Follow-up Of Nodules Research Articles

Malignancy rates for Bethesda III and IV thyroid nodules: a retrospective study of the correlation between fine-needle aspiration cytology and histopathology

BackgroundFine-needle aspiration cytology (FNAC) has become a well-established modality in the diagnosis, staging and follow-up of thyroid nodules. FNAC outcomes are routinely classified using the Bethesda System for Reporting Thyroid Cytopathology (BSRTC), facilitating appropriate clinical management. Bethesda categories III and IV encompass varying risks of malignancy. This retrospective study established a possible association between these cytological categories and malignancy rates in patients treated at a single institution.MethodsOver a 6-year period, 11,627 FNAC procedures were performed on thyroid nodules. Of these, 814 (59.63%) patients were submitted to thyroidectomy. The nodules of 108 patients were classified as Bethesda category III and 47 patients as Bethesda category IV. Patient data were reviewed to establish a correlation between the FNAC results and the final histopathological analyses.ResultsThe rates of malignancy among patients who underwent surgery were 25% for category III and 27.6% for category IV, with no significant differences between categories (p = 0.67). The pathological parameters of malignant nodules, namely tumour type, size, encapsulation, invasion into the thyroid capsule, extrathyroidal extension and lymphovascular invasion did not significantly differ between the groups (p > 0.05).ConclusionsThis paper provides a more precise correlation of malignancy rates with thyroid nodules classified as Bethesda categories III and IV, as our findings are comparable to the literature, giving malignancy rates ranging from 10 to 30% for category III and 25–40% for category IV. Use of the BSRTC is heterogeneous across institutions, and there is some degree of subjectivity in the distinction between categories III and IV; therefore, it is crucial to estimate the rates of malignancy at each institution. Molecular assays are of increasing importance in determining the need for surgical intervention for thyroid lesions. Gene expression assays using FNAC material may demonstrate a high predictive value for cytologically indeterminate thyroid nodules diagnosed as Bethesda classes III and IV.

Determination of radiation dose and low-dose protocol for digital chest tomosynthesis using radiophotoluminescent (RPL) glass dosimeters

PurposeThis study aimed to determine a low-dose protocol for digital chest tomosynthesis (DTS). MethodsFive simulated nodules with a CT number of approximately 100 HU with size diameter of 3, 5, 8, 10, and 12 mm were inserted into an anthropomorphic chest phantom (N1 Lungman model), and then scanned by DTS system (Definium 8000) with varying tube voltage, copper filter thickness, and dose ratio. Three radiophotoluminescent (RPL) glass dosimeters, type GD-352 M with a dimension of 1.5 × 12 mm, were used to measure the entrance surface air kerma (ESAK) in each protocol. The effective dose (ED) was calculated using the recorded total dose-area-product (DAP). The signal-to-noise ratio (SNR) was determined for qualitative image quality evaluation. The image criteria and nodule detection capability were scored by two experienced radiologists. The selected low-dose protocol was further applied in a clinical study with 30 pulmonary nodule follow-up patients. ResultsThe average ESAK obtained from the standard default protocol was 1.68 ± 0.15 mGy, while an ESAK of 0.47 ± 0.02 mGy was found for a low-dose protocol. The EDs for the default and low-dose protocols were 313.98 ± 0.72 µSv and 100.55 ± 0.28 µSv, respectively. There were small non-significant differences in the image criteria and nodule detection scoring between the low-dose and default protocols interpreted by two radiologists. The effective dose of 98.87 ± 0.08 µSv was obtained in clinical study after applying the low-dose protocol. ConclusionsThe low-dose protocol obtained in this study can substantially reduce radiation dose while preserving an acceptable image quality compared to the standard protocol.

Cost-Effectiveness of Follow-Up for Subsolid Pulmonary Nodules in High-Risk Patients.

To evaluate the cost-effectiveness of a number of follow-up guidelines and variants for subsolid pulmonary nodules. We used a simulation model informed by data from the literature and the National Lung Screening Trial to simulate patients with ground-glass nodules (GGNs) detected at baseline computed tomography undergoing follow-up. The nodules were allowed to grow and develop solid components over time. We tested the guidelines generated by varying follow-up recommendations for low-risk nodules, that is, pure GGNs or those stable over time. For each guideline, we computed average US costs and quality-adjusted life-years (QALYs) gained per patient and identified the incremental cost-effectiveness ratios of those on the efficient frontier. In addition, we compared the costs and effects of the most recently released version of the Lung Computed Tomography Screening Reporting and Data System (Lung-RADS), version 1.1, with those of the previous version, 1.0. Finally, we performed sensitivity analyses of our results by varying several relevant parameters. Relative to the no follow-up scenario, the follow-up guideline system that was cost-effective at a willingness-to-pay of $100,000/QALY and had the greatest QALY assigned low-risk nodules a 2-year follow-up interval and stopped follow-up after 2 years for GGNs and after 5 years for part-solid nodules; this strategy yielded an incremental cost-effectiveness ratio of $99,970. Lung-RADS version 1.1 was found to be less costly but no less effective than Lung-RADS version 1.0. These findings were essentially stable under a range of sensitivity analyses. Ceasing follow-up for low-risk subsolid nodules after 2 to 5 years of stability is more cost-effective than perpetual follow-up. Lung-RADS version 1.1 was cheaper but similarly effective to version 1.0.

Interobserver agreement of the visual Herder scale for the assessment of solitary pulmonary nodules on 18F Fluorodeoxyglucose PET/computed tomography.

British Thoracic Society guidelines recommend 18F Fluorodeoxyglucose (F-FDG) PET/computed tomography (CT) for solitary pulmonary nodule (SPN) follow-up in high-risk individuals or if the CT Brock score is >10%. Nodule tracer uptake is assessed visually in comparison to the surrounding lung tissue and mediastinal blood pool (Herder score). This score is used to calculate the risk of malignancy and guide patient management. Despite its widespread use, there have been no studies to date looking at interobserver agreement using the Herder scale. F-FDG PET/CT studies of 100 consecutive patients imaged for the evaluation of SPN were retrospectively analysed. Anonymized images were reviewed independently by three Consultant Nuclear Medicine Radiologists and the Herder score was documented, along with a confidence score graded 1-3, where 1 indicated 'not at all confident' and 3 indicated 'very confident'. Interobserver agreement was assessed using interclass correlation coefficient modelling. There was complete reviewer agreement in 81% cases, and interclass correlation with Cronbach's alpha was excellent at 0.973 (95% confidence interval, 0.962-0.981). The agreement between pairs of reviewers was good and confidence scores using the Herder scale were high, with reviewers giving a confidence score of 3 in an average of 78% of cases. Our study suggests excellent interobserver agreement for use of the Herder scale in evaluating SPNs. Reviewer confidence scores were high reflecting high confidence in the use of the Herder scale for evaluating SPN.

Performance of contrast-enhanced ultrasound (CEUS) in assessing thyroid nodules: a systematic review and meta-analysis using histological standard of reference.

The present study was undertaken to systematically review the literature on the reliability of using contrast-enhanced ultrasound (CEUS) to assess thyroid nodules. To avoid the potential bias in studies using a cytological standard of reference, here we aimed to meta-analyze data from studies adopting histological diagnosis as the gold standard. A comprehensive literature exploration of PubMed and Scopus was conducted. The search was updated until June 2018 and references of the retrieved articles screened. Only original articles reporting the histological follow-up of nodules previously undergone CEUS evaluation were eligible for inclusion. Pooled sensitivity, specificity, PPV, and NPV of CEUS were calculated by DerSimonian and Laird method (random-effects model). The literature search retrieved 1885 articles, and 14 were included for the study. There were Chinese, Italian, German, and Austrian authors. All studies used SonoVue. The overall number of reported nodules was 1515, of which 775 were classified as positive at CEUS and 740 as negative. Pooled sensitivity, specificity, PPV, and NPV of CEUS were 85% (95% CI 83-88), 82% (95% CI 77-87), 83% (95% CI 77-88), and 85% (95% CI 81-88), respectively. Moderate inconsistency was present for specificity and PPV. There was publication bias for sensitivity and NPV. CEUS reaches good performance in discriminating between malignant and benign thyroid lesions.

Process Improvement for Communication and Follow-up of Incidental Lung Nodules.

Guideline-concordant follow-up of incidental lung nodules (ILNs) is suboptimal. We aimed to improve communication and tracking for follow-up of these common incidental findings detected on imaging examinations. We implemented a process improvement program for reporting and tracking ILNs at a large urban academic health care system. A multidisciplinary committee designed, tested, and implemented a multipart tracking system in the electronic health record (EHR) that included Fleischner Society management recommendations for each patient. Plan-do-study-act cycles addressed gaps in the follow-up of ILNs, broken into phases of developing and testing components of the conceived EHR toolkit. The program resulted in standardized text macros with discrete categories and recommendations for ILNs, with ability to track each case in a work list within the EHR. The macros incorporated evidence-based guidelines and also input of collaborating clinical referrers in the respective specialty. The ILN macro was used 3,964 times over the first 2 years, increasing from 104 to over 300 uses per month. Usage spread across all subspecialty divisions, with nonthoracic radiologists currently accounting for 80% (56 of 70) of the radiologists using the system and 31% (1,230 of 3,964) of all captured ILNs. When radiologists indicated ILNs as warranting telephone communication to provider offices, completion was documented in 100% of the cases captured in the EHR-embedded tracking report. An EHR-based system for managing incidental nodules enables case tracking with exact recommendations, provider communication, and completion of follow-up testing. Future efforts will target consistent radiologist use of the system and follow-up completion.

The diagnosis and treatment of lung cancer presented as ground-glass nodule.

Pulmonary nodules that manifest as ground-glass opacity are particularly challenging on account of their malignant potential and heterogeneous characteristics. The "ground-glass nodule-like" lung cancer is different from the conventional lung cancer. This review focuses on the radiologic and pathologic classifications of ground-glass nodules, along with the staging and clinical management of these lesions. In addition, we discuss the lung cancer high-risk population shift and follow-up of ground-glass nodules in the light of experience from screening trials. The standard of care surgical treatment of early lung cancer is still lobectomy with systematic lymph node dissection. However, a recent research has shown that some ground-glass nodules may be treated with sublobar resections or non-surgical treatment; these findings may expand the treatment options available in the future.

Multidisciplinary selection of pulmonary nodules for surgical resection: Diagnostic results and long-term outcomes

ObjectivePulmonary nodules found incidentally or by lung cancer screening differ in prevalence, risk profile, and diagnostic intervention. The results of surgical intervention for incidental versus screening lung nodules during multidisciplinary Pulmonary Nodule and Lung Cancer Screening Clinic (PNLCSC) follow-up have not been reported. MethodsAll patients evaluated at a PNLCSC from 2012 to 2018 following referral by primary care physicians, specialist physicians, or self-referral after computed tomography (CT) identified nodules on routine diagnostic CT (incidental group) or lung cancer screening CT (screening group) were included. Follow-up interval, invasive intervention, histology, postoperative events, survival, and recurrence were compared. ResultsOf 747 patients evaluated in the PNLCSC, 129 (17.2%) underwent surgical intervention. The surgical cohort consisted of 104 (80.6%) incidental and 25 (19.3%) screening patients followed over a mean of 122 and 70 days, respectively. More benign lesions were excised in the incidental group (20.2%, 21/104)—representing 3.3% (21/632) of all incidental nodules evaluated—than in the screening group (4%, 1/25) (P = .038). Operative mortality was zero. Among 99 patients with primary lung cancer, 87% (screening) and 86.8% (incidental) were pathologic stage Ia. Complete follow-up was available in 725 of 747 (97%), and no patient developed progressive disease. Disease-free survival at 5 years was 74.9% (incidental) and 89.3% (screening) (P = .48). ConclusionsA unique multidisciplinary PNLCSC for incidental and lung cancer screening–detected nodules with individualized risk assessment reliably identifies primary and metastatic tumors while exposing few patients to diagnostic excision for benign disease. Longer-term outcomes, strategies to limit radiation exposure, and cost control need further study.

Application of artificial intelligence in the diagnosis of multiple primary lung cancer.

Artificial intelligence (AI) based on deep learning, convolutional neural networks and big data has been increasingly effective in the diagnosis and treatment of multiple primary pulmonary nodules. In comparison to previous imaging systems, AI measures more objective parameters such as three‐dimensional (3D) volume, probability of malignant nodules, and possible pathological patterns, making the access to the properties of nodules more objective. In our retrospective study, a total of 53 patients with synchronous and metachronous multiple pulmonary nodules were enrolled of which 33 patients were confirmed by pathological tests to have primary binodules, and nine to have primary trinodules. A total of 15 patients had only one focus removed. The statistical results showed that the agreement in the AI diagnosis and postoperative pathological tests was 88.8% in identifying benign or malignant lesions. In addition, the probability of malignancy of benign lesions, preinvasive lesions (AAH, AIS) and invasive lesions (MIA, IA) was totally different (49.40±38.41% vs 80.22±13.55% vs 88.17±17.31%). The purpose of our study was to provide references for the future application of AI in the diagnosis and follow‐up of multiple pulmonary nodules. AI may represent a relevant diagnostic aid that shows more accurate and objective results in the diagnosis of multiple pulmonary nodules, reducing the time required for interpretation of results by directly displaying visual information to doctors and patients and together with the clinical conditions of MPLC patients, offering plans for follow‐up and treatment that may be more beneficial and reasonable for patients. Despite the great application potential in pneumosurgery, further research is needed to verify the accuracy and range of the application of AI.

No stone unturned: Nodule Net, an intervention to reduce loss to follow-up of lung nodules.

Inadequate lung nodule surveillance leads to diagnostic delays. We implemented a retrospective intervention program, Nodule Net, to improve surveillance in our hospital. 9,224 Chest computed tomography (CT) scans between January 1, 2015 and December 31, 2016 were manually reviewed for lung nodules. For patients without follow-up, charts were reviewed to assess follow-up. If follow-up appeared indicated, the clinician or patient was contacted, and follow-up was tracked. Lung nodules were identified on 5,101 (55%) of 9,224 scans. Follow-up was potentially indicated and not completed in 1,385 (27%). 183 (13%) were excluded after imaging review. 1,202 received outreach. Of the 801 (66%) with a provider in our system, 225 (27%) returned for follow-up. Nodules were stable in 199 (88%), new or growing in 23 (11%), resolved in 3 (1%), and stage 1 lung cancer in 2 (1%). 90 (11%) had follow-up outside our system and 431 (51%) had no follow-up due to a clinical contraindication. 55 (7%) have imaging pending and 14 (2%) are awaiting pulmonary evaluation. Of the 302 (25%) patients with providers outside our system, 121 (40%) had followed-up elsewhere. 146 (48%) had no follow-up due to a clinical reason. 35 (12%) providers did not respond to outreach. We identified 1,202 patients with lung nodules who needed follow-up over a two-year period. Compliance was more successful with providers within our hospital system. We recommend robust surveillance for patients to ensure follow-up is completed and clinical contraindications are well documented.

Long-term follow-up of persistent pulmonary pure ground-glass nodules with deep learning-assisted nodule segmentation.

To investigate the natural history of persistent pulmonary pure ground-glass nodules (pGGNs) with deep learning-assisted nodule segmentation. Between January 2007 and October 2018, 110 pGGNs from 110 patients with 573 follow-up CT scans were included in this retrospective study. pGGN automatic segmentation was performed on initial and all follow-up CT scans using the Dr. Wise system based on convolution neural networks. Subsequently, pGGN diameter, density, volume, mass, volume doubling time (VDT), and mass doubling time (MDT) were calculated automatically. Enrolled pGGNs were categorized into growth, 52 (47.3%), and non-growth, 58 (52.7%), groups according to volume growth. Kaplan-Meier analyses with the log-rank test and Cox proportional hazards regression analysis were conducted to analyze the cumulative percentages of pGGN growth and identify risk factors for growth. The mean follow-up period of the enrolled pGGNs was 48.7 ± 23.8months. The median VDT of the 52 pGGNs having grown was 1448 (range, 339-8640) days, and their median MDT was 1332 (range, 290-38,912) days. The 12-month, 24.7-month, and 60.8-month cumulative percentages of pGGN growth were 10%, 25.5%, and 51.1%, respectively, and they significantly differed among the initial diameter, volume, and mass subgroups (all p < 0.001). The growth pattern of pGGNs may conform to the exponential model. Lobulated sign (p = 0.044), initial mean diameter (p < 0.001), volume (p = 0.003), and mass (p = 0.023) predicted pGGN growth. Persistent pGGNs showed an indolent course. Deep learning can assist in accurately elucidating the natural history of pGGNs. pGGNs with lobulated sign and larger initial diameter, volume, and mass are more likely to grow. • The pure ground-glass nodule (pGGN) segmentation accuracy of the Dr. Wise system based on convolution neural networks (CNNs) was 96.5% (573/594). • The median volume doubling time (VDT) of 52 pure ground-glass nodules (pGGNs) having grown was 1448days (range, 339-8640days), and their median mass doubling time (MDT) was 1332days (range, 290-38,912days). The mean time to growth in volume was 854 ± 675days (range, 116-2856days). • The 12-month, 24.7-month, and 60.8-month cumulative percentages of pGGN growth were 10%, 25.5%, and 51.1%, respectively, and they significantly differed among the initial diameter, volume, and mass subgroups (all p values < 0.001). The growth pattern of pure ground-glass nodules may conform to exponential model.

Benign thyroid nodules in pediatric patients: determining best practices for repeat ultrasound evaluations.

Background The American Thyroid Association (ATA) recommendations for the follow-up of thyroid nodules with benign fine needle aspiration (FNA) cytology in children are largely based on adult data, despite well-characterized differences between thyroid nodules in adults and children. We aimed to determine the optimal time interval for repeat evaluation of an FNA-benign thyroid nodule in a pediatric patient. Methods This is a retrospective chart review of patients <19 years of age from 2003 to 2013 with a benign thyroid nodule by FNA cytology. Results We identified 43 patients with benign thyroid nodule cytology on FNA. The average age at diagnosis was 15.6 years, with female predominance (91%). Initial ultrasound (US) findings showed an average nodule size of 2.5 cm, 10% with calcifications, 37% hyperemia, 29% hypoechogenicity and 7% lymphadenopathy. Follow-up US was done in 42%. The first follow-up US occurred on average at 15 months after the initial US. Four patients had nodules with significant growth over time. One patient with papillary thyroid carcinoma (PTC) on final pathology initially had a decreasing nodule size, and then a subsequent increase in the nodule size after 4.5 years. Thyroid nodules were surgically removed in 33% with the final pathology showing a benign cytology in four patients, follicular adenoma in eight patients and PTC in two patients. Conclusions The majority of patients with benign thyroid nodules had no significant increase in nodule size in the first year of follow-up, including one patient who was subsequently found to have PTC. We recommend follow-up US at 1 year after initial presentation in low-risk pediatric patients with benign thyroid nodule cytology.

Cumulative Doses of Ionizing Radiation From Computed Tomography: A Population-Based Study

ObjectiveTo assess cumulative radiation doses from computed tomography (CT), patient characteristics, and clinical indications for CT in a population-based sample. Patients and MethodsA cohort study using medical records linkage through the Rochester Epidemiology Project was conducted to ascertain all CT examinations in Olmsted County, Minnesota, performed between January 1, 2004, and December 31, 2013, among all adults who were alive for 3 or more years after the end of follow-up (to exclude exposures preceding death). Ten-year cumulative effective ionizing radiation doses were estimated on the basis of typical doses per CT modality. Among patients with high doses (≥100 mSv/10 years), CT scans were reviewed for clinical setting, indications, and results. ResultsOf 54,447 adults (median age, 44.0 years at inclusion), 26,377 (48.4%) underwent at least one CT. Ten-year radiation doses from CT were 0.1 to 9.9 mSv in 15.8% of the population (8593 patients), 10 to 24.9 mSv in 16.9% (9502), 25 to 99.9 mSv in 13.8% (7492), and 100 mSv or greater in 1.9% (1041). Computed tomography of the abdomen and pelvis accounted for 67.2% of the estimated dose. In multivariable models, doses differed 1.21-fold to 2.16-fold between extreme categories of age, body mass index, education level, smoking status, and by race. Of 600 CTs in 200 patients with high doses, 70.5% were obtained for restaging of solid cancers and lymphoma, abdominal pain, infection, kidney stones, follow-up of nodules or masses, and chest pain/evaluation for pulmonary embolism. ConclusionExposure to ionizing radiation from CT occurred disproportionally in specific subgroups of the population. A limited number of clinical indications contributed the majority of radiation among adults with high doses.

Machine learning approach for distinguishing malignant and benign lung nodules utilizing standardized perinodular parenchymal features from CT.

Computed tomography (CT) is an effective method for detecting and characterizing lung nodules in vivo. With the growing use of chest CT, the detection frequency of lung nodules is increasing. Noninvasive methods to distinguish malignant from benign nodules have the potential to decrease the clinical burden, risk, and cost involved in follow-up procedures on the large number of false-positive lesions detected. This study examined the benefit of including perinodular parenchymal features in machine learning (ML) tools for pulmonary nodule assessment. Lung nodule cases with pathology confirmed diagnosis (74 malignant, 289 benign) were used to extract quantitative imaging characteristics from computed tomography scans of the nodule and perinodular parenchyma tissue. A ML tool development pipeline was employed using k-medoids clustering and information theory to determine efficient predictor sets for different amounts of parenchyma inclusion and build an artificial neural network classifier. The resulting ML tool was validated using an independent cohort (50 malignant, 50 benign). The inclusion of parenchymal imaging features improved the performance of the ML tool over exclusively nodular features (P<0.01). The best performing ML tool included features derived from nodule diameter-based surrounding parenchyma tissue quartile bands. We demonstrate similar high-performance values on the independent validation cohort (AUC-ROC=0.965). A comparison using the independent validation cohort with the Fleischner pulmonary nodule follow-up guidelines demonstrated a theoretical reduction in recommended follow-up imaging and procedures. Radiomic features extracted from the parenchyma surrounding lung nodules contain valid signals with spatial relevance for the task of lung cancer risk classification. Through standardization of feature extraction regions from the parenchyma, ML tool validation performance of 100% sensitivity and 96% specificity was achieved.

Tumor-derived Autoantibodies Identify Malignant Pulmonary Nodules.

Rationale: Screening for non-small cell lung cancer is associated with earlier diagnosis and reduced mortality but also increased harm caused by invasive follow-up of benign pulmonary nodules. Lung tumorigenesis activates the immune system, components of which could serve as tumor-specific biomarkers. Objectives: To profile tumor-derived autoantibodies as peripheral biomarkers of malignant pulmonary nodules. Methods: High-density protein arrays were used to define the specificity of autoantibodies isolated from B cells of 10 resected lung tumors. These tumor-derived autoantibodies were also examined as free or complexed to antigen in the plasma of the same 10 patients and matched benign nodule control subjects. Promising autoantibodies were further analyzed in an independent cohort of 250 nodule-positive patients. Measurements and Main Results: Thirteen tumor B-cell-derived autoantibodies isolated ex vivo showed greater than or equal to 50% sensitivity and greater than or equal to 70% specificity for lung cancer. In plasma, 11 of 13 autoantibodies were present both complexed to and free from antigen. In the larger validation cohort, 5 of 13 tumor-derived autoantibodies remained significantly elevated in cancers. A combination of four of these autoantibodies could detect malignant nodules with an area under the curve of 0.74 and had an area under the curve of 0.78 in a subcohort of indeterminate (8-20 mm in the longest diameter) pulmonary nodules. Conclusions: Our novel pipeline identifies tumor-derived autoantibodies that could effectively serve as blood biomarkers for malignant pulmonary nodule diagnosis. This approach has future implications for both a cost-effective and noninvasive approach to determine nodule malignancy for widespread low-dose computed tomography screening.

Long-Term Follow-Up of Ground-Glass Nodules After 5 Years of Stability

IntroductionSmall ground-glass nodules (GGNs) or those with an indeterminate risk on low-dose computed tomography (LDCT) of the chest are recommended at 5-year follow-up, but the rationale for follow-up beyond 5 years is unclear. MethodsAn observational study was conducted to investigate the natural course of GGNs that had been stable for 5 years by LDCT over 10 years. All eligible GGNs were detected during regular health checkups. Baseline characteristics were compared between GGNs with and without growth. Risk factors for GGN growth were evaluated. ResultsA total of 208 GGNs were detected in 160 participants. GGN growth was identified in 27 (13.0%) GGNs during a follow-up of 136 months on LDCT scans. In approximately 95% of these GGNs, the initial size was less than 6 mm, with 3.2 mm of growth over 8.5 years. Biopsies were performed in 3 of 27 GGNs, revealing adenocarcinoma. In 8 of 27 cases, GGN growth preceded the development of a new solid component. In a multivariate analysis, bubble lucency (p = 0.001), a history of cancer other than lung cancer (p = 0.036), and development of a new solid component (p < 0.001) were significant risk factors for GGN growth. ConclusionsGGNs should not be ignored, even when smaller than 6 mm and stable for 5 years, especially when a new solid component appears during follow-up.

Follow-up of incidental pulmonary nodules and association with mortality in a safety-net cohort

Background Though incidental pulmonary nodules are common, rates of guideline-recommended surveillance and associations between surveillance and mortality are unclear. In this study, we describe adherence (categorized as complete, partial, late and none) to guideline-recommended surveillance among patients with incidental 5-8 mm pulmonary nodules and assess associations between adherence and mortality. Methods This was a retrospective cohort study of 551 patients (≥35 years) with incidental pulmonary nodules conducted from September 1, 2008 to December 31, 2016, in an integrated safety-net health network. Results Of the 551 patients, 156 (28%) had complete, 87 (16%) had partial, 93 (17%) had late and 215 (39%) had no documented surveillance. Patients were followed for a median of 5.2 years [interquartile range (IQR), 3.6-6.7 years] and 82 (15%) died during follow-up. Adjusted all-cause mortality rates ranged from 2.24 [95% confidence interval (CI), 1.24-3.25] deaths per 100 person-years for complete follow-up to 3.30 (95% CI, 2.36-4.23) for no follow-up. In multivariable models, there were no statistically significant associations between the levels of surveillance and mortality (p > 0.16 for each comparison with complete surveillance). Compared with complete surveillance, adjusted mortality rates were non-significantly increased by 0.45 deaths per 100 person-years (95% CI, -1.10 to 2.01) for partial, 0.55 (95% CI, -1.08 to 2.17) for late and 1.05 (95% CI, -0.35 to 2.45) for no surveillance. Conclusions Although guideline-recommended surveillance of small incidental pulmonary nodules was incomplete or absent in most patients, gaps in surveillance were not associated with statistically significant increases in mortality in a safety-net population.

Management of incidental pulmonary nodule in CT: a survey by the Italian College of Chest Radiology.

The aim of this study is to present the results of the Italian survey on the management of pulmonary nodules incidentally identified at computed tomography (CT). An online electronic survey, consisting of 23 multiple-choice questions, was created using the SurveyMonkey web-based tool. The questionnaire was developed by the Board of the Italian College of Chest Radiology of the Italian Society of Medical and Interventional Radiology (SIRM) and by an experienced group of Italian Academic Chest Radiologists. The link to the online electronic survey was submitted by email to all the SIRM members. A total of 767 radiologists, corresponding to 7.5% of all the SIRM members, participated in the online survey. The majority of participants (92%) routinely describe the attenuation of pulmonary nodules in the report, and 84.1% recommend the further follow-up, with 92.7% of respondents taking CT nodule morphological features into consideration. The 57.7% of participants adhere to the Fleischner Society guidelines for the management of incidental pulmonary nodules. However, 56.6% and 75.6% of respondents have a more cautious approach than that recommended by the guidelines and tend to use a shorter follow-up for both solid and ground-glass nodules, respectively. Finally, 94.5% of participants favor congresses and refresher courses dedicated to insights on lung nodule diagnosis and management. This survey demonstrates that the management of pulmonary nodules incidentally detected on CT is still complex and controversial. The majority of SIRM members express a need for an update on this topic.

MR Volumetry of Lung Nodules: A Pilot Study.

Introduction: Computed tomography (CT) is currently the reference modality for the detection and follow-up of pulmonary nodules. While 2D measurements are commonly used in clinical practice to assess growth, increasingly 3D volume measurements are being recommended. The goal of this pilot study was to evaluate preliminarily the capabilities of 3D MRI using ultra-short echo time for lung nodule volumetry, as it would provide a radiation-free modality for this task.Material and Methods: Artificial nodules were manufactured out of Agar and measured using an ultra-short echo time MRI sequence. CT data were also acquired as a reference. Image segmentation was carried out using an algorithm based on signal intensity thresholding (SIT). For comparison purposes, we also performed manual slice by slice segmentation. Volumes obtained with MRI and CT were compared. Finally, the volumetry of a lung nodule was evaluated in one human subject in comparison with CT.Results: Using the SIT technique, minimal bias was observed between CT and MRI across the entire range of volumes (2%) with limits of agreement below 14%. Comparison of manually segmented MRI and CT resulted in a larger bias (8%) and wider limits of agreement (−23% to 40%). In vivo, nodule volume differed of <16% between modalities with the SIT technique.Conclusion: This pilot study showed very good concordance between CT and UTE-MRI to quantify lung nodule volumes, in both a phantom and human setting. Our results enhance the potential of MRI to quantify pulmonary nodule volume with similar performance to CT.

Follow-up of large thyroid nodules without surgery: Patient selection and long-term outcomes.

The management of large thyroid nodules remains controversial. Mandatory resection is recommended by some authors. All patients with thyroid nodules ≥3 cm between January 2009 and January 2013 were followed until August 2017. Follow-up data were collected using an integrated hospital-community system. A total of 141 nodules were included. Of these, 37/141 (26%) nodules were initially referred to surgery, resulting in a 32% malignancy rate (12/37). The remaining 104/141 (74%) were referred to follow-up. During the follow-up period, 24 additional operations were done, resulting in a 4% malignancy rate (1/24). An indication of nonbenign cytology was significantly associated with malignancy compared with other indications. Median follow-up was 53.5 months. No patient developed regional or distal diseases. The mean change in nodule size during the follow-up period was a 7% reduction, with no significant trend of change over time. Careful patient selection based on clinical, sonographic, and cytologic features can reduce diagnostic surgery allowing for safe follow-up of large thyroid nodules without surgery.