The correlation of emphysema or airway obstruction with the risk of lung cancer: a matched case-controlled study.

A matched case-controlled study was conducted to determine if airway obstruction or emphysema were associated with an increased risk of lung cancer. Lung cancer cases (n=24) were identified through a low-dose spiral computed tomography (CT) screening trial from 1,520 participants. Four controls without lung cancer were selected for each case from the participants and matched by sex, age and smoking history. Emphysema was assessed by quantitative CT analysis. Conditional logistic regression was employed to assess results of spirometry and CT quantitative analysis as potential risk factors for lung cancer. The likelihood of lung cancer was found to be significantly increased for those with forced expiratory volume in one second (FEV1) < or = 40% of predicted. The results suggested that a lower percentage of predicted FEV1 was indicative of lung cancer. No compelling evidence was found to suggest that the percentage of emphysema was associated with lung cancer. These results suggest an increased risk of lung cancer associated with airway obstruction. However, percentage of emphysema as determined by computed tomography was not associated with an increased risk of lung cancer.

Pulmonary Langerhans cell histiocytosis presenting as a solitary nodule.

Solitary pulmonary nodules are an uncommon manifestation of pulmonary Langerhans cell histiocytosis (PLCH). We describe a 45-year-old male cigarette smoker who presented with an asymptomatic solitary pulmonary nodule that showed histologic and immunophenotypic characteristics of PLCH. Twenty-one years after excision of the nodule, at the age of 66 years, he is asymptomatic with a new contralateral lung nodule but no evidence of interstitial disease. The new nodule has remained unchanged after 36 months of observation. This case affirms that PLCH can occasionally cause solitary lesions, which should not be interpreted as a harbinger of interstitial lung disease. Isolated PLCH should be included in the differential diagnosis of unusual solitary pulmonary nodules.

A consensus statement of the Society of Thoracic Radiology: screening for lung cancer with helical computed tomography.

This consensus statement by the Society of Thoracic Radiology is a summary of the current understanding of low dose computed tomography (CT) for screening for lung cancer. Lung cancer is the most common fatal malignancy in the industrialized world. Unlike the next three most common cancers, screening for lung cancer is not currently recommended by cancer organizations. Improvements in CT technology make lung screening feasible. Early prevalence data indicate that about two-thirds of lung cancers that are detected by CT screening are at an early stage. Other data support the postulate that patients with lung cancers detected at this early stage have better rates of survival. Whether this will translate into an improved disease specific mortality is yet to be demonstrated. The suggested technical protocols, selection criteria, and method of handling the numerous benign nodules that are detected are discussed. It is the consensus of this committee that mass screening for lung cancer with CT is not currently advocated. Suitable subjects who wish to participate should be encouraged to do so in controlled trials, so that the value of CT screening can be ascertained as soon as possible.

Diagnosis of pulmonary embolism with use of computed tomographic angiography.

Pulmonary embolism (PE) is a common diagnostic problem, particularly in hospitalized patients. It remains a frequent cause of unexpected deaths. Traditionally, the diagnostic work-up for suspected PE has centered on the use of ventilation-perfusion (V-P) radionuclide lung scanning. However, V-P scanning does not provide adequate confirmation or exclusion of the diagnosis in the majority of patients who undergo this test. Although published guidelines advise further diagnostic testing after nondiagnostic V-P scans, clinicians infrequently perform such testing, and management decisions are commonly based on clinical judgment. In recent years, there has been an increasing interest in the use of computed tomographic (CT) angiography in the diagnostic evaluation of patients with suspected PE. Although there are unresolved issues regarding its sensitivity in detecting small peripheral emboli, CT angiography is more accurate than V-P scanning in the diagnosis of PE and yields other intrathoracic diagnoses. Herein we summarize the problems with the traditional approach centered on the use of V-P scanning in the diagnosis of PE and propose an alternative diagnostic strategy based primarily on the use of CT angiography.

Nonspecific interstitial pneumonia: variable appearance at high-resolution chest CT.

PURPOSE: To describe the computed tomographic (CT) findings in patients with nonspecific interstitial pneumonia (NSIP) and to compare these with the CT findings of other chronic infiltrative lung diseases. MATERIALS AND METHODS: Findings in 50 patients with biopsy-proved NSIP and a CT scan were reviewed by two thoracic radiologists in consensus. After the findings were described, the observers judged whether the findings were compatible with previously published descriptions of NSIP or whether the findings would support the diagnosis of a different chronic infiltrative lung disease. RESULTS: Eleven (22%) of the 50 patients had CT findings that were compatible with previous descriptions of NSIP. Sixteen (32%) patients had CT findings that were more compatible with usual interstitial pneumonia. The other 23 (46%) patients had findings that were nondiagnostic or most compatible with the diagnosis of another chronic infiltrative lung disease. CONCLUSION: Contrary to previously published articles, there are a wide variety of CT findings in cases of NSIP.

Pulmonary involvement with Erdheim-Chester disease: radiographic and CT findings.

OBJECTIVE: We determined the chest radiographic and CT findings of Erdheim-Chester disease with pulmonary involvement. MATERIALS AND METHODS: We retrospectively reviewed the radiologic images of 15 patients with biopsy-proven Erdheim-Chester disease. Nine patients had chest radiographic images and CT scans that were available for review. Six men and three women were studied (age range, 25-70 years; mean age, 56 years). Two radiologists interpreted all images by consensus. Lung parenchyma was assessed for the type and distribution of disease. Bronchi, pleurae, hila, and mediastinal and extrathoracic structures were evaluated for abnormalities. Pathologic specimens from all patients were reviewed and correlated with radiologic findings. RESULTS: Eight of nine patients had thoracic images with abnormal findings. The most common radiographic pattern was reticular interstitial opacities with fissural and interlobular septal thickening. CT revealed regions of ground-glass attenuation and centrilobular nodular opacities. Typically, extrapulmonary findings included pleural effusions (6/8 patients), pericardial fluid or thickening (4/8), and extrathoracic infiltrative soft-tissue masses (4/8). CONCLUSION: The most common findings of Erdheim-Chester disease with pulmonary involvement include an interstitial process characterized by smooth interlobular septal thickening and centrilobular nodular opacities, fissural thickening, and pleural effusions. On CT, six of nine patients had pericardial fluid and thickening or extrathoracic soft-tissue masses. Such findings are characteristic of Erdheim-Chester disease with pulmonary involvement. Definitive diagnosis requires correlating skeletal findings and lung biopsy findings.

Lung nodule enhancement at CT: multicenter study.

PURPOSE: To test the hypothesis that absence of statistically significant lung nodule enhancement (< or =15 HU) at computed tomography (CT) is strongly predictive of benignity. MATERIALS AND METHODS: Five hundred fifty lung nodules were studied. Of these, 356 met all entrance criteria and had a diagnosis. On nonenhanced, thin-section CT scans, the nodules were solid, 5-40 mm in diameter, relatively spherical, homogeneous, and without calcification or fat. All patients were examined with 3-mm-collimation CT before and after intravenous injection of contrast material. CT scans through the nodule were obtained at 1, 2, 3, and 4 minutes after the onset of injection. Peak net nodule enhancement and time-attenuation curves were analyzed. Seven centers participated. RESULTS: The prevalence of malignancy was 48% (171 of 356 nodules). Malignant neoplasms enhanced (median, 38.1 HU; range, 14.0-165.3 HU) significantly more than granulomas and benign neoplasms (median, 10.0 HU; range, -20.0 to 96.0 HU; P < .001). With 15 HU as the threshold, the sensitivity was 98% (167 of 171 malignant nodules), the specificity was 58% (107 of 185 benign nodules), and the accuracy was 77% (274 of 356 nodules). CONCLUSION: Absence of significant lung nodule enhancement (< or = 15 HU) at CT is strongly predictive of benignity.

Lung nodules: dual-kilovolt peak analysis with CT--multicenter study.

PURPOSE: To test the following hypothesis: The greater the increase in the mean computed tomographic (CT) number of a radiologically indeterminate lung nodule from the CT number on a 140-kVp CT image to that on an 80-kVp CT image, the more likely the nodule is benign (ie, contains calcium). MATERIALS AND METHODS: Two hundred forty indeterminate lung nodules were prospectively studied at four institutions: Mayo Clinic Scottsdale, Ariz (n = 160); Mayo Clinic Rochester, Minn (n = 50); Shiga Health Insurance Hospital, Otsu, Japan (n = 25); and Duke University Medical Center, Durham, NC (n = 5). Of the 240 nodules, 157 met the entrance criteria for this study and had a diagnosis. All nodules included were solid, 5-40-mm diameter, relatively spherical, homogeneous, and without visible evidence of calcification or fat. Each nodule was evaluated by using 3-mm-collimation, nonenhanced CT scans with both 140- and 80-kVp x-ray beams. RESULTS: There were 86 (55%) benign and 71 (45%) malignant nodules. The median increase in the nodule mean CT number from the CT number on 140-kVp images to that on 80-kVp images was 2 HU for benign nodules and 3 HU for malignant nodules. This difference was not statistically significant. The area under the receiver operating characteristic curve was 0.505. CONCLUSION: Dual-kilovolt peak analysis with current CT technology does not appear to be helpful in the identification of benign lung nodules.

Radiologic findings of bronchogenic carcinoma with pulmonary metastases at presentation.

PURPOSE: To describe the radiologic findings in patients with primary bronchogenic carcinoma and pulmonary metastases at presentation. MATERIALS AND METHODS: A retrospective review of patients with bronchogenic carcinoma who at presentation had pulmonary metastases. RESULTS: Fourteen (52%) men and 13 (48%) women with a mean age of 60 years were identified. Adenocarcinoma was the most common histology (70%). The number of nodules varied, although 78% of patients had greater than 50 nodules. Nodules size ranged from 2 to 30 mm, but 82% of patients had nodules less than 10 mm in diameter. Mediastinal lymphadenopathy was seen in 41% of patients, and pleural disease in 44% of patients. Only 37% had radiologic evidence of extrathoracic disease, with bone metastases (30%) being the most common. CONCLUSION: Multiple pulmonary nodules may be the presenting thoracic manifestation of primary bronchogenic carcinoma, with patterns of metastases and survival rates similar to other stage IV patients.

Suspected non-small cell lung cancer: incidence of occult brain and skeletal metastases and effectiveness of imaging for detection--pilot study.

PURPOSE: To estimate the incidence of occult metastases to the brain and skeleton in patients suspected of having non-small cell lung cancer (NSCLC) (stage higher than T1Nomo) with surgically resectable disease, to assess the accuracy of screening magnetic resonance (MR) imaging and radionuclide bone scanning for help in identifying occult metastases, and to determine the effectiveness of a high dose of MR contrast material. MATERIALS AND METHODS: Twenty-nine patients suspected of having NSCLC localized to the lung or to the lung and regional nodes underwent preoperative MR imaging with contrast material enhancement and radionuclide bone scanning for detection of brain or skeletal metastases. Patients were followed up for 12 months to determine the incidence of clinical metastatic disease. RESULTS: Eight (28%) patients had occult metastatic disease to the brain or skeleton. Brain metastases were identified on MR images in five of six patients. Bone metastases were identified on MR images in four of five patients and on bone scans in three of five patients. MR imaging was no more accurate than bone scanning for skeletal evaluation. A high dose of MR contrast material allowed detection of more metastases and of small lesions. CONCLUSION: Contrast-enhanced MR imaging of the brain is indicated for the exclusion of brain metastases in patients with clinically operable known or possible NSCLC and a large (> 3-cm) lung mass. Skeletal imaging may be indicated if an isolated brain metastasis is detected.

Solitary pulmonary nodules: clinical prediction model versus physicians.

OBJECTIVE: To determine whether a clinical prediction model developed to identify malignant lung nodules based on clinical data and radiologic lung nodule characteristics could predict a malignant lung nodule diagnosis with higher accuracy than physicians. MATERIAL AND METHODS: One hundred cases were obtained by using a stratified random sample from a retrospective cohort of 629 patients with newly discovered 4- to 30-mm radiologically indeterminate solitary pulmonary nodules (SPNs) on chest radiography. A chest radiologist, pulmonologist, thoracic surgeon, and general internist made predictions of a malignant lesion and recommendations for management (thoracotomy, transthoracic needle aspiration biopsy, or observation) on the basis of radiologic and clinical data used to develop the clinical prediction rule. The predictions of a malignant lung nodule were compared with the probability of malignant involvement from a previously validated clinical prediction model to identify malignant nodules on the basis of three clinical characteristics (age, smoking status, and history of cancer greater than or equal to 5 years previously) and three radiologic characteristics (nodule diameter, spiculation, and upper lobe location). RESULTS: Receiver operating characteristic analysis showed no significant difference between the logistic model and the physicians' predictions. Calibration curves revealed that physicians overestimated the probability of a malignant lesion in patients with low risk of malignant disease by the prediction rule; this finding suggests a potential for the decision rule to improve the management of patients with SPNs that are likely to be benign. CONCLUSION: The prediction model was not better than physicians' predictions of malignant SPNs. The prediction rule may have potential to improve the management of patients with SPNs that are likely to be benign.

Erdheim-Chester disease: clinical, radiologic, and histopathologic findings in five patients with interstitial lung disease.

Erdheim-Chester disease is a clinicopathologic entity defined by a characteristic pattern of symmetric osteosclerosis caused by an infiltrate of mononuclear cells that include prominent numbers of foamy histiocytes. About half of patients have extraskeletal manifestations, including involvement of the hypothalamus/posterior pituitary, orbit, retroperitoneum, skin, lung, and heart. Pulmonary involvement is an uncommon but important manifestation of Erdheim-Chester disease because it causes significant morbidity and mortality. A review of the Mayo Clinic files produced four patients with confirmed Erdheim-Chester disease in whom lung biopsy had been performed. One additional patient was included from the University of Pittsburgh. Four patients were women. The mean age was 53.6 years (range 25-70 years). All patients had bilateral and symmetric sclerotic bone lesions characteristic of Erdheim-Chester disease, although in three the skeletal abnormalities were discovered only after lung biopsy. Four patients had dyspnea, and one also had a dry cough. One patient died 17 months after diagnosis. Chest radiographs showed diffuse interstitial infiltrates in all patients, with an upper zone predominance in three. Thoracic computed tomography (CT) scans showed thickening of the visceral pleura and interlobular septa with patchy associated fine reticular and centrilobular opacities and ground glass attenuation. Lung biopsy specimens showed an infiltrate of foamy histiocytes, lymphocytes, and scattered Touton giant cells with associated fibrosis in a striking lymphatic distribution. The infiltrate involved visceral pleura, interlobular septa, and bronchovascular bundles. Immunohistochemical stains were positive for CD68 in all cases and S-100 protein in four cases. Stains for CD1a were consistently negative. Ultrastructural studies in one case showed no Birbeck granules. Although in bone the histologic features of Erdheim-Chester disease may overlap with Langerhans' cell histiocytosis, its expression in the lung is distinct. Lung involvement in Erdheim-Chester disease has emerged as a unique radiographic and histologic entity.

Advanced multiple beam equalization radiography: receiver operating characteristic comparison with screen-film chest radiography.

OBJECTIVE: To test the hypothesis that the advanced multiple beam equalization radiography (AMBER) imaging system is superior to conventional chest radiography in the demonstration of diffuse infiltrative lung disease, emphysema, pulmonary nodules, calcification within nodules, and mediastinal or hilar masses and lymphadenopathy. MATERIAL AND METHODS: The study involved 115 patients, each of whom underwent chest computed tomography (CT), AMBER, posteroanterior chest radiography, and conventional posteroanterior stereoscopic chest radiography (two films). All radiographs were obtained with the InSight Thoracic Imaging System. Four chest radiologists independently analyzed the 115 AMBER studies, 115 unpaired single conventional radiographs (a single film from a stereoscopic pair), and 115 stereoscopic conventional radiographs (2 films) for the presence of diffuse infiltrative lung disease, emphysema, pulmonary nodules, calcification within nodules, and mediastinal or hilar masses and lymphadenopathy. For each abnormality detected, the radiologists described their level of confidence based on a scale of 1 to 5. The 115 CT examinations were interpreted by consensus among 3 of the chest radiologists. The CT results were considered the standard. Receiver operating characteristic (ROC) techniques were used for statistical analysis. RESULTS: No statistically significant differences were found with ROC techniques between the AMBER system and single or stereoscopic conventional screen-film radiography for the abnormalities studied. CONCLUSION: We noted no clinically significant difference between AMBER and either single or stereoscopic conventional screen-film radiography in this prospective study of 115 patients in which CT (performed within 1 week of both radiographic examinations) was the standard.

Colchicine versus prednisone in the treatment of idiopathic pulmonary fibrosis. A randomized prospective study. Members of the Lung Study Group.

Twenty-six symptomatic subjects with clinical evidence plus either high-resolution computed tomography (HRCT, n = 25) or open-lung biopsy (OLB, n = 1) patterns typical for idiopathic usual interstitial pneumonia (idiopathic UIP) were entered into a randomized prospective treatment trial using high-dose prednisone (n = 12) versus colchicine (n = 14). The minimum dose of prednisone used was 60 mg/d for 1 mo, tapered to 40 mg/d over the second month, tapered to 40 mg every other day during the third month, with subsequent doses adjusted as clinically indicated. The dose of colchicine was 0.6-1.2 mg/d, as tolerated. The presence of a rim of subpleural honeycomb change was present in all of the 25 subjects who had HRCT. Subjects treated with high-dose prednisone alone experienced a higher incidence of serious side effects and also exhibited a trend (not statistically significant, p = 0.391) to more rapid decline of pulmonary function and shortened survival than did those treated with colchicine alone. In most subjects with typical clinical and HRCT features of idiopathic UIP, neither prednisone nor colchicine resulted in objective improvement, and the disease continued to progress in the majority. Colchicine appears to be a safer alternative to a trial of high-dose prednisone but may be no different than no therapy.

Accuracy of high-resolution CT in diagnosing lung diseases.

OBJECTIVE: The purpose of our study was to determine if high-resolution CT facilitates the diagnoses of three diseases that cause cystic air spaces in the lungs: pulmonary eosinophilic granuloma, pulmonary lymphangiomyomatosis, and emphysema. MATERIALS AND METHODS: Retrospective review of high-resolution CT findings in patients with pathologically proven pulmonary eosinophilic granuloma (n = 10), pulmonary lymphangiomyomatosis (n = 9), and emphysema (n = 10) and five control patients without cystic air spaces was conducted by two thoracic radiologists unaware of the pathologic diagnosis. After reviewing the scans, the radiologists made a diagnosis and indicated their level of confidence in the diagnosis on a three-point scale. RESULTS: High-resolution CT allowed the two radiologists to be confident of the diagnosis of pulmonary eosinophilic granuloma in 84% of CT scans, lymphangiomyomatosis in 79%, and emphysema in 95%. When confident, the observers were correct in 100% of the cases. Agreement between observers was good for confident diagnoses based on high-resolution CT scans of pulmonary eosinophilic granuloma (kappa = .77), lymphangiomyomatosis (kappa = .88), and emphysema (kappa = 1). Distribution of cystic changes differed on high-resolution CT scans for lymphangiomyomatosis and pulmonary eosinophilic granuloma. No consistent distribution pattern was observed for emphysema. Lack of a perceptible cyst wall was unique to cases of emphysema. All patients with lymphangiomyomatosis lacked nodules in the intervening lung parenchyma, whereas most patients with pulmonary eosinophilic granuloma had parenchymal nodules. CONCLUSION: High-resolution CT can help radiologists reliably diagnose pulmonary eosinophilic granuloma, lymphangiomyomatosis, and emphysema.

Technical aspects of twin screen-film chest radiography: cost effective lung and mediastinal imaging.

OBJECTIVE: To determine the sensitometry and 'cross-talk' of a twin screen-film cassette and to assess its clinical potential. MATERIALS AND METHODS: The twin cassette utilises two sets of screens, divided by filter material, to provide an optimised image of the mediastinum and the lungs. The exposure difference for the two images was measured sensitometrically. The contribution to film density of visible light and K-characteristic radiation, from adjacent screens in the absence of a dividing filter, was investigated. RESULT: Clinical experience indicated that an exposure difference of 3.4 between the front and back screens, was optimal. Visible light and K-characteristic radiation from the front screens, contributed up to 20 and 24% respectively, of the back film exposure and screen absorbed energy respectively. This was reduced to 0 and 6% with the use of the filter. CONCLUSIONS: The twin screen-film cassette provides extended latitude to enable optimal visualisation of the lung and mediastinal regions. Adjacent screen 'cross-talk' has been overcome to allow standard and portable chest applications.

Clinical evaluation of twin screen-film chest radiography: cost effective lung and mediastinal imaging.

OBJECTIVE: A new twin screen-film cassette system optimised for conventional chest radiography was evaluated by four thoracic radiologists. MATERIALS AND METHODS: The twin screen-film cassette system produces two film images, the front film optimised for the mediastinal region of the chest, the rear for the lung region. Image degradation on either screen-film system due to internal photon scatter has been virtually eliminated due to the use of a dividing filter. Fifty patients were included in a trial that resulted in a set of chest images for each patient, taken on the same inspiration, by both the twin screen-film cassette and the conventional system. The resultant fifty sets of images were evaluated by four chest radiologists who scored 12 radiographic features of the chest and patient pathologies present, using a paired difference technique. RESULTS: The image quality of the twin screen-film cassette system was judged to be significantly superior to the conventional screen-film system in nine of the 12 radiographic features scored (P < 0.003). In the three other regions and for the patient pathologies, no significant conclusions were drawn. CONCLUSION: The new twin screen-film system showed improved visualisation of radiographic features, particularly in the mediastinal and retrocardiac lung regions. This new system shows promise in both standard and portable clinical applications.

Late-onset noninfectious pulmonary complications after allogeneic bone marrow transplantation.

We examined the incidence and clinical outcome of late-onset noninfectious pulmonary complications (LONIPC) in a series of 234 patients who underwent allogeneic bone marrow transplantation at our institution between April 1982 and October 1996. The 179 patients who survived 3 months or more were evaluated. Clinical, radiologic, pulmonary function, and pathologic tests were reviewed to identify 18 patients (10%) who fulfilled the diagnostic criteria of LONIPC. Accordingly, the pulmonary processes included bronchiolitis obliterans (BO, five patients), bronchiolitis obliterans with organizing pneumonia (BOOP, three patients), diffuse alveolar damage (DAD, one patient), lymphocytic interstitial pneumonia (LIP, one patient), and nonclassifiable interstitial pneumonia (NCIP, eight patients). Various methods of enhanced immunosuppressive therapy resulted in marked durable remission in nine patients (50%) (3/3 with BOOP, 3/8 with NCIP, 1/1 with DAD, 1/1 with LIP, 1/5 with BO). The presence of chronic graft-versus-host disease (cGVHD) and prophylaxis for GVHD with cyclosporine and prednisone were the only variables significantly associated with the development of LONIPC (P = 0.0001 and 0.008, respectively). Regardless of histology, a reduction in the forced expiratory volume to < 45% of the predicted range was associated with poor response to treatment. These findings suggest a strong association between cGVHD and LONIPC and that the risk of LONIPC development may be influenced by the particular method of GVHD prophylaxis. Most patients with BOOP or mild airflow limitation at diagnosis achieved durable remissions.