarcinomas, whereas in 2001 it had risen to 51.6%. The operations involved 76 lobectomies, 12 pulmonectomies, 11 wedge resections and 2 explorative thoracotomies.

RESULTS

The surgical mortality was 0.9%. The final histologic findings revealed that 82.1% of the tumours were in stages I or II, with 33.7% of the total in stage I/A. The average 5-year survival was 64.3%. Survival for women 75%, was significantly better than that for men, 51% (p=0.045). A significant difference was not found in the 5-year survival rate for multiple tumours or for BAC cases of different histological types.

CONCLUSIONS

The incidence of BAC, which occurs relatively frequently among women, and exhibits a relatively favourable course, has tended to increase in recent years. A majority of these tumours are removed in an early stage. The survival is not significantly poorer in the event of multiple tumours.

Pathology of human bronchioloalveolar carcinoma and its relationship to the ovine disease

Lung cancer is a leading cause of cancer with a poor prognosis. Bronchioloalveolar carcinoma (BAC) is a rare tumor that has always intrigued physicians. Since the last World Health Organization classification the pathology has been clarified; BAC per se is an adenocarcinoma with a pure bronchioloalveolar growth pattern and appears as an in situ alveolar adenocarcinoma. More usually BAC is a clinically recognizable entity presenting as multi-focal nodules evolving towards pneumonia associated with pulmonary shunting. Pathology is that of a multifocal mixed adenocarcinoma: bronchioloalveolar and papillar. Whatever the stage, survival is better than in other forms of non-small cell lung cancer (NSCLC). The true frequency of BAC is unknown, although it is a rare form of lung cancer; smoking cannot be excluded as a risk factor. It appears that p53 and ras genes are less often mutated than in other lung adenocarcinomas, suggesting that the cellular mechanisms involved are different. Ovine pulmonary adenocarcinoma (OPA) presents with the same symptoms as BAC in humans and is caused by a betaretrovirus Jaagsiekte sheep retrovirus. Very early on, clinical and histological similarities with human BAC were stressed. A recent series of OPA described, according to the third edition of the WHO classification for human lung cancer, mixed adenocarcinoma, BAC and papillary and/or acinar carcinoma. An immunohistochemical study suggested that some human pulmonary tumors (including BAC) may be associated with a Jaagsiekte sheep retrovirus-related retrovirus,but so far no molecular study has confirmed this observation. Thus, OPA is an exquisite model of carcinogenesis for human lung adenocarcinomas.

[Bronchoalveolar carcinoma]

Bronchoalveolar carcinoma is one of the four histologic subtypes of adenocarcinoma and its incidence is increasing. It grows in a lepidic fashion along the alveolar septa without invasive growth. The lack of invasive growth is an essential criterion based on data indicating that patients may be curable by surgical resection. The revised definition seems to be suitable for its solitary nodular form but less for multifocal or pneumonic-type form. High-resolution lung CT-scan is necessary to evaluate pulmonary involvement because of the high frequency of multifocal disease at initial presentation and because of the presence of ground glass opacity that could be one of the first manifestation of cancer bronchiolo-alvéolaireon CT. Therapeutic management does not differ from the one of non small cell lung cancer. Solitary nodules are treated by surgical resection with a good prognosis while multifocal and/or pneumonic forms are treated by systemic chemotherapy with a worse prognosis.

Small solitary pulmonary nodules (< or =1 cm) detected at population-based CT screening for lung cancer: Reliable high-resolution CT features of benign lesions

OBJECTIVE

We assessed thin-section CT features specific to benignity in solitary pulmonary nodules of 1 cm or smaller that were detected at population-based CT screening for lung cancer.

MATERIALS AND METHODS

Two reviewers independently made qualitative (presence or absence of lobulation, spiculation, air bronchogram, cavity, satellite lesions, pleural tag, concave margins, polygonal shape, and peripheral subpleural lesion) and quantitative (lesion size, percentage of ground-glass opacity areas, and two- and three-dimensional ratios of lesion) assessments in CT images of 72 nodules (25 lung cancers, seven atypical adenomatous hyperplasias, and 40 benign lesions). Optimal criteria specific to benignity were studied.

RESULTS

The prevalence of polygonal shape (p = 0.005 and p = 0.019, reviewer 1 and reviewer 2), peripheral subpleural lesion (p = 0.011 and p = 0.033), a predominantly solid lesion (p < 0.001 and p < 0.001), and three-dimensional ratios (p < 0.001 and p < 0.001) were greater in benign lesions than in malignancies. The prevalence of a predominantly solid lesion (p < 0.001 and p < 0.001) was greater in benign lesions than in atypical adenomatous hyperplasias, and the prevalence of a peripheral subpleural lesion (p = 0.004 and p = 0.012) was greater in atypical adenomatous hyperplasias than in malignancies. Using a single CT feature, polygonal shape and a three-dimensional ratio of greater than 1.78 showed 100% specificity for both reviewers. Among all combinations of CT findings specific to benignity, a combined criterion of a predominantly solid lesion and peripheral subpleural lesion or polygonal shape or the three-dimensional ratio attained the highest sensitivity (63% and 60%) for both reviewers.

CONCLUSION

A combined criterion of CT features was optimal for predicting benign pulmonary lesions.

Combined bilateral lung resections and off-pump coronary artery bypass grafting

We report herein a 74 year old man with angina who had an abnormal chest roentgenogram. Computed tomography of the chest showed a solitary 1.0-cm peripheral, noncalcified lesion in the apical segment of the left lower lobe and a 1.5-cm peripheral lesion in the posterior basal segment of the right lower lobe. Coronary angiography revealed the left anterior descending coronary artery to have a long 90% stenosis. We report here a case of a combined bilateral lung resection and off-pump coronary surgery though a midline sternotomy in a compromised lung function patient with both severe coronary artery disease and bilateral synchronous primary lung cancer.

Radiographic appearance of bronchoalveolar carcinoma in nine cats

Thoracic radiographs of nine cats with confirmed bronchoalveolar carcinoma (BAC) were reviewed retrospectively. Radiographic appearance of BAC was divided into three categories: mixed bronchoalveolar pattern, ill-defined alveolar mass, or mass with cavitation. In addition to these radiographic signs, all nine cats had evidence of some form of bronchial disease. Cavitary lesions were the most common finding (n = 5). In addition, three cats in this category had diffuse bronchointerstitial opacity and one cat had focal peribronchial cuffing. Five cats had either a mixed bronchoalveolar pattern with bronchiectasis (n = 3) or an ill-defined alveolar mass with peribronchial cuffing (n = 2). One cat had both a mixed bronchoalveolar pattern and a cavitary mass. Each of these nine cats had some form of bronchial disease (bronchointerstitial pattern, peribronchial cuffing, or bronchiectasis), which aids in the radiographic diagnosis of bronchoalveolar carcinoma and may represent airway metastasis.

Lung cancer associated with several connective tissue diseases: with a review of literature

The association between connective tissue disease (CTD) and malignancy has been an area of debate. Whether this relation is casual or causal, it would seem that the importance of their possible relationship is twofold. The purpose of this study is to describe the clinical features of lung cancer associated with several CTDs. Patients with CTD associated with lung cancer were retrospectively evaluated. A review of the clinical features of 153 reported cases from 1944 to the present was conducted. There were 82 females and 71 males, with a median age of 58. Histological types of lung cancer were as follows, bronchioloalveolar cell carcinoma (39 cases), adenocarcinoma (36), squamous cell carcinoma (28), small cell lung cancer (27), large cell carcinoma (6), others (8), and unknown (10). There was a relationship between smoking and development of lung cancer in patients with rheumatoid arthritis (RA) and polymyositis/dermatomyositis (PM/DM). The majority of patients with progressive systemic sclerosis (PSS) who developed lung cancer were female, with underlying interstitial fibrosis, and most tumors were of bronchioloalveolar cell or adenocarcinoma cell type. Patient characteristics were significantly different among the various groups of CTD associated with lung cancer.

Alpha1-antitrypsin deficiency allele carriers among lung cancer patients

Lung cancer (LC) and chronic obstructive pulmonary lung diseases (COPDs; including emphysema and chronic bronchitis) share a common etiology. Despite the known associations of alpha1-antitrypsin deficiency (alpha1AD) with COPD and COPD with LC, few studies examined the association of alpha1AD alleles and LC. We hypothesize that heterozygous individuals who carry a deficient allele of the alpha1AD gene Pi (protease inhibitor locus) are at an increased risk of developing LC. The Pi locus is highly polymorphic with >70 variants reported. There are at least 10 alleles associated with deficiency in alpha1-antitrypsin. Using an exact binomial test, we compared the alpha1AD carrier rate in 260 newly diagnosed Mayo Clinic LC patients to the reported carrier rate in Caucasians in the United States (7%). alpha1AD carrier status, determined by isoelectric focusing assay, was examined with respect to the history of cigarette smoking, COPD, and histological types. Thirty-two of the 260 patients (12.3%; 95% confidence interval, 8.6-16.9%) carried an alpha1AD allele, which was significantly higher than expected (P = 0.002). Twenty-four of the 32 carriers had allele S, 6 had allele Z, and 2 had allele I. Patients who never smoked cigarettes were three times more likely to carry a deficient allele (20.6%; P = 0.008), although smokers had a higher carrier rate (11.1%; P = 0.025) when compared with the 7% rate. Patients with squamous cell or bronchoalveolar carcinoma had a significantly higher carrier rate than expected (15.9% and 23.8%, P < or = 0.01, respectively). Our preliminary findings suggest that individuals who carry an alpha1AD allele may have an increased risk for developing LC, specifically squamous cell or bronchoalveolar carcinoma.

Time trend in the surgical management of patients with lung carcinoma

OBJECTIVE

The goal of the study was to analyze the histological and clinical trends in lung carcinoma and their influence upon the preoperative evaluation, surgical procedures and survival.

METHODS

We retrospectively reviewed the charts of 1079 consecutive patients who underwent surgery for primary lung carcinoma between 1977 and 1996 in our institution. Patients were divided into five equal 4-year periods according to the year of surgery (1977-1980; 1981-1984; 1985-1988; 1989-1992; 1993-1996).

RESULTS

Between 1977-1980 and 1993-1996, the incidence of squamous cell carcinoma significantly declined, whereas the incidence of adenocarcinoma and bronchioloalveolar carcinoma increased. During the same period, the proportion of squamous cell carcinoma visualized at bronchoscopy and the rate of preoperative histological diagnosis significantly decreased. An increasing proportion of lobectomy and less extended resection was associated with an increasing number of patients with stage I carcinoma. Meanwhile, the operative mortality significantly declined from 9 to 4% and the 5-year survival improved from 25 up to 40%.

CONCLUSION

Over the last two decades, the shift in histological distribution was associated with an increasing proportion of patients with stage I disease, a lower operative mortality and a better 5-year survival.

Primary lung neoplasia in a beagle colony

As part of long-term pulmonary carcinogenesis studies in dogs, it is important to analyze the incidence of spontaneous lung neoplasia. Primary lung carcinoma incidence was determined in two control populations of Beagle dogs observed for their life spans. One population comprised 216 dogs (112 males and 104 females) that were controls for life span studies, and another comprised 182 dogs (50 males and 132 females) that were retirees from a breeding colony. Forty lung neoplasms were noted in the 398 dogs; 35 neoplasms were carcinomas classified as papillary adenocarcinoma (20), bronchioloalveolar carcinoma (9), adenosquamous carcinoma (5), or bronchial gland carcinoma (1). The other five neoplasms were a malignant fibrous histiocytoma, three adenomas, and a fibroma. The crude incidence of lung carcinomas averaged for both populations was 8.8% (35/398) and was dominated by a relatively high incidence of lung neoplasia in aged dogs, those dying after the median life span of 13.6 years.

Bronchioloalveolar carcinoma

PURPOSE

To review bronchioloalveolar carcinoma (BAC).

MATERIALS AND METHODS

English language articles were identified through a Melvyl Medline Search (1966 to 1995) and through the bibliographies of selected articles.

RESULTS

An increase in BAC appears to be responsible for the observed rise in the incidence of adenocarcinoma of the lung. Patients with BAC tend to be younger at diagnosis, are more likely to be female, and less likely to be cigarette smokers when compared with other patients with non-small-cell lung cancer (NSCLC). The etiology of this disease is unclear, but multiple environmental insults have been implicated. There are three subtypes of BAC and the symptoms and prognosis of the disease depend on the subtype and extent of disease, but are generally similar to other histologic types of NSCLC. The radiographic differential diagnosis is broad and includes both benign and malignant diseases. The treatment approach to patients with BAC is similar to those with other types of NSCLC.

CONCLUSION

BAC appears to be increasing in incidence, especially in young, nonsmoking females. Three subtypes of the disease exist and are responsible for the variable clinical presentations. Further epidemiologic investigation is needed to elucidate the etiology and pathogenesis of this unique disease.

Time trend and the age-period-cohort effect on the incidence of histologic types of lung cancer in Connecticut, 1960-1989

BACKGROUND

Recent epidemiologic studies have suggested changing patterns of lung cancer incidence by histologic type. The observed time trends have been attributed to a change in the rate of cigarette smoking, changes in exposure to new environmental carcinogens, and changes in the criteria for the histopathologic diagnosis of lung cancer. The current study was designed to examine the incidence patterns of lung cancer by histologic type in Connecticut and to use this information to project the future trend of the disease in this population.

METHODS

This study was based on all the lung cancer cases reported to the Connecticut Tumor Registry between 1960 and 1989. On the basis of this data set, crude and age-adjusted incidence rates of lung cancer were calculated by histologic type for each sex. The age-specific incidence rates are presented by calendar year and cohort year of birth. A regression model was used to identify birth cohort, period, and age as determinants of the observed time trends.

RESULTS

For the overall age-adjusted incidence rates, squamous cell carcinoma and small cell carcinoma have stabilized in men, whereas they are still increasing in women. The incidence of adenocarcinoma has been increasing in both men and women, but there has been a much sharper incidence among females since the mid-1970s. An examination of age-specific incidence rates by birth cohort and the results from age-period-cohort modeling indicate that incidences of all three major histologic types of lung cancer in the recent birth cohorts either have started decreasing (squamous cell carcinoma) or shown a clear reduction in the rate of increase (adenocarcinoma and small cell carcinoma). This study, however, did not indicate an increase of bronchoalveolar lung carcinoma, which was reported by other clinically based studies.

CONCLUSION

While the overall age-adjusted incidence rates showed different incidence patterns for different histologic types of lung cancer, a decreasing or stabilized rate for all three major histologic types of lung cancer was observed in recent birth cohorts in both males and females. The observed incidence pattern is consistent with smoking trends over time including changes in smoking prevalence and the consumption of low tar and filter cigarettes. It is expected that if the current trend in tobacco smoking continues and if there are no major changes in other risk factors for lung cancer, a forthcoming stabilization or decrease in the rate of lung cancer incidence for all major histologic types (including adenocarcinoma) in both sexes in Connecticut could be anticipated.

[Bronchiolo-alveolar carcinoma. The computed tomographic picture and histological correlations]

Twenty-one CT examinations of 18 patients with a known bronchioloalveolar carcinoma in the lung were retrospectively reviewed to describe the CT features of bronchioloalveolar carcinomas. Surgical specimens were available in 13 cases in which CT-histologic correlation was also obtained. In 5 patients the diagnosis was made with cytology and confirmed with radiologic-clinical follow-up. Three patients were reexamined for relapses 6-20 months after the resection of a localized carcinoma. Carcinomas exhibited 3 radiologic patterns: a) solitary pulmonary nodule (11 cases), b) mass or pulmonary consolidation (3 cases) and c) multicentric or diffuse disease (7 cases). Solitary nodular bronchioloalveolar carcinomas were associated with irregular or spiculated margins in 9 of 11 patients. In some cases internal inhomogeneity due to bubble-like radiolucencies was demonstrated. At pathology, bubble-like radiolucencies correlated with air-containing cystic spaces lined by neoplastic epithelium or patent and dilated bronchi. Some nodules exhibited linear and serpentine internal radiolucencies. Pathology demonstrated them to be consistent with patent intratumoral bronchioles (air bronchiologram) and air-containing neoplastic glandular spaces, respectively. In two cases a perinodular ground-glass halo was demonstrated surrounding the nodule (CT halo sign), due to perinodular lepidic tumor growth. Massive or ground-glass opacity involving a pulmonary segment or a lobe was another CT pattern of bronchioloalveolar carcinoma. An air bronchogram was usually demonstrated within the lesion. In the mucinous type of bronchioloalveolar carcinoma, pulmonary consolidations had a low CT value because of the large amount of intratumoral mucus. The diffuse type of tumor presented as multiple pulmonary nodules or multiple pulmonary consolidations, or both. In two cases multiple nodules were associated with carcinomatous lymphangitis. In conclusion, bronchioloalveolar carcinoma should be considered in the differential diagnosis of solitary pulmonary nodules, multiple pulmonary nodules and chronic alveolar opacities. The diagnosis of a bronchioloalveolar carcinoma is of great value since surgery can help nearly 70% of the patients at this stage recover.

Rising incidence of bronchioloalveolar lung carcinoma and its unique clinicopathologic features

BACKGROUND

Bronchioloalveolar lung carcinoma (BAC) is a unique type of lung cancer with distinguishing pathologic, biologic, epidemiologic, demographic, and perhaps etiologic features.

METHODS

The authors investigated and analyzed all of the cases of pathologically confirmed BAC seen at our institution in the hope of discovering new or confirming known features of this disease.

RESULTS

When cases of BAC expressed as a percentage of total lung cancers were analyzed in successive 5-year periods from 1955 to 1990, BAC rose from less than 5% to 24.0% (P < 0.001). Much of the increase in BAC occurred in women, as evidenced by a male-to-female ratio that wavered around unity. The mean age of BAC adenocarcinoma patients was 59.2 +/- 11.5 years, compared to 64.1 +/- 13.5 years for non-BAC adenocarcinoma (P < 0.05). BAC also contrasted with other forms of lung cancer by exhibiting a relatively high incidence of multifocality (25% versus 5%) (P < 0.001). There was an association between histologic subtype of BAC and pattern of pulmonic involvement. The mucinous subtype was more strongly associated with diffuse pulmonic involvement, and the sclerotic subtype was more strongly associated with multifocal involvement (P < 0.001). Furthermore, BAC cases exhibited a 20% incidence of dedifferentiation into patterns of poorly differentiated adenocarcinoma, a feature that was more associated with the mucinous and sclerotic subtypes (P < 0.05).

CONCLUSIONS

The emergence of BAC as a prominent type of lung cancer should stimulate new basic laboratory and case-control studies to elucidate further the natural history and etiology of this unique disease.

"CT angiogram sign" in obstructive pneumonitis and pneumonia

OBJECTIVE

The "CT angiogram sign" in dynamic pulmonary CT consists of enhanced branching pulmonary vessels in a homogeneous hypoattenuating consolidation of lung parenchyma and is reportedly useful for diagnosing lobar bronchioloalveolar cell carcinomas.

MATERIALS AND METHODS

To identify cases exhibiting the CT angiogram sign, we retrospectively reviewed the reports of 5,500 dynamic incremental CT examinations of the chest.

RESULTS

We identified the CT angiogram sign in five patients with obstructive pneumonitis due to lung tumors and four patients with pneumonias.

CONCLUSION

The CT angiogram sign can be observed in pulmonary consolidation of varying etiologies.

Epidemiology of bronchioloalveolar carcinoma

Descriptive features of bronchioloalveolar carcinoma (BAC) are presented using Surveillance, Epidemiology and End Results Program population-based incidence data from 1973 through 1987, along with risk factors from histologically confirmed cases of BAC identified in a hospital-based case-control study conducted in Louisiana between 1979 and 1982. Compared to the rising incidence of lung cancer overall, BAC rates have remained relatively constant, accounting for less than 3% of all lung cancer. BAC incidence rates were higher in males, yet it explained proportionately more of the total lung cancer incidence in females. In the case-control study, 21 of the 33 cases originally ascertained from hospital pathology records were histologically confirmed as BAC. Most cases smoked cigarettes, with a 4-fold risk for ever smoking. Risks tended to increase with smoking intensity (reaching 10-fold for more than 1.5 packs/day) and duration (reaching 5-fold for more than 45 years of smoking). Following 10 or more years of employment, there was a 4-fold risk associated with motor freight occupations, along with nonsignificant excesses among construction workers, petroleum manufacturers, and sugar cane farmers. Cases were more likely than controls to have had emphysema or to have had a close family member with lung cancer. Although based on small numbers, this study suggests that BAC shares many of the epidemiological characteristics of lung adenocarcinoma.

The changing pattern of lung carcinoma

In a study of 505 cases of lung carcinoma from a period in which there was a significant change in tobacco-smoking habits, a dramatic shift in the histologic type and location of the lung tumors was observed. Peripheral tumors, found in 30.7% of the carcinomas occurring before 1978, were found in 42% of the carcinomas from 1986 to 1989. The corresponding decrease in the centrally originating bronchial carcinoma was from 69.3% to 57.3%. The greatest change in histologic cancer type was that the incidence of bronchioloalveolar carcinoma more than doubled from 9.3% in the earlier period to 20.3% percent in the 1986-to-1989 period. Corresponding to the decreasing incidence of lung carcinoma, there is a decrease in cancers related to cigarette smoking. A study of cases of lung carcinoma among nonsmokers and former smokers showed a decreased incidence of the bronchogenic cancers and an increase of cancer occurring in the peripheral lung parenchyma. This finding should be validated in other population-based studies, and if confirmed, new studies should be undertaken in an attempt to discover the factors that play a role in the development of such cancers. As an example, viral oncogenes may be a possibility. Viruses were suggested in the past as being related to the development of some of these tumor types.

[Roentgeno-morphologic forms of bronchioloalveolar cancer]

The paper is concerned with the description of clinical, x-ray and morphological investigation of 123 bronchoalveolar cancer patients. Three types of this disease were defined: nodular (homogeneous and nonhomogeneous), pneumonia-like (infiltrative and infiltrative-nodular) and mixed (focal-disseminated, focal-nodular and focal-infiltrative). These types of bronchoalveolar cancer are most probably stages of the same tumor process. Clinical and x-ray signs of each type showed correlation with a morphological picture of a tumor. Shadow nonhomogeneity as one of the main x-ray signs of bronchoalveolar cancer was shown to be determined by the "alveolar" structure of a tumor, a tendency to the formation of small cavities, filled with viscous mucosa and air. Correct clinical and x-ray diagnosis in all types of bronchoalveolar cancer (before the use of the morphological methods) was established in 45.5% of the patients.

[Anatomo-clinical study of 102 cases of primary lung cancer]

The authors do a clinical anatomic study showing 102 cases of lung primitives cancers to be diagnose in 60% cases on biopsy and 40% on operation'piece. The matter in boundless majority of cases is carcinoma 92%, themselves overlooked by squamous cells carcinoma 55%, forwarded by adenocarcinoma 20%, small cells carcinoma represent 11% of cases and large cells carcinoma 7%. The mean age of occur is 55 years and any cases of carcinoma is observed at persons under 30 years of age. 94% of person are masculine. The majority of tumors 58% cases present themselves as bulky masses exceeding 6 cm of diameter. The authors insist in this study on necessity of early diagnosis when the therapeutic will be curative.

[Bronchioalveolar carcinoma]

A study of 21 patients suffering from bronchioalveolar carcinoma and 1028 comparable cases of the literature is presented. By this we gained statistical data concerning radiological and clinical manifestations of this rare tumour. However, radiological signs estimated to be typical of this carcinoma, like "rabbit ear sign" and positive "air bronchogram" are too rare to be really helpful for putting up the diagnosis. At time of diagnosis the mean age was 58 years. Men are hardly more frequently concerned than women. Smoking seems to have no aetiological significance. The most common clinical symptom was chronic cough followed by chest pain. A large amount of sputum--a symptom which sometimes has been estimated to be typical of this tumour--occurred only very rarely.

A clinical statistical analysis of 4,931 lung cancer cases in Japan according to histological type--field study results. A report from the Japanese Joint Committee of Lung Cancer Associated with the TNM System of Clinical Classification (UICC)

From records of 4,931 cases of lung cancer during the period 1975-1977, a clinical statistical analysis according to histological type was performed. Epidermoid carcinoma accounted for 46.6% of male cases and 18.8% of female cases, while adenocarcinoma was the histological type in 61.2% of female cases and 30.3% of male cases. Five-year survival rates were 14.4%, 14.4%, 11.9%, 5.4% and 1.3% for epidermoid carcinoma, adenocarcinoma, large cell carcinoma, and small cell carcinoma of the intermediate cell type and oat cell type, respectively. Of the adenocarcinoma cases, 32.9% were in Stage Ia, and 52.1% showed overall operability and 43.0% curative operability. For small cell carcinoma of the intermediate cell type and oat cell type, 75% and 79% of cases were in Stages III and IV, respectively. The operability of oat cell carcinoma was 15.2%; 72.2% underwent radiation, and 84.8% underwent chemotherapy.

Benign tumors of the lung and bronchus

Benign tumors of the lung and bronchus are a heterogeneous group of lesions that usually present as asymptomatic, solitary, peripheral lung nodules or, less commonly, as endobronchial lesions causing obstructive symptoms. All endobronchial lesions should be removed surgically to alleviate symptoms and to prevent destruction of distal lung tissue. Parenchymal lesions may present challenging problems in clinical diagnosis and management. Most patients will ultimately require thoracotomy for histologic confirmation of benignity. It is probable that newer diagnostic procedures will allow a more accurate nonoperative diagnosis in certain patients in the near future. At the present time, expeditious limited thoracotomy affords a safe, rapid, and effective treatment for patients with a benign tumor of the lung or bronchus.

The changing histopathology of lung cancer: a review of 1682 cases

We have reviewed the histopathology of lung cancer patients seen over the past 13 years at RPMI. Assessment of this data indicates that adenocarcinoma is becoming progressively more prevalent as related to the other forms of lung cancer. Factors which in part may account for this increased prevalence are: 1) changes in criteria for reading histopathology of lung cancer, particularly since 1967; 2) the increased incidence of lung cancer among the female population who have a propensity for adenocarcinoma; and 3) occupational and environmental factors. In 1974 adenocarcinoma for the first time became the most prevalent type of lung cancer at RPMI. Whatever the reason, if our data are truly representative of a national trend, adenocarcinoma will soon become the most prevalent type of lung cancer in the United States. This fact may result in an increasing death rate since the present 18-month survival rate for adenocarcinoma is substantially less than for squamous cell carcinoma, which has in the past been the prevalent form of the disease. As the smoking habits of women more closely approximate those of men, we expect that the incidence and mortality of lung cancer will prove to be quite similar in both sexes.

Bronchial cancer - a clinical and pathological study. II. Frequency according to age and sex during a 12-year period

A necropsy series of bronchial cancer combined with a retrospective clinical study comprising 747 cases of bronchial cancer from a defined population is described. A significant successive increase in the frequency of bronchial cancer during the 12-year period 1958-1969 was found. The increase during three successive 3-year periods will be as much as 45, 86 and 146%, respectively, if the 1958-1960 frequency is set to 100%. In contrast to many other investigations this increase was found in both women and men (the relative increase was exactly the same in both sexes) and for both Group I and Group II tumours. The ratios between men and women and between Group I and Group II tumours in the present material were thus constant throughout the investigation. This may be explained by the assumption that the female population today has smoked cigarettes for a sufficiently long period to stimulate the development of bronchial cancer and that there seems also to be a correlation between Group II tumours and cigarette smoking.

A retrospective study of lung cancer in Bombay

This is a retrospective study of 520 patients with lung cancer, seen at the Tata Memorial Hospital between 1963 and 1970. Matched controls were obtained from those patients who came to the hospital within the same period and who were diagnosed as not having cancer. The patients and controls were matched for age, sex and community. As reported in other studies, an association was found between smoking habit and lung cancer. The relative risk of all types of smokers to non-smokers is 2·45, of bidi smokers 2·64 and of cigarette smokers 2·23. There is a preponderance of the group of epidermoid carcinomata among smokers as against adenocarcinomata. The probable reasons for the reported low incidence of lung cancer in this population have been discussed.