Leukemic pulmonary infiltrates in chronic lymphocytic leukemia: Clinical and imaging features.

BACKGROUND: Chronic lymphocytic leukemia (CLL) is the most common type of leukemia in Western countries. Although various patterns of lung involvement with CLL have been reported, data on clinicoradiologic presentation are sparse. METHODS: A computer-assisted search was conducted to identify patients encountered at Mayo Clinic from 1998 to 2022 and had leukemic pulmonary infiltrates (LPI) with CLL demonstrated on lung biopsy. Medical records and chest imaging studies were reviewed to identify clinical and radiologic features. RESULTS: Among 13 patients, median age was 77 years (range: 60-88) and included 10 men (77 %). All patients were known to have CLL with a median duration of 96 months (range: 50-408), and none were on treatment. Most common symptoms were dyspnea (62 %), cough (54 %), and fatigue (46 %); 2 patients (15 %) were asymptomatic. Dominant abnormality on CT consisted of single or multiple nodular/mass-like opacities in 10 patients (77 %), while diffuse centrilobular nodules, pleural mass, and diffuse bronchial wall thickening were each seen in one patient, respectively; intrathoracic lymphadenopathy was present in all. After diagnosis of LPI, treatment for CLL was administered to 7 patients (54 %); 6 patients (86 %) exhibited improvement. During follow-up (median 41 months), 8 (62 %) patients died. Causes of death included progressive CLL or treatment-related complications (2 patients), pneumonia (1 patient), unrelated causes (3 patients), and unknown in 2 patients. CONCLUSIONS: LPI in CLL is generally encountered in patients with known untreated CLL. The main imaging feature is single mass-like opacity or multiple nodular/mass-like opacities, associated with intrathoracic lymphadenopathy.

Clinical Outcomes With and Without Plasma Exchange in the Treatment of Rapidly Progressive Interstitial Lung Disease Associated With Idiopathic Inflammatory Myopathy.

BACKGROUND/OBJECTIVE: A subset of patients with idiopathic inflammatory myopathy (IIM) develops highly fatal, rapidly progressive interstitial lung disease (RP-ILD). Treatment strategies consist of glucocorticoid and adjunctive immunosuppressive therapies. Plasma exchange (PE) is an alternative therapy, but its benefit is unclear. In this study, we aimed to determine whether PE benefited outcomes for patients with RP-ILD. METHODS: In this medical records review study, we compared baseline characteristics and clinical outcomes for 2 groups of patients with IIM-related RP-ILD: those who received and did not receive PE. RESULTS: Our cohort consisted of 15 patients, 9 of whom received PE. Baseline demographic characteristics and severity of lung, skin, and musculoskeletal disease between the 2 groups of patients were not significantly different. Five patients required mechanical ventilation (2, PE; 3, no PE). Plasma exchange was generally a third-line adjunctive treatment option. The PE group had a longer median (interquartile range) hospitalization (27.0 [23.0-36.0] days) than the non-PE group (12.0 [8.0-14.0] days) ( p = 0.02). There was a potential benefit in 30-day mortality improvement in those receiving PE (0% vs 33%, p = 0.14), with a statistically significant improvement in 2 important composite end points including 30-day mortality or need for lung transplant (0% vs 50%, p = 0.04) and 1-year mortality or need for lung transplant or hospital readmission for RP-ILD in those receiving PE (22% vs 83%, p = 0.04). CONCLUSIONS: Plasma exchange may be an underutilized, safe salvage therapy for patients with IIM-related RP-ILD when other immunosuppressive therapies fail.

Lung Cancer Screening Using Clinical Photon-Counting Detector Computed Tomography and Energy-Integrating-Detector Computed Tomography: A Prospective Patient Study.

OBJECTIVE: To evaluate the diagnostic quality of photon-counting detector (PCD) computed tomography (CT) in patients undergoing lung cancer screening compared with conventional energy-integrating detector (EID) CT in a prospective multireader study. MATERIALS: Patients undergoing lung cancer screening with conventional EID-CT were prospectively enrolled and scanned on a PCD-CT system using similar automatic exposure control settings and reconstruction kernels. Three thoracic radiologists blinded to CT system compared PCD-CT and EID-CT images and scored examinations using a 5-point Likert comparison score (-2 [left image is worse] to +2 [left image is better]) for artifacts, sharpness, image noise, diagnostic image quality, emphysema visualization, and lung nodule evaluation focusing on the border. Post hoc correction of Likert scores was performed such that they reflected PCD-CT performance in comparison to EID-CT. A nonreader radiologist measured objective image noise. RESULTS: Thirty-three patients (mean, 66.9 ± 5.6 years; 11 female; body mass index; 30.1 ± 5.1 kg/m 2 ) were enrolled. Mean volume CT dose index for PCD-CT was lower (0.61 ± 0.21 vs 0.73 ± 0.22; P < 0.001). Pooled reader results showed significant differences between imaging modalities for all comparative rankings ( P < 0.001), with PCD-CT favored for sharpness, image noise, image quality, and emphysema visualization and lung nodule border, but not artifacts. Photon-counting detector CT had significantly lower image noise (74.4 ± 10.5 HU vs 80.1 ± 8.6 HU; P = 0.048). CONCLUSIONS: Photon-counting detector CT with similar acquisition and reconstruction settings demonstrated improved image quality and less noise despite lower radiation dose, with improved ability to depict pulmonary emphysema and lung nodule borders compared with EID-CT at low-dose lung cancer CT screening.

Estimating the Clinical Impact of Photon-Counting-Detector CT in Diagnosing Usual Interstitial Pneumonia.

OBJECTIVE: The aim of this study was to evaluate the clinical impact of a higher spatial resolution, full field-of-view investigational photon-counting detector computed tomography (PCD-CT) on radiologist confidence in imaging findings and diagnosis of usual interstitial pneumonia (UIP) compared with conventional energy-integrating detector CT (EID-CT). MATERIALS AND METHODS: Patients suspected of interstitial lung disease were scanned on a PCD-CT system after informed consent and a clinically indicated EID-CT. In 2 sessions, 3 thoracic radiologists blinded to clinical history and scanner type evaluated CT images of the right and left lungs separately on EID- or PCD-CT, reviewing each lung once/session, rating confidence in imaging findings of reticulation, traction bronchiectasis, honeycombing, ground-glass opacities (GGOs), mosaic pattern, and lower lobe predominance (100-point scale: 0-33, likely absent; 34-66, indeterminate; 67-100, likely present). Radiologists also rated confidence for the probability of UIP (0-20, normal; 21-40, inconsistent with UIP; 41-60, indeterminate UIP; 61-81; probable UIP; 81-100, definite UIP) and graded image quality. Because a confidence scale of 50 represented completely equivocal findings, magnitude score (the absolute value of confidence scores from 50) was used for analysis (higher scores were more confident). Image noise was measured for each modality. The magnitude score was compared using linear mixed effects regression. The consistency of findings and diagnosis between 2 scanners were evaluated using McNemar test and weighted κ statistics, respectively. RESULTS: A total of 30 patients (mean age, 68.8 ± 11.0 years; M:F = 18:12) underwent conventional EID-CT (median CTDI vol , 7.88 mGy) and research PCD-CT (median CTDI vol , 6.49 mGy). The magnitude scores in PCD-CT were significantly higher than EID-CT for imaging findings of reticulation (40.7 vs 38.3; P = 0.023), GGO (34.4 vs 31.7; P = 0.019), and mosaic pattern (38.6 vs 35.9; P = 0.013), but not for other imaging findings ( P ≥ 0.130) or confidence in UIP (34.1 vs 22.2; P < 0.059). Magnitude score of probability of UIP in PCD-CT was significantly higher than EID-CT in one reader (26.0 vs 21.5; P = 0.009). Photon-counting detector CT demonstrated a decreased number of indeterminate GGO (17 vs 26), an increased number of unlikely GGO (74 vs 50), and an increased number of likely reticulations (140 vs 130) relative to EID-CT. Interobserver agreements among 3 readers for imaging findings and probability of UIP were similar between PCD-CT and EID-CT (intraclass coefficient: 0.507-0.818 vs 0.601-0.848). Photon-counting detector CT had higher scores in overall image quality (4.84 ± 0.38) than those in EID-CT (4.02 ± 0.40; P < 0.001) despite increased image noise (mean 85.5 vs 36.1 HU). CONCLUSIONS: Photon-counting detector CT provided better image quality and improved the reader confidence for presence or absence of imaging findings of reticulation, GGO, and mosaic pattern with idiosyncratic improvement in confidence in UIP presence.

Clinical, radiologic, and pathologic features and outcomes of pulmonary transthyretin amyloidosis.

INTRODUCTION: Amyloid transthyretin amyloidosis (ATTR) is characterized by deposition of a misfolded conformation of the transport protein TTR, most commonly in cardiac and nerve tissue, causing clinical disease. Pulmonary amyloidosis, or deposition of ATTR in lung tissue, is a poorly characterized manifestation of this disease. We present the clinical course, imaging characteristics, pathology results, and outcomes of a patient cohort diagnosed with pulmonary ATTR. METHODS: We retrospectively reviewed records of 28 patients with pulmonary ATTR seen at Mayo Clinic from September 30, 2005, through December 31, 2020. Data collected included information on demographics, subjective symptoms, tissue biopsy results, pulmonary function testing, imaging findings, and treatment. RESULTS: Of the patients, 89% were men; the median age was 74.5 years (range, 50-99 years). Patients were typically diagnosed after persistent dyspnea and abnormal chest imaging resulted in lung biopsy, which yielded the ATTR diagnosis. Most patients had a preexisting diagnosis of cardiac ATTR. The disease was wild-type in 62% and hereditary in 38%. Normal pulmonary function tests followed by a restrictive pattern were the most common presentation. Of the patients, 93% had chest computed tomography, with common findings of diffuse nodularity, calcified granulomas, interlobular septal thickening, and pleural effusions. Almost all patients had pulmonary vascular involvement, and half had interstitial involvement on tissue biopsy. One-third received either anti-amyloid pharmacotherapy or a heart transplant. Half of patients had died before the time of study inclusion. CONCLUSION: Pulmonary disease is a less common but clinically important manifestation of ATTR.

Managing Incidental Findings on Thoracic CT: Lung Findings. A White Paper of the ACR Incidental Findings Committee.

The ACR Incidental Findings Committee presents recommendations for managing incidentally detected lung findings on thoracic CT. The Chest Subcommittee is composed of thoracic radiologists who endorsed and developed the provided guidance. These recommendations represent a combination of current published evidence and expert opinion and were finalized by informal iterative consensus. The recommendations address commonly encountered incidental findings in the lungs and are not intended to be a comprehensive review of all pulmonary incidental findings. The goal is to improve the quality of care by providing guidance on management of incidentally detected thoracic findings.

Pathology, Radiology, and Genetics of Interstitial Lung Disease in Patients With Shortened Telomeres.

Interstitial lung diseases (ILDs) in patients with shortened telomeres have not been well characterized. We describe demographic, radiologic, histopathologic, and molecular features, and p16 expression in patients with telomeres ≤10th percentile (shortened telomeres) and compare them to patients with telomere length >10th percentile. Lung explants, wedge biopsies, and autopsy specimens of patients with telomere testing were reviewed independently by 3 pathologists using defined parameters. High-resolution computed tomography scans were reviewed by 3 radiologists. p16-positive fibroblast foci were quantified. A multidisciplinary diagnosis was recorded. Patients with shortened telomeres (N=26) were morphologically diagnosed as usual interstitial pneumonia (UIP) (N=11, 42.3%), chronic hypersensitivity pneumonitis (N=6, 23.1%), pleuroparenchymal fibroelastosis, fibrotic nonspecific interstitial pneumonia, desquamative interstitial pneumonia (N=1, 3.8%, each), and fibrotic interstitial lung disease (fILD), not otherwise specified (N=6, 23.1%). Patients with telomeres >10th percentile (N=18) showed morphologic features of UIP (N=9, 50%), chronic hypersensitivity pneumonitis (N=3, 16.7%), fibrotic nonspecific interstitial pneumonia (N=2, 11.1%), or fILD, not otherwise specified (N=4, 22.2%). Patients with shortened telomeres had more p16-positive foci (P=0.04). The number of p16-positive foci correlated with outcome (P=0.0067). Thirty-nine percent of patients with shortened telomeres harbored telomere-related gene variants. Among 17 patients with shortened telomeres and high-resolution computed tomography features consistent with or probable UIP, 8 (47.1%) patients showed morphologic features compatible with UIP; multidisciplinary diagnosis most commonly was idiopathic pulmonary fibrosis (N=7, 41.2%) and familial pulmonary fibrosis (N=5, 29%) in these patients. In conclusion, patients with shortened telomeres have a spectrum of fILDs. They often demonstrate atypical and discordant features on pathology and radiology leading to diagnostic challenges.

Presenting Clinicoradiologic Features, Causes, and Clinical Course of Exogenous Lipoid Pneumonia in Adults.

BACKGROUND: Exogenous lipoid pneumonia (ELP) develops when lipid-containing substances enter the airways through aspiration or inhalation and incite an inflammatory response. The diagnosis of ELP often is difficult because findings may be nonspecific. The clinical course of ELP has not been well characterized. RESEARCH QUESTION: What are the presenting clinicoradiologic features of ELP, its causative agents, and clinical course? STUDY DESIGN AND METHODS: We searched the Mayo Clinic electronic medical records for patients diagnosed with ELP between 1998 and 2020. Inclusion diagnostic criteria were: (1) lipoid pneumonia (LP) on histopathologic examination, (2) lipid-laden macrophages in BAL fluid, or (3) fatty attenuation of parenchymal opacities on chest CT imaging. Additionally, all patients were required to have a clinician diagnosis of LP in the absence of conditions known to cause endogenous LP. RESULTS: Thirty-four patients were identified. Mean age was 71 years, with no sex predominance; one-half were asymptomatic. The diagnosis was confirmed by lung biopsy (including three lobectomies for suspected malignancy) in 71% of patients, CT scan in 24% of patients, and BAL in 5% of patients. Most patients manifested bilateral parenchymal opacities that commonly involved the lower lobes; fatty attenuation was identifiable in only 41% of patients. A causative substance was identified in 79% of patients, in most cases after the diagnosis was established. Over a median follow-up of 1.2 years, only 20% of patients with chronic respiratory symptoms improved, whereas 50% worsened. Over a median follow-up interval of 1 year, CT scan abnormalities improved or resolved in 33% of patients and progressed in 39% of patients. Patients who deteriorated were older, with a higher prevalence of GI disorders than those who remained stable or improved. INTERPRETATION: ELP often is asymptomatic and may not manifest fatty attenuation on chest CT imaging. Clinical and radiologic abnormalities persist or worsen in most affected patients, even when the causative agent is discontinued.

Pulmonary nodules in patients with primary Sjögren's syndrome: Causes, clinico-radiologic features, and outcomes.

BACKGROUND: Primary Sjögren's Syndrome (pSS) is characterized by an immune-mediated lymphoplasmacytic infiltration of the salivary and lacrimal glands. Pulmonary nodules are not uncommonly encountered in these patients. METHODS: We conducted a retrospective computer-assisted search for patients with pSS who were encountered at our institution between 1999 and 2018 and had histologically characterized pulmonary nodule(s)/mass (es) (PNs). RESULTS: Of 41 patients with pSS and PNs, median age was 67 years (IQR, 56-74), 94% were women, and 39% had a smoking history. The PNs proved to be non-Hodgkin lymphoma (NHL) in 16 patients (39%), lung carcinoma in 11 patients (27%), other malignancies in 2 patients (5%), and benign diseases in remaining 12 patients (29%), including 7 with amyloidomas. Patients with NHL were younger (p = 0.006) while smoking exposure was more prevalent in patients with lung carcinoma (p = 0.022). Patients with NHL had a higher number of PNs and more often manifested random distribution, cysts, ground-glass changes and consolidations. Upper and/or mid-lung location, spiculated borders, solitary nodule, increasing size, and higher SUVmean on FDG-PET scan were associated with lung carcinoma. At the end of follow-up (median 5.9 years), 8 patients (20%) had died and included 5 patients with lung carcinoma; no deaths were observed in the NHL group. CONCLUSIONS: The majority of biopsied PNs in patients with pSS were malignant, most commonly lymphomas. Smoking exposure, solitary nodule, and high FDG avidity were more frequently associated with lung carcinoma. The clinical context, CT and 18FDG-PET are complementary in the evaluation and management of PNs in patients with pSS.

Clinico-radiologic Features of Lung Disease Associated With Aspiration Identified on Lung Biopsy.

BACKGROUND: Aspiration-related lung diseases are commonly diagnosed presumptively based on the clinical context and radiologic findings. Limited data exist on the spectrum of clinico-radiologic presentations associated with aspiration. METHODS: This study reviewed all cases of aspiration identified on lung biopsy encountered at the Mayo Clinic between 2003 and 2017. Demographic and clinical features, including risk factors for aspiration, diagnoses suspected prior to biopsy, imaging findings, and microbiologic data, were analyzed. RESULTS: A total of 52 consecutive adult cases of aspiration identified on lung biopsy (histologic presence of food or other particulate matter) were included; patients' median age was 59 years (range, 22 to 79 years), 38% were women, and there were five lung transplant recipients. Of these, 63% were diagnosed according to results of surgical biopsy (including four cases of lobectomy) and 37% according to results of transbronchial biopsy. Aspiration was clinically suspected prior to biopsy in 35% of the subjects. Ninety percent of subjects had at least one identifiable risk factor for aspiration; gastroesophageal reflux disease was the most common (62%), followed by a structurally abnormal esophagogastric tract and the use of consciousness-impairing medications. Only 27% of patients reported dysphagia or choking. Chest CT imaging revealed a variety of parenchymal patterns, including bronchiolitis (42%), patchy consolidation (19%), and mass (15%). Of 25 patients undergoing a video-swallow evaluation, 14 (56%) had abnormal results with laryngeal penetration with or without aspiration. Microbial cultures obtained in 21 lung biopsy specimens yielded no pathogens. CONCLUSIONS: Aspiration can occur in the absence of subjective or demonstrable swallowing difficulties and manifest a broad spectrum of clinico-radiologic presentations.

Clinical and Histopathologic Features of Immune Checkpoint Inhibitor-related Pneumonitis.

Immune checkpoint inhibitors (ICIs) have revolutionized oncology, but are associated with immune-related adverse events. Clinically, pneumonitis is a well-recognized complication, but its histopathologic features are poorly understood. Institutional archives were searched for patients having ICI therapy and subsequent lung tissue sampling. After excluding infectious cases, 9 patients (5 women, median: 59 y) were identified with clinically suspected ICI-related pneumonitis. Clinical history, imaging, and pathology slides were reviewed. Patients received pembrolizumab (6 cases), nivolumab (1), ipilimumab followed by pembrolizumab (1), or pembrolizumab followed by nivolumab (1); the latter experienced pneumonitis with both agents. Treatment duration ranged from 1 to 33 cycles (median: 8). Three patients received concurrent chemotherapy and 1 received radiation; the remainder received ICI monotherapy. Symptoms were nonspecific; 2 patients were asymptomatic. Thoracic imaging showed bilateral ground glass or nodular opacities in all cases, often with pleural effusion. Histologically, organizing pneumonia was seen in 7 patients, all with subclinical or mild disease, admixed with vague non-necrotizing airspace granulomas in 3 cases; all 6 patients with follow-up did well. One patient had acute fibrinous pneumonitis and 1 had diffuse alveolar damage; both died. All 9 cases showed foamy macrophages and pneumocyte vacuolization; 6 had rare eosinophils. ICI-related pneumonitis presents as bilateral ground-glass opacities or nodules, and usually manifests as organizing pneumonia histopathologically, often with vague non-necrotizing airspace granulomas. Foamy macrophages and pneumocyte vacuolization are characteristic and rare eosinophils are often seen. Less commonly, acute fibrinous pneumonitis or diffuse alveolar damage can occur, which may be fatal.

Cowden Syndrome: A Cause of Pulmonary Cysts.

OBJECTIVE: To describe the pulmonary imaging findings in patients with Cowden syndrome (CS). MATERIALS AND METHODS: A retrospective review identified all patients with CS who underwent dedicated computed tomography examinations of the chest at our institution between January 2000 and October 2017. Patient demographics and imaging characteristics were identified through a review of the electronic medical record and relevant imaging. RESULTS: Fifteen patients (6 males/9 females; mean age 53 y) with a clinical diagnosis of CS were identified. Genetic confirmation of the PTEN mutation was available in 8/15 (50%) patients. Pulmonary cysts were present in 12/15 (80%) patients and in 8/8 (100%) patients with documented PTEN mutations. The cysts ranged in size from 4 to 63 mm and were <10 in 10/12 (83%). Cysts were distributed randomly in 10/12 (83%) cases. Solid pulmonary nodules were present in 13/15 (87%) patients and were distributed randomly in all cases. CONCLUSIONS: Pulmonary cysts and solid nodules are common in patients with CS. Cysts tend to be distributed randomly, few in number, and may have traversing vessels. These findings should not be interpreted as evidence of another underlying disorder in the setting of CS.

Managing Incidental Findings on Thoracic CT: Mediastinal and Cardiovascular Findings. A White Paper of the ACR Incidental Findings Committee.

The ACR Incidental Findings Committee presents recommendations for managing incidentally detected mediastinal and cardiovascular findings found on CT. The Chest Subcommittee was composed of thoracic radiologists who developed the provided guidance. These recommendations represent a combination of current published evidence and expert opinion and were finalized by informal iterative consensus. The recommendations address the most commonly encountered mediastinal and cardiovascular incidental findings and are not intended to be a comprehensive review of all incidental findings associated with these compartments. Our goal is to improve the quality of care by providing guidance on how to manage incidentally detected thoracic findings.

Correlation of pulmonary function and usual interstitial pneumonia computed tomography patterns in idiopathic pulmonary fibrosis.

BACKGROUND: Little is known about presenting 'inconsistent' or 'possible' usual interstitial pneumonia (UIP) computed tomography (CT) patterns advancing to 'consistent' UIP as disease progresses in idiopathic pulmonary fibrosis (IPF). We hypothesized that if 'consistent' UIP represented more advanced disease, such a pattern on presentation should also correlate with more severe pulmonary function test (PFT) abnormalities. MATERIAL AND METHODS: Consecutive IPF patients (2005-2013) diagnosed by international criteria with baseline PFT and CT were included. Presenting CTs were assessed by three expert radiologists for consensus UIP pattern ('consistent', 'possible', and 'inconsistent'). Approximation of individual and combined interstitial abnormalities was also performed with correlation of interstitial abnormalities and UIP CT pattern made with PFT findings and survival. RESULTS: Three-hundred and fifty patients (70% male) were included with a mean age of 68.3 years. Mean percent predicted forced vital capacity (FVC%) and diffusion capacity (DLCO%) was 64% and 45.5% respectively. Older age and male gender correlated more with 'consistent' UIP CT pattern. FVC% was not associated with any UIP pattern but did correlate with total volume of radiologist assessed interstitial abnormalities. DLCO% was lower in those with 'consistent' UIP pattern. A 'consistent' UIP CT pattern was also not independently predictive of survival after correction for age, gender, FVC%, and DLCO%. CONCLUSION: PFT findings appear to correlate with extent of radiologic disease but not specific morphologic patterns. Whether such UIP patterns represent different stages of disease severity or radiologic progression is not supported by coinciding pulmonary function decline.

Addition of the Fleischner Society Guidelines to Chest CT Examination Interpretive Reports Improves Adherence to Recommended Follow-up Care for Incidental Pulmonary Nodules.

RATIONALE AND OBJECTIVES: The study aimed to determine whether the addition of the Fleischner Society guidelines to chest computed tomography (CT) reports identifying incidental pulmonary nodules affects follow-up care. PATIENTS AND METHODS: Beginning in 2008, a template containing the Fleischner Society guidelines was added at the interpreting radiologist's discretion to chest CT reports describing incidental solid pulmonary nodules at our institution. The records of all medical centers in Olmsted county were used to capture the complete medical history of local patients >35 years old diagnosed with a pulmonary nodule from April 1, 2008 to October 1, 2011. Patients with a history of cancer or previously diagnosed nodule, or who died before follow-up, were excluded. Patients were categorized according to whether they did ("template group") or did not ("control group") have the template added. Nodule size and smoking history were used to determine recommended follow-up care. Differences in follow-up were compared between groups using Pearson's chi-square test. RESULTS: A total of 510 patients (276 in the template group, 234 in the control group) were included in the study. Only 198 patients (39%) received their recommended follow-up care. Template group patients were significantly more likely to receive recommended follow-up care compared to control group patients (45% vs 31%, P = .0014). Most patients whose management did not adhere to Fleischner Society guidelines did not receive a recommended follow-up chest CT (210 out of 312, 67%). CONCLUSIONS: The addition of the Fleischner Society guidelines to chest CT reports significantly increases the likelihood of receiving recommended follow-up care for patients with incidental pulmonary nodules. Additional education is needed to improve appropriate guideline utilization by radiologists and adherence by ordering providers.

Pulmonary nodule characterization, including computer analysis and quantitative features.

Pulmonary nodules are commonly detected in computed tomography (CT) chest screening of a high-risk population. The specific visual or quantitative features on CT or other modalities can be used to characterize the likelihood that a nodule is benign or malignant. Visual features on CT such as size, attenuation, location, morphology, edge characteristics, and other distinctive "signs" can be highly suggestive of a specific diagnosis and, in general, be used to determine the probability that a specific nodule is benign or malignant. Change in size, attenuation, and morphology on serial follow-up CT, or features on other modalities such as nuclear medicine studies or MRI, can also contribute to the characterization of lung nodules. Imaging analytics can objectively and reproducibly quantify nodule features on CT, nuclear medicine, and magnetic resonance imaging. Some quantitative techniques show great promise in helping to differentiate benign from malignant lesions or to stratify the risk of aggressive versus indolent neoplasm. In this article, we (1) summarize the visual characteristics, descriptors, and signs that may be helpful in management of nodules identified on screening CT, (2) discuss current quantitative and multimodality techniques that aid in the differentiation of nodules, and (3) highlight the power, pitfalls, and limitations of these various techniques.

Pulmonary fibrosis in dyskeratosis congenita: report of 2 cases.

Dyskeratosis congenita (DC) is a disorder of poor telomere maintenance and is related to 1 or more mutations that involve the vertebrate telomerase RNA component. Most affected patients develop mucocutaneous manifestations and cytopenias in the peripheral blood between 5 and 15 years of age. DC patients may also develop pulmonary complications including fibrotic interstitial lung disease and pulmonary vascular abnormalities. The radiologic and pathologic features of pulmonary fibrosis associated with DC are poorly defined. Herein, we report 2 new DC cases and suggest that the radiologic and histopathologic findings may resemble usual interstitial pneumonia but may not neatly fit into the current classification of interstitial lung disease.

Idiopathic pulmonary fibrosis: CT and risk of death.

PURPOSE: To investigate the prognostic value of quantitative computed tomographic (CT) scoring for the extent of fibrosis or emphysema in the context of a clinical model that includes the gender, age, and physiology ( GAP gender, age, and physiology model) of the patient. MATERIALS AND METHODS: Study cohorts were approved by local institutional review boards, and all patients provided written consent. This was a retrospective cohort study that included 348 patients (246 men, 102 women; mean age, 69 years ± 9) with idiopathic pulmonary fibrosis from two institutions. Fibrosis and emphysema visual scores were independently determined by two radiologists. Models were based on competing risks regression for death and were evaluated by using the C index and reclassification improvement. RESULTS: The CT- GAP gender, age, and physiology model (a modification of the original GAP gender, age, and physiology model that replaces diffusion capacity of carbon monoxide with CT fibrosis score) had accuracy comparable to that of the original GAP gender, age, and physiology model, with a C index of 70.3 (95% confidence interval: 66.4, 74.0); difference in C index compared with the GAP gender, age, and physiology model of -0.4 (95% confidence interval: -2.2, 3.4). The performance of the original GAP gender, age, and physiology model did not change significantly with the simple addition of fibrosis score, with a change in C index of 0.0 (95% confidence interval: -1.8, 0.5) or of emphysema score, with a change in C index of 0.0 [95% confidence interval: -1.3, 0.4]). CONCLUSION: CT fibrosis score can replace diffusion capacity of carbon monoxide test results in a modified GAP gender, age, and physiology model (the CT- GAP gender, age, and physiology model) with comparable performance. This may be a useful alternative model in situations where CT scoring is more reliable and available than diffusion capacity of carbon monoxide.