The Thoracic Research Evaluation and Treatment 2.0 Model: A Lung Cancer Prediction Model for Indeterminate Nodules Referred for Specialist Evaluation.

BACKGROUND: Appropriate risk stratification of indeterminate pulmonary nodules (IPNs) is necessary to direct diagnostic evaluation. Currently available models were developed in populations with lower cancer prevalence than that seen in thoracic surgery and pulmonology clinics and usually do not allow for missing data. We updated and expanded the Thoracic Research Evaluation and Treatment (TREAT) model into a more generalized, robust approach for lung cancer prediction in patients referred for specialty evaluation. RESEARCH QUESTION: Can clinic-level differences in nodule evaluation be incorporated to improve lung cancer prediction accuracy in patients seeking immediate specialty evaluation compared with currently available models? STUDY DESIGN AND METHODS: Clinical and radiographic data on patients with IPNs from six sites (N = 1,401) were collected retrospectively and divided into groups by clinical setting: pulmonary nodule clinic (n = 374; cancer prevalence, 42%), outpatient thoracic surgery clinic (n = 553; cancer prevalence, 73%), or inpatient surgical resection (n = 474; cancer prevalence, 90%). A new prediction model was developed using a missing data-driven pattern submodel approach. Discrimination and calibration were estimated with cross-validation and were compared with the original TREAT, Mayo Clinic, Herder, and Brock models. Reclassification was assessed with bias-corrected clinical net reclassification index and reclassification plots. RESULTS: Two-thirds of patients had missing data; nodule growth and fluorodeoxyglucose-PET scan avidity were missing most frequently. The TREAT version 2.0 mean area under the receiver operating characteristic curve across missingness patterns was 0.85 compared with that of the original TREAT (0.80), Herder (0.73), Mayo Clinic (0.72), and Brock (0.68) models with improved calibration. The bias-corrected clinical net reclassification index was 0.23. INTERPRETATION: The TREAT 2.0 model is more accurate and better calibrated for predicting lung cancer in high-risk IPNs than the Mayo, Herder, or Brock models. Nodule calculators such as TREAT 2.0 that account for varied lung cancer prevalence and that consider missing data may provide more accurate risk stratification for patients seeking evaluation at specialty nodule evaluation clinics.

Emotional Distress, Anxiety, and General Health Status in Patients With Newly Identified Small Pulmonary Nodules: Results From the Watch the Spot Trial.

BACKGROUND: Anxiety and emotional distress have not been studied in large, diverse samples of patients with pulmonary nodules. RESEARCH QUESTION: How common are anxiety and distress in patients with newly identified pulmonary nodules, and what factors are associated with these outcomes? STUDY DESIGN AND METHODS: This study surveyed participants in the Watch the Spot Trial, a large, pragmatic clinical trial of more vs less intensive strategies for radiographic surveillance of patients with small pulmonary nodules. The survey included validated instruments to measure patient-centered outcomes such as nodule-related emotional distress (Impact of Event Scale-Revised) and anxiety (Six-Item State Anxiety Inventory) 6 to 8 weeks following nodule identification. Mixed-effects models were used to compare outcomes between study arms following adjustment for potential confounders and clustering within enrollment site, while also examining a limited number of prespecified explanatory factors, including nodule size, mode of detection, type of ordering clinician, and lack of timely notification prior to contact by the study team. RESULTS: The trial enrolled 34,699 patients; 2,049 individuals completed the baseline survey (5.9%). Respondents and nonrespondents had similar demographic and nodule characteristics, although more respondents were non-Hispanic and White. Impact of Event Scale-Revised scores indicated mild, moderate, or severe distress in 32.2%, 9.4%, and 7.2% of respondents, respectively, with no difference in scores between study arms. Following adjustment, greater emotional distress was associated with larger nodule size and lack of timely notification by a clinician; distress was also associated with younger age, female sex, ever smoking, Black race, and Hispanic ethnicity. Anxiety was associated with lack of timely notification, ever smoking, and female sex. INTERPRETATION: Almost one-half of respondents experienced emotional distress 6 to 8 weeks following pulmonary nodule identification. Strategies are needed to mitigate the burden of distress, especially in younger, female, ever smoking, and minoritized patients, and those with larger nodules. CLINICAL TRIAL REGISTRATION: ClinicalTrials.gov; No.: NCT02623712; URL: www. CLINICALTRIALS: gov.

Derivation and validation of a prediction model for histopathologic fibrotic hypersensitivity pneumonitis.

BACKGROUND: Clinical differentiation of fibrotic hypersensitivity pneumonitis (f-HP) remains challenging given variable and overlapping presentations with other fibrotic interstitial lung disease (f-ILD). OBJECTIVE: We derived a multivariable model for predicting histopathologic f-HP to better inform multidisciplinary team discussion (MDD) diagnosis, particularly when biopsy may be unsafe or cannot be achieved. METHODS: Patients with histopathologically-defined f-HP and other overlapping f-ILD were reviewed for distinguishing clinical and radiological variables. Using elastic net logistic regression, a penalized regression approach to minimize overfitting, a clinical model built on non-invasive assessments was derived for the prediction of histopathologic f-HP. This model was then validated in an independently derived external cohort from three sites. RESULTS: The derivation and validation cohorts consisted of 248 (84 cHP and 164 other f-ILD) and 157 (82 f-HP and 75 other f-ILD) histopathologically-defined patients, respectively (total study N = 405). Variables retained from the elastic net model included age in years (regression coefficient 0.033), male sex (-1.109), positive exposure history (1.318), percent predicted forced vital capacity (-0.021), radiologic peribronchovascular axial ILD distribution (0.199), mid (-0.22) or lower lobe (-0.839) craniocaudal or patchy (0.287) ILD distribution, upper (1.188) or equivalent upper and lower lobe (0.237) traction bronchiectasis, mosaic attenuation (1.164), and centrilobular nodules (2.045). Bias corrected AUC was 0.84 (standard error = 0.02) for the derivation cohort and 0.80 (CI 0.73-0.87) for the validation cohort. CONCLUSIONS: This multivariable model demonstrated good predictive performance for delineating histopathologically-defined f-HP from other f-ILD as a means of avoiding or justifying biopsy and supporting MDD diagnostic confidence.

Methods for the Watch the Spot Trial. A Pragmatic Trial of More- versus Less-Intensive Strategies for Active Surveillance of Small Pulmonary Nodules.

Small pulmonary nodules are most often managed by surveillance imaging with computed tomography (CT) of the chest, but the optimal frequency and duration of surveillance are unknown. The Watch the Spot Trial is a multicenter, pragmatic, comparative-effectiveness trial with cluster randomization by hospital or health system that compares more- versus less-intensive strategies for active surveillance of small pulmonary nodules. The study plans to enroll approximately 35,200 patients with a small pulmonary nodule that is newly detected on chest CT imaging, either incidentally or by screening. Study protocols for more- and less-intensive surveillance were adapted from published guidelines. The primary outcome is the percentage of cancerous nodules that progress beyond American Joint Committee on Cancer seventh edition stage T1a. Secondary outcomes include patient-reported anxiety and emotional distress, nodule-related health care use, radiation exposure, and adherence with the assigned surveillance protocol. Distinctive aspects of the trial include: 1) the pragmatic integration of study procedures into existing clinical workflow; 2) the use of cluster randomization by hospital or health system; 3) the implementation and evaluation of a system-level intervention for protocol-based care; 4) the use of highly efficient, technology-enabled methods to identify and (passively) enroll participants; 5) reliance on data collected as part of routine clinical care, including data from electronic health records and state cancer registries; 6) linkage with state cancer registries for complete ascertainment of the primary study outcome; and 7) intensive engagement with a diverse group of patient and nonpatient stakeholders in the design and execution of the study.

Diagnostic utility of surgical lung biopsies in elderly patients with indeterminate interstitial lung disease.

BACKGROUND AND OBJECTIVE: Idiopathic pulmonary fibrosis (IPF) is increasingly diagnosed by clinical and computed tomography (CT) criteria; however, surgical lung biopsy (SLB) may still be required in patients who lack definite CT features of usual interstitial pneumonia (UIP). We reviewed a cohort of elderly patients who underwent SLB, to evaluate the benefit of SLB in diagnosing idiopathic interstitial pneumonia (IIP). METHODS: We searched the pathology records of Mayo Clinic for ambulatory patients at least 75 years old, who underwent SLB between 2000 and 2012 for indeterminate IIP. Histologic slides were reviewed and clinical data were extracted from the record. RESULTS: A total of 55 patients (35 male) were enrolled. Median (interquartile range) age was 77 (76-80) years. Forced vital capacity was 70 (61-76)% and diffusing capacity of the lungs for carbon monoxide was 48 (42-54)% of predicted. In total, 37 (67%) patients had IPF, including 61% of those with HRCT findings inconsistent with UIP. Thirty-day mortality was 10% and 90-day mortality was 15%. CONCLUSION: The high mortality rate of SLB complicates the risk-benefit analysis in elderly patients with IIP. The expected value of the SLB is probably highest when the HRCT features are inconsistent with UIP, due to the frequent (39%) retrieval of patterns other than UIP.

Assessment of Fluorodeoxyglucose F18-Labeled Positron Emission Tomography for Diagnosis of High-Risk Lung Nodules.

Importance: Clinicians rely heavily on fluorodeoxyglucose F18-labeled positron emission tomography (FDG-PET) imaging to evaluate lung nodules suspicious for cancer. We evaluated the performance of FDG-PET for the diagnosis of malignancy in differing populations with varying cancer prevalence. Objective: To determine the performance of FDG-PET/computed tomography (CT) in diagnosing lung malignancy across different populations with varying cancer prevalence. Design, Setting, and Participants: Multicenter retrospective cohort study at 6 academic medical centers and 1 Veterans Affairs facility that comprised a total of 1188 patients with known or suspected lung cancer from 7 different cohorts from 2005 to 2015. Exposures: 18F fluorodeoxyglucose PET/CT imaging. Main Outcome and Measures: Final diagnosis of cancer or benign disease was determined by pathological tissue diagnosis or at least 18 months of stable radiographic follow-up. Results: Most patients were male smokers older than 60 years. Overall cancer prevalence was 81% (range by cohort, 50%-95%). The median nodule size was 22 mm (interquartile range, 15-33 mm). Positron emission tomography/CT sensitivity and specificity were 90.1% (95% CI, 88.1%-91.9%) and 39.8% (95% CI, 33.4%-46.5%), respectively. False-positive PET scans occurred in 136 of 1188 patients. Positive predictive value and negative predictive value were 86.4% (95% CI, 84.2%-88.5%) and 48.7% (95% CI, 41.3%-56.1%), respectively. On logistic regression, larger nodule size and higher population cancer prevalence were both significantly associated with PET accuracy (odds ratio, 1.027; 95% CI, 1.015-1.040 and odds ratio, 1.030; 95% CI, 1.021-1.040, respectively). As the Mayo Clinic model-predicted probability of cancer increased, the sensitivity and positive predictive value of PET/CT imaging increased, whereas the specificity and negative predictive value dropped. Conclusions and Relevance: High false-positive rates were observed across a range of cancer prevalence. Normal PET/CT scans were not found to be reliable indicators of the absence of disease in patients with a high probability of lung cancer. In this population, aggressive tissue acquisition should be prioritized using a comprehensive lung nodule program that emphasizes advanced tissue acquisition techniques such as CT-guided fine-needle aspiration, navigational bronchoscopy, and endobronchial ultrasonography.

A Case of Simultaneous Benign Metastasizing Leiomyomas and Disseminated Peritoneal Leiomyomatosis Following Endoscopic Power Morcellation for Uterine Disease.

Extrauterine spread of leiomyomas is rare and most commonly occurs in the lungs. We present a case of simultaneous metastatic leiomyomatosis to the lungs and peritoneal cavity following laparoscopic myomectomy with power morcellation. The patient presented to our institution for further management where she underwent a robotically assisted hysterectomy with bilateral salpingo-oophorectomy. Leiomyomatous implants measuring up to 2.4 cm were resected from bowel mesentery and bladder peritoneum. Subsequent serial computed tomography imaging confirmed stable pulmonary nodules without new intraperitoneal lesions. Increasing number of cases involving extrauterine spread of leiomyomas has been reported with the introduction of power morcellation. The exact pathogenesis is unknown but is likely multifactorial. We emphasize that although the incidence of spread of benign disease is low, it is important to recognize this phenomenon as we will likely continue to encounter similar cases in the coming years.

Coexistent pulmonary granulomatosis with polyangiitis (Wegener granulomatosis) and Crohn disease.

Crohn disease (CD) may be associated with various extraintestinal manifestations, including, rarely, respiratory tract involvement. When necrobiotic pulmonary nodules are present, the differential diagnosis includes granulomatosis with polyangiitis (Wegener granulomatosis) (GPA). The respiratory tract manifestations of CD and GPA may mimic each other, complicating the diagnosis and suggesting the possible coexistence of these 2 conditions. The aim of this study was to describe the clinical, radiographic, and pathologic features of patients in whom CD and GPA coexist. We reviewed the teaching files of the authors and searched the Mayo Clinic medical records for coexistent inflammatory bowel diseases and antineutrophilic cytoplasmic antibodies (ANCA)-associated vasculitides. We reviewed in detail 97 patient charts and excluded cases of ulcerative colitis and those in whom only one of the diagnoses was present. Pulmonary and gastrointestinal biopsies were reviewed when available. We also searched the medical literature for previously published cases. We found 6 cases of coexistent CD and pulmonary GPA and 4 cases with extrapulmonary GPA; 3 cases (all with extrapulmonary GPA) have been published previously. The diagnosis of CD preceded that of GPA in 11 cases. Proteinase 3-ANCA was positive in 6 cases, negative in 2, and not reported in 5 cases. Myeloperoxidase-ANCA was negative in 6 cases and unavailable in the remainder of patients. Pathology revealed features diagnostic of GPA in all cases with necrotizing granulomatous inflammation and segmental vasculitis. Pulmonary findings in patients with CD or the presence of granulomatous colitis in patients with GPA should prompt the inclusion in the differential diagnosis of a possible coexistence of CD and GPA.

Lymphoid hyperplasia and eosinophilic pneumonia as histologic manifestations of amiodarone-induced lung toxicity.

Amiodarone use is often limited by pulmonary toxicity. Amiodarone lung disease (ALD) classically manifests as organizing pneumonia with intra-alveolar foamy macrophages, but other patterns may also occur. Here we report 2 previously unreported patterns of ALD: lymphoid hyperplasia (LH) and eosinophilic pneumonia (EP). We identified patients with LH or EP as a prominent feature among 75 cases of probable ALD from the authors' teaching files collected from 1997 to 2010. Clinical history and lung wedge biopsies were reviewed. Twelve patients (7 men) met inclusion criteria (median age, 71 y). The exact amiodarone dose was known in all cases (median, 200 mg/d). Treatment duration was known in 10 cases and ranged from 1 to 12 years. Thoracic imaging showed diffuse infiltrates causing concern for a diagnosis of ALD. Histologic review revealed intra-alveolar foamy macrophages in all cases. Eight cases prominently displayed patterns of LH, including diffuse LH (7), follicular bronchiolitis (5), lymphoid interstitial pneumonia (2), and lymphocytic perivascular cuffing (2). Two showed features of acute EP, including diffuse alveolar damage with abundant eosinophils. Two showed features of chronic EP, including interstitial pneumonia with abundant eosinophils, patchy organization, and fibrinous exudates with macrophages and eosinophils. One chronic EP case also showed focal LH. Additional features included intra-alveolar giant cells (6), pleuritis (3), small poorly formed granulomas (3), and thrombi (2). LH and EP are previously unrecognized histopathologic manifestations of ALD, and amiodarone exposure should be included in their differential diagnosis.

Causes of pulmonary granulomas: a retrospective study of 500 cases from seven countries.

BACKGROUND: The frequencies of various causes of pulmonary granulomas in pathological material are unknown, as is the influence of geographical location on aetiology. The aim of this study was to identify the causes of pulmonary granulomas in pathological specimens, to define their frequencies, and to determine whether these causes vary by geographical location. METHODS: 500 lung biopsies and resections containing granulomas were reviewed retrospectively by expert pulmonary pathologists from 10 institutions in seven countries. Fifty consecutive cases from each location were assigned a diagnosis based on histological features and available clinical/microbiological data. RESULTS: A specific cause was identified in 58% of cases (290/500), most commonly sarcoidosis (136, 27%) and mycobacterial or fungal infections (125, 25%). Mycobacteria were identified in 19% of cases outside the USA versus 8% within the USA. In contrast, fungi accounted for 19% cases in the USA versus 4% in other locations. Fungi were mostly detected by histology, whereas most mycobacteria were identified in cultures. In 42% of cases (210/500) an aetiology could not be determined. CONCLUSIONS: Across several geographical settings, sarcoidosis and infections are the most common causes of pulmonary granulomas diagnosed in pathological specimens. Fungi are more commonly identified than mycobacteria in the USA, whereas the reverse is true in other countries. A definite aetiology cannot be demonstrated in more than a third of all cases of pulmonary granulomas, even after histological examination. These findings highlight the need to submit material for histology as well as cultures in all cases in which granulomatous disease enters the differential diagnosis.

Pleuropulmonary infection by Paragonimus westermani in the United States: a rare cause of Eosinophilic pneumonia after ingestion of live crabs.

Infections caused by the parasite Paragonimus westermani are endemic to Southeast Asia. Most infections reported in the United States are among immigrants who acquired the disease abroad. Due to the nonspecific nature of its presentation and rarity in the United States, the diagnosis may first be suggested by the pathologist on biopsy review. Definitive diagnosis may need serologic testing for confirmation. We report 4 cases of pleuropulmonary disease caused by United States-acquired P. westermani, which were identified in the consultation files of the authors. Patients (3 men and 1 woman; aged, 20 to 66 y) presented with pulmonary complaints and chest imaging abnormalities including cavitary infiltrates (2), lung mass (1), pleural effusion (1), and pneumothorax (1). Biopsies showed chronic eosinophilic pneumonia and organizing pneumonia in all cases. Other pathologic findings included granulomatous inflammation with geographic necrosis (3), vasculitis (3), and pleuritis (3). Paragonimus organisms and/or eggs were identified in 2 cases. Serologic studies were positive for P. westermani in 3 cases (2 enzyme-linked immunosorbent assay and 1 immunoblot). Three patients ate live crabs at sushi bars (including crabs in martinis, a previously unreported mechanism for infection). In 1 patient, the source of infection was uncertain. Paragonimiasis should be considered in the differential diagnosis of patients with eosinophilic pleuropulmonary disease in the United States. Although eosinophilic pneumonia was a consistent finding, the biopsies may be nonspecific as the organisms and/or eggs are not always visualized. Unusual features include marked pleuritis, foci of geographic necrosis and granulomatous vasculitis. A history of ingestion and targeted serologies are the keys to diagnosis.

Surgery for pulmonary coccidioidomycosis: a 10-year experience.

BACKGROUND: Coccidioidomycosis results from infection with Coccidioides species endemic to the southwestern United States. The mobile US population has resulted in incremental cases being found throughout the world. The fungal infection can result in pulmonary sequelae, including nodules, cavities, and complications requiring treatment by the thoracic surgeon. METHODS: A retrospective chart review was conducted of 1,496 patients with coccidioidomycosis treated at our institution (January 1998 to December 2008) to identify those requiring surgery. RESULTS: Of the 1,496 patients, 86 (6%; mean age, 58 years [range, 18 to 81], 48 women) underwent operations. Radiographs revealed 59 nodules, 18 cavities, 2 infiltrates, and 7 complications of disease (e.g., effusion, pneumothorax, and empyema). Of the 86 patients, 40% underwent resection for persistent symptoms or disease progression despite adequate antifungal therapy. One third of the operations were performed by video-assisted thoracoscopic surgery. Morbidity, 21% (18 patients), and in-hospital mortality, 2% (2 patients), were greater after resection for cavitary lesions with resultant complications versus for nodular disease: 41% versus 12% (p < or = 0.002) and 8% versus 0% (p < 0.005). Prolonged air leaks or bronchopleural fistulas were the most common complications (13 patients). Postoperative antifungal therapy was administered to 42% of patients (89% of cavitary and complicated). There were no cases of recurrence at follow-up (mean, 24 months). CONCLUSIONS: Surgical intervention was indicated for only a few patients, most commonly for diagnostic dilemmas involving nodular disease, symptomatic nonresponsive cavitary disease, or complications. Prolonged air leaks were the main cause of morbidity. Resection should result in symptom resolution and long-term freedom from recurrence.

Pneumonia and osteomyelitis due to Legionella longbeachae in a woman with systemic lupus erythematosus.

A patient with risk factors of systemic lupus erythematosus, corticosteroid use, and malignancy received a diagnosis of concomitant pneumonia and osteomyelitis caused by Legionella longbeachae. In this report, the first description of Legionella osteomyelitis, previous cases of extrapulmonary Legionella infection are detailed.

Longitudinal transcriptional analysis of developing neointimal vascular occlusion and pulmonary hypertension in rats.

Pneumonectomized rats injected with the alkaloid toxin, monocrotaline, develop progressive neointimal pulmonary vascular obliteration and pulmonary hypertension resulting in right ventricular failure and death. The antiproliferative immunosuppressant, triptolide, attenuates neointimal formation and pulmonary hypertension in this disease model (Faul JL, Nishimura T, Berry GJ, Benson GV, Pearl RG, and Kao PN. Am J Respir Crit Care Med 162: 2252-2258, 2000). Pneumonectomized rats, injected with monocrotaline on day 7, were killed at days 14, 21, 28, and 35 for measurements of physiology and gene expression patterns. These data were compared with pneumonectomized, monocrotaline-injected animals that received triptolide from day 5 to day 35. The hypothesis was tested that a group of functionally related genes would be significantly coexpressed during the development of disease and downregulated in response to treatment. Transcriptional analysis using total lung RNA was performed on replicate animals for each experimental time point with exploratory data analysis followed by statistical significance analysis. Marked, statistically significant increases in proteases (particularly derived from mast cells) were noted that parallel the development of vascular obliteration and pulmonary hypertension. Mast-cell-derived proteases may play a role in regulating the development of neointimal pulmonary vascular occlusion and pulmonary hypertension in response to injury.

Simvastatin rescues rats from fatal pulmonary hypertension by inducing apoptosis of neointimal smooth muscle cells.

BACKGROUND: Pulmonary vascular injury by toxins can induce neointimal formation, pulmonary arterial hypertension (PAH), right ventricular failure, and death. We showed previously that simvastatin attenuates smooth muscle neointimal proliferation and pulmonary hypertension in pneumonectomized rats injected with the alkaloid toxin monocrotaline. The present study was undertaken to investigate the efficacy of simvastatin and its mechanism of reversing established neointimal vascular occlusion and pulmonary hypertension. METHODS AND RESULTS: Pneumonectomized rats injected with monocrotaline at 4 weeks demonstrated severe PAH at 11 weeks (mean pulmonary artery pressure [mPAP]=42 versus 17 mm Hg in normal rats) and death by 15 weeks. When rats with severe PAH received simvastatin (2 mg x kg(-1) x d(-1) by gavage) from week 11, there was 100% survival and reversal of PAH after 2 weeks (mPAP=36 mm Hg) and 6 weeks (mPAP=24 mm Hg) of therapy. Simvastatin treatment reduced right ventricular hypertrophy and reduced proliferation and increased apoptosis of pathological smooth muscle cells in the neointima and medial walls of pulmonary arteries. Longitudinal transcriptional profiling revealed that simvastatin downregulated the inflammatory genes fos, jun, and tumor necrosis factor-alpha and upregulated the cell cycle inhibitor p27Kip1, endothelial nitric oxide synthase, and bone morphogenetic protein receptor type 1a. CONCLUSIONS: Simvastatin reverses pulmonary arterial neointimal formation and PAH after toxic injury.

Simvastatin attenuates smooth muscle neointimal proliferation and pulmonary hypertension in rats.

Hypertensive pulmonary vascular disease is characterized by abnormal proliferation of vascular endothelial and smooth muscle cells, leading to occlusion of pulmonary arterioles, pulmonary hypertension, right ventricular failure, and death. Compounds with antiproliferative effects on vascular endothelial and smooth muscle cells, such as 3-hydroxy-3-methylglutaryl-coenzyme A (HMG-CoA) reductase inhibitors, may prevent the development of experimental hypertensive pulmonary vascular disease. Pneumonectomized rats injected with monocrotaline at 7 days develop severe hypertensive pulmonary vascular disease with neointimal formation. Rats were randomized to receive either vehicle or treatment with the HMG-CoA reductase inhibitor simvastatin (2 mg/kg per day). By Day 35, rats that received vehicle had higher mean pulmonary arterial pressures (53 +/- 2 mm Hg) and right ventricular hypertrophy (right ventricle/[left ventricle plus septum] [RV/LV+S] = 0.78 +/- 0.09) than rats in Group PMS5-35 that received simvastatin from Day 5 to 35 (mean pulmonary arterial pressure = 27 +/- 3 mm Hg, RV/LV+S = 0.34 +/- 0.08; p < or = 0.001). Pulmonary vascular remodeling with neointimal formation consisting of vascular smooth muscle cells was more severe in vehicle-treated rats (vascular occlusion score, 1.98 +/- 0.02) than in Group PMS5-35 (vascular occlusion score, 0.59 +/- 0.46; p < 0.001). In addition, lung endothelial nitric oxide synthase gene expression was decreased in vehicle-treated animals but was restored toward normal levels in simvastatin-treated animals. Simvastatin attenuates monocrotaline-induced pulmonary vascular remodeling with neointimal formation, pulmonary arterial hypertension, and right ventricular hypertrophy in rats.

Achieving tobacco cessation: current status, current problems, future possibilities.

Assisting smokers to achieve tobacco cessation has always been difficult. The development of pharmacological approaches to the attainment of abstinence from tobacco usage has been very helpful, although our understanding of optimal clinical use is still incomplete and imperfect. Bupropion and nicotine therapy (NT) will help reduce the severity of nicotine withdrawal symptoms, whether used separately or in combination. Effectiveness is greater with the combination of drugs than with either drug alone. Nevertheless, the initial 'quit rate' is usually less than 50%, and there is a considerable decrease in the abstinence rate after the course of therapy has been completed. Effectiveness is increased if higher doses of NT are employed, with or without concomitant bupropion. Much remains to be learned about optimal doses, preferred durations of therapy and tapering, prevention and management of relapses, and selection of modes of delivery of NT. The discovery that nicotine dependence has a major genetic component has stimulated much interest and many research studies. The preliminary results are interesting, to say the least.