How to deal with incidentally detected pulmonary nodules less than 10mm in size on CT in a healthy person. Lung Cancer. 2008;60:151-159. [PMID: 18359124 DOI: 10.1016/j.lungcan.2008.01.020]

Which is a real valuable screening tool for lung cancer and measure thoracic diseases, chest radiography or low-dose computed tomography?: A review on the current status of Japan and other countries

Chest radiography (CR) has been used as a screening tool for lung cancer and the use of low-dose computed tomography (LDCT) is not recommended in Japan. We need to reconsider whether CR really contributes to the early detection of lung cancer. In addition, we have not well discussed about other major thoracic disease detection by CR and LDCT compared with lung cancer despite of its high frequency. We review the usefulness of CR and LDCT as veridical screening tools for lung cancer and other thoracic diseases. In the case of lung cancer, many studies showed that LDCT has capability of early detection and improving outcomes compared with CR. Recent large randomized trial also supports former results. In the case of chronic obstructive pulmonary disease (COPD), LDCT contributes to early detection and leads to the implementation of smoking cessation treatments. In the case of pulmonary infections, LDCT can reveal tiny inflammatory changes that are not observed on CR, though many of these cases improve spontaneously. Therefore, LDCT screening for pulmonary infections may be less useful. CR screening is more suitable for the detection of pulmonary infections. In the case of cardiovascular disease (CVD), CR may be a better screening tool for detecting cardiomegaly, whereas LDCT may be a more useful tool for detecting vascular changes. Therefore, the current status of thoracic disease screening is that LDCT may be a better screening tool for detecting lung cancer, COPD, and vascular changes. CR may be a suitable screening tool for pulmonary infections and cardiomegaly.

Evaluation of chest radiography and low-dose computed tomography as valuable screening tools for thoracic diseases

BACKGROUND

Recent studies have shown that low-dose computed tomography (LDCT) is effective for the early detection of lung cancer. However, the utility of chest radiography (CR) and LDCT for other thoracic diseases has not been as well investigated as it has been for lung cancer. This study aimed to clarify the usefulness of the veridical method in the screening of various thoracic diseases.

METHODS

Among individuals who had received general health checkups over a 10-year period, those who had undergone both CR and LDCT were selected for analysis. The present study included 4317 individuals (3146 men and 1171 women). We investigated cases in which abnormal opacity was detected on CR and/or LDCT.

RESULTS

A total of 47 and 124 cases had abnormal opacity on CR and LDCT, respectively. Among these, 41 cases in which the abnormal opacity was identified by both methods contained 20 treated cases. Six cases had abnormalities only on CR, and none of the cases required further treatment. Eighty-three cases were identified using LDCT alone. Of these, many cases, especially those over the age of 50 years, were diagnosed with thoracic tumors and chronic obstructive pulmonary disease, which required early treatment. In contrast, many cases of pulmonary infections have improved spontaneously, without any treatment.

CONCLUSION

These results revealed that LDCT allowed early detection of thoracic tumors and chronic obstructive pulmonary disease, especially in individuals over the age of 50 years. CR is still a useful imaging modality for other thoracic diseases, especially in individuals under the age of 49 years.

Computed tomography-guided cutting needle biopsy for lung nodules: when the biopsy-based benign results are real benign

Background

Computed tomography (CT)-guided cutting needle biopsy (CNB) is an effective diagnostic method for lung nodules (LNs). The false-negative rate of CT-guided lung biopsy is reported to be up to 16%. This study aimed to determine the predictors of true-negative results in LNs with CNB-based benign results.

Methods

From January 2011 to December 2015, 96 patients with CNB-based nonspecific benign results were included in this study as the training group to detect predictors of true-negative results. From January 2016 to December 2018, an additional 57 patients were included as a validation group to test the reliability of the predictors.

Results

In the training group, a total of 96 patients underwent CT-guided CNB for 96 LNs. The CNB-based results were true negatives for 82 LNs and false negatives for 14 LNs. The negative predictive value of the CNB-based benign results was 85.4% (82/96). Univariate and multivariate logistic regression analyses revealed that CNB-based granulomatous inflammation (P = 0.013, hazard ratio = 0.110, 95% confidential interval = 0.019–0.625) was the independent predictor of true-negative results. The area under the receiver operator characteristic (ROC) curve was 0.697 (P = 0.019). In the validation group, biopsy results for 47 patients were true negative, and 10 were false negative. When the predictor was used on the validation group, the area under the ROC curve was 0.759 (P = 0.011).

Conclusions

Most of the CNB-based benign results were true negatives, and CNB-based granulomatous inflammation could be considered a predictor of true-negative results.

Preoperative computed tomography-guided coil localization of sub-centimeter lung nodules

Introduction

Lung nodules (LNs) are often identified in at-risk patients via low-dose computed tomography (CT) approaches. Sub-centimeter (≤ 1 cm) LNs (SCLNs) are particularly difficult for surgeons and pathologists to accurately treat and diagnose.

Aim

To evaluate the clinical efficacy of preoperative CT-guided coil localization for SCLNs.

Material and methods

Between January 2015 and December 2019, consecutive patients at our hospital with SCLNs underwent CT-guided coil localization followed by video-assisted thoracoscopic surgery (VATS). We then assessed rates of technical success corresponding to the localization and VATS-guided wedge resection procedures and measured rates of localization-related complications.

Results

In total, 52 patients were analyzed in this study, with 66 total SCLNs being localized with one coil each. CT-guided coil localization achieved a 93.9% (62/66) technical success rate, and a mean duration of 15.2 ±4.5 minutes. Following coil localization, 6 (11.5%) patients experienced pneumothorax and 4 (7.7%) patients suffered hemoptysis, with 1 patient requiring the insertion of a chest tube to alleviate pneumothorax. VATS-guided wedge resection was associated with a 100% technical success rate, and no patients needed to undergo conversion to thoracotomy. One-stage VATS-guided wedge resection was conducted in the 12 patients with multiple SCLNs. The mean VATS duration was 128.9 ±66.7 minutes, and mean blood loss associated with this procedure was 83.0 ±67.7 ml.

Conclusions

Preoperative CT-guided coil localization can safely and effectively achieve high rates of success when conducting the diagnostic VATS wedge resection of SCLNs.

Developing of risk models for small solid and subsolid pulmonary nodules based on clinical and quantitative radiomics features

Background

Accurate evaluation of pulmonary nodule malignancy is important for lung cancer management. This current study aimed to develop risk models for small solid and subsolid pulmonary nodules based on clinical and quantitative radiomics features.

Methods

This study enrolled 5–20 mm pulmonary nodules detected on thoracic high-resolution computed tomography (HRCT), which were all confirmed pathologically. There were 548 solid nodules (242 malignant vs. 306 benign) and 623 subsolid nodules (SSNs 519 malignant vs. 104 benign). Relevant clinical characteristics were recorded. The CT image prior to the initial treatment was chosen for manual segmentation of the targeted nodule using the ITK-SNAP software. Subsequently, the marked image was processed to quantitatively extract 1218 radiomics features using PyRadiomics. We performed five-fold cross-validation to select potential predictors from clinical and radiomics features using the LASSO method and to evaluate the performance of the established models. In total, four types of models were tried: random forest, XGBOOST, SVM, and logistic models. The established models were compared with the Mayo model.

Results

Lung cancer risk models were developed among four nodule groups: all nodules (410 benign vs. 761 malignant; 1:1.86), nodules ≤10 mm (185 benign vs. 224 malignant; 1:1.21), solid nodules (306 benign vs. 242 malignant; 1.26:1), and SSNs (104 benign vs. 104 malignant; 1:1 matched). Significant clinical and radiomics predictors were selected for each group. The accuracy, area under the ROC curve, sensitivity, and specificity of the best model on validation dataset was 0.86, 0.91, 0.93, 0.73 for all nodules (XGBOOST), 0.82, 0.90, 0.86, 0.76 for nodules ≤10 mm (XGBOOST), 0.80, 0.89, 0.78, 0.82 for solid nodules (XGBOOST) and 0.70, 0.73, 0.73, 0.67 for SSNs (Random Forest). Except for the SSN models, the established clinical-radiomics models were superior to the Mayo model.

Conclusions

Predictive models based on both clinical and radiomics features can be used to assess the malignancy of small solid and subsolid pulmonary nodules, even for nodules that are 10 mm or smaller.

Trans-scapular approach coil localization for scapular-blocked pulmonary nodules: a retrospective study

BACKGROUND

Preoperative computed tomography (CT)-guided coil localization (CL) is commonly used to facilitate video-assisted thoracoscopic surgery (VATS)-guided diagnostic wedge resection (WR) of pulmonary nodules (PNs). When a scapular-blocked PN (SBPN) is localized, the trans-scapular CL (TSCL) is commonly performed. In this study, we investigated the safety, feasibility, and clinical efficacy of preoperative CT-guided TSCL for SBPNs.

MATERIALS AND METHODS

From January 2014 to September 2020, a total of 152 patients with PNs underwent CT-guided CL prior to VATS-guided WR. Of these patients, 14 had SBPNs and underwent the TSCL procedure.

RESULTS

A total of 14 SBPNs were localized in the 14 patients. The mean diameter of the 14 SBPNs was 7.4 ± 2.4 mm. The technical success rate of the scapula puncture was 100%. No complications occurred near the scapula. The technical success rate of CL was 92.9%. One coil dropped off when performing the VATS procedure. The mean duration of the TSCL was 14.2 ± 2.7 min. Two patients (14.3%) developed asymptomatic pneumothorax after TSCL. The technical success rate of VATS-guided WR was 92.9%. The patient who experienced technical failure of TSCL directly underwent lobectomy. The mean duration of the VATS was 90.0 ± 42.4 min and the mean blood loss was 62.9 ± 37.2 ml. The final diagnoses of the 14 SBPNs included invasive adenocarcinoma (n = 4), adenocarcinoma in situ (n = 9), and benign disease (n = 1).

CONCLUSIONS

Preoperative CT-guided TSCL is a safe and simple procedure that can facilitate high success rates of VATS-guided WR of SBPNs.

Predicting Lung Cancer Risk of Incidental Solid and Subsolid Pulmonary Nodules in Different Sizes

Objective

Malignancy prediction models for pulmonary nodules are most accurate when used within nodules similar to those in which they were developed. This study was to establish models that respectively predict malignancy risk of incidental solid and subsolid pulmonary nodules of different size.

Materials and Methods

This retrospective study enrolled patients with 5-30 mm pulmonary nodules who had a histopathologic diagnosis of benign or malignant. The median time to lung cancer diagnosis was 25 days. Four training/validation datasets were assembled based on nodule texture and size: subsolid nodules (SSNs) ≤15 mm, SSNs between 15 and 30 mm, solid nodules ≤15 mm and those between 15 and 30 mm. Univariate logistic regression was used to identify potential predictors, and multivariate analysis was used to build four models.

Results

The study identified 1008 benign and 1813 malignant nodules from a single hospital, and by random selection 1008 malignant nodules were enrolled for further analysis. There was a much higher malignancy rate among SSNs than solid nodules (rate, 75% vs 39%, P<0.001). Four distinguishing models were respectively developed and the areas under the curve (AUC) in training sets and validation sets were 0.83 (0.78-0.88) and 0.70 (0.61-0.80) for SSNs ≤15 mm, 0.84 (0.74-0.93) and 0.72 (0.57-0.87) for SSNs between 15 and 30 mm, 0.82 (0.77-0.87) and 0.71 (0.61-0.80) for solid nodules ≤15 mm, 0.82 (0.79-0.85) and 0.81 (0.76-0.86) for solid nodules between 15 and 30 mm. Each model showed good calibration and potential clinical applications. Different independent predictors were identified for solid nodules and SSNs of different size.

Conclusion

We developed four models to help characterize subsolid and solid pulmonary nodules of different sizes. The established models may provide decision-making information for thoracic radiologists and clinicians.

Diagnostic Yield of Computed Tomography-Guided Percutaneous Lung Biopsy in Patients With Prior Nondiagnostic Transbronchial Biopsy

PURPOSE

The purpose of this study was to assess the diagnostic yield of computed tomography (CT)-guided core needle biopsy (CNB) for initial transbronchial biopsy (TBB)-based nondiagnostic lung lesions.

METHODS

From January 2014 to December 2017, 101 consecutive patients with initial TBB-based nondiagnostic lung lesions underwent CT-guided CNB. All procedures were performed with an 18G core needle by a chest radiologist with more than 5 years of experience. The CT-guided CNB was performed within 30 days after the initial TBB. In total, 90 and 11 central and peripheral lung lesions were observed, respectively. The mean ± SD diameter of these lesions was 58.8 ± 21.8 mm. The diagnostic yield of CT-guided CNB was assessed.

RESULTS

Computed tomography-guided CNB provided a definite diagnosis for 63 (62.4%) of the 101 lesions. The 63 CNB-based lesion diagnoses included malignant (n = 57) and specific benign (n = 6) lesions. The remaining 38 CNB-based nondiagnostic lesions included nonspecific benign (n = 35) and suspected malignant (n = 3) lesions. The 38 CNB-based nondiagnostic lesions were confirmed by surgery (n = 5), repeat CNB (n = 5), or CT follow-up (n = 28). The mean ± SD follow-up was 9.9 ± 7.3 months. Based on the final diagnosis, 67 lesions were malignant and 34 lesions were benign. The sensitivity, specificity, and accuracy of CT-guided CNB were 89.6% (60/67), 100% (34/34), and 93.1% (94/101), respectively.

CONCLUSIONS

Computed tomography-guided CNB is a useful diagnostic modality for accurate diagnosis of lung lesions with inconclusive pathologic results after initial TBB.

Computed tomography-guided biopsy for sub-centimetre lung nodules: Technical success and diagnostic accuracy

INTRODUCTION

The differentiation of benign and malignant sub-centimetre (≤10 mm) lung nodules (SCLNs) is challenging. Computed tomography (CT)-guided biopsy has been widely used for the diagnosis of lung nodules or masses. However, studies regarding CT-guided biopsies for SCLNs are still lacking.

OBJECTIVES

To evaluate the feasibility and diagnostic accuracy of CT-guided biopsies for SCLNs.

METHODS

From December 2011 to October 2017, 102 patients with SCLNs underwent CT-guided lung biopsies. Data on technical success, diagnostic performance and procedure-related complications were collected and analysed.

RESULTS

The technical success rate of CT-guided biopsy for SCLNs was 99% (101/102). One patient failed to undergo the procedure. A total of 101 SCLNs in 101 patients were examined. The biopsy diagnostic results included 38 malignant cases, 1 suspected malignant case, 5 specific benign cases and 57 non-specific benign cases. The final diagnoses included 49 malignant cases, 49 benign cases and 3 cases of undiagnosed lesions. The sensitivity, specificity and overall diagnostic accuracy were 80% (39/49), 100% (49/49) and 90% (88/98), respectively. Based on the univariate and multivariate logistic regression analyses, the independent risk factors for diagnostic failure were small tissue sample numbers (P = 0.048) and procedure-related hemoptysis (P = 0.004). Pneumothorax was found in 13 patients (13%). Based on the univariate and multivariate logistic regression analyses, the independent risk factor for pneumothorax was the decubitus position (P = 0.011). Hemoptysis was found in seven patients (7%).

CONCLUSIONS

CT-guided biopsy is a safe and highly accurate diagnostic method for SCLNs.

Clinical characteristics and work-up of small to intermediate-sized pulmonary nodules in a Chinese dedicated cancer hospital

Objectives: To evaluate the characteristics and work-up of small to intermediate-sized pulmonary nodules in a Chinese dedicated cancer hospital. Methods: Patients with pulmonary nodules 4-25 mm in diameter detected via computed tomography (CT) in 2013 were consecutively included. The analysis was restricted to patients with a histological nodule diagnosis or a 2-year follow-up period without nodule growth confirming benign disease. Patient information was collected from hospital records. Results: Among the 314 nodules examined in 299 patients, 212 (67.5%) nodules in 206 (68.9%) patients were malignant. Compared to benign nodules, malignant nodules were larger (18.0 mm vs. 12.5 mm, P < 0.001), more often partly solid (16.0% vs. 4.7%, P < 0.001) and more often spiculated (72.2% vs. 41.2%, P < 0.001), with higher density in contrast-enhanced CT (67.0 HU vs. 57.5 HU, P = 0.015). Final diagnosis was based on surgery in 232 out of 314 (73.9%) nodules, 166 of which were identified as malignant [30 (18.1%) stage III or IV] and 66 as benign. In 36 nodules (11.5%), diagnosis was confirmed by biopsy and the remainder verified based on stability of nodule size at follow-up imaging (n = 46, 14.6%). Among 65 nodules subjected to gene (EGFR) mutation analyses, 28 (43.1%) cases (EGFR19 n = 13; EGFR21 n = 15) were identified as EGFR mutant and 37 (56.9%) as EGFR wild-type. Prior to surgery, the majority of patients [n = 194 (83.6%)] received a contrast-enhanced CT scan for staging of both malignant [n = 140 (84.3%)] and benign [n = 54 (81.8%)] nodules. Usage of positron emission tomography (PET)-CT was relatively uncommon [n = 38 (16.4%)]. Conclusions: CT-derived nodule assessment assists in diagnosis of small to intermediate- sized malignant pulmonary nodules. Currently, contrast-enhanced CT is commonly used as the sole diagnostic confirmation technique for pre-surgical staging, often resulting in surgery for late-stage disease and unnecessary surgery in cases of benign nodules.

What's New on Quantitative CT Analysis as a Tool to Predict Growth in Persistent Pulmonary Subsolid Nodules? A Literature Review

Pulmonary subsolid nodules (SSNs) are observed not infrequently on thin-section chest computed tomography (CT) images. SSNs persisting after a follow-up period of three to six months have a high likelihood of being pre-malignant or malignant lesions. Malignant SSNs usually represent the histologic spectrum of pulmonary adenocarcinomas, and pulmonary adenocarcinomas presenting as SSNs exhibit quite heterogeneous behavior. In fact, while most lesions show an indolent course and may grow very slowly or remain stable for many years, others may exhibit significant growth in a relatively short time. Therefore, it is not yet clear which persistent SSNs should be surgically removed and for how many years stable SSNs should be monitored. In order to solve these two open issues, the use of quantitative analysis has been proposed to define the "tailored" management of persistent SSNs. The main purpose of this review was to summarize recent results about quantitative CT analysis as a diagnostic tool for predicting the behavior of persistent SSNs. Thus, a literature search was conducted in PubMed/MEDLINE, Scopus, and Web of Science databases to find original articles published from January 2014 to October 2019. The results of the selected studies are presented and compared in a narrative way.

Implementation of a Standardized Template for Reporting of Incidental Pulmonary Nodules: Feasibility, Acceptability, and Outcomes

OBJECTIVE

Incidental pulmonary nodules (IPNs) are common. Up to 70% are not followed up according to current guidelines. Follow-up recommendations are based on the characteristics of the patient and the IPN. However, many IPNs are incompletely characterized in CT reports. Structured radiology reports have been shown to reduce missing information. We sought to improve IPN reporting by assessing the feasibility, acceptability, and effectiveness of a structured dictation template to increase the presence of six key nodule descriptors.

METHODS

We performed a mixed methods, pre- and postimplementation assessment. A template was developed with a multidisciplinary group based on Fleischner Society guidelines. A standardized checklist was used to determine the presence of documented descriptors pre- and postimplementation for sequential radiology reports of patients with an IPN present (n = 400 pre-implementation and n = 400 postimplementation) on a CT performed at the Minneapolis Veterans Affairs Health Care System. We conducted qualitative interviews with radiologists (n = 4) and members of the lung nodule tracking team (n = 2) to elicit their experiences of the template implementation process.

RESULTS

The proportion of radiology reports including all six elements increased from 12% to 47% (P < .001). Postimplementation, the template was used in 40% of interpretations involving lung nodules, 67% of follow-up scans, and 8% of initial identifications. Response to the template was overall positive.

DISCUSSION

Use of a dictation template seems to be effective in increasing compliance with full IPN documentation, streamlining the follow-up process. Low utilization rates of the template for initial nodule identification is a limitation, which may be combated through clearer communication and advances in technology.

Solid Indeterminate Pulmonary Nodules of Less Than 300 mm3: Application of Different Volume Doubling Time Cut-offs in Clinical Practice

In the British Thoracic Society guidelines for incidental pulmonary nodules, volumetric analysis has become the recommended method for growth assessment in solid indeterminate pulmonary nodules (SIPNs) <300 mm³. In these guidelines, two different volume doubling time (VDT) cut-offs, 400 and 600 days, were proposed to differentiate benign from malignant nodules. The present study aims to evaluate the performance of these VDT cut-offs in a group of SIPNs <300 mm³ which were incidentally detected in a routine clinical setting. During a 7-year period, we retrospectively selected 60 patients with a single SIPN <300 mm³. For each SIPN, the volume and VDT were calculated using semiautomatic software throughout the follow-up period, and the performance of the 400- and 600-day VDT cut-offs was compared. In the selected sample, there were 38 benign and 22 malignant nodules. In this group of nodules, the sensitivity, negative predictive value and accuracy of the 600-day VDT cut-off were higher than those of the 400-day VDT cut-off. Therefore, in the management of SIPNs <300 mm³ which were incidentally detected in a clinical setting, the 600-day VDT cut-off was better at differentiating benign from malignant nodules than the 400-day VDT cut-off, by reducing the number of false negatives.

Solid Indeterminate Pulmonary Nodules Less Than or Equal to 250 mm3: Application of the Updated Fleischner Society Guidelines in Clinical Practice

Background

The latest version of the Fleischner Society guidelines for management of incidental pulmonary nodules was published in 2017. The main purpose of these guidelines is to reduce the number of unnecessary computed tomography (CT) examinations during the follow-up of small indeterminate nodules.

Objective

The present study aimed to evaluate the performance of these guidelines for management of solid indeterminate pulmonary nodules (SIPNs) ≤ 250 mm³.

Materials and Methods

During a 7-year period, we retrospectively reviewed the chest CT scans of 672 consecutive patients with SIPNs. The study sample was selected according to the following inclusion criteria: solitary SIPN; diameter ≥ 3 mm; volume ≤ 250 mm³; two or more CT scans performed with the same scanner and same acquisition/reconstruction protocol; thin-section 1-mm images in DICOM format; histologic diagnosis or follow-up ≥ 2 years; and no oncological history. Applying these criteria, a total of 27 patients with single SIPNs ≤ 250 mm³ were enrolled. For each SIPN, the volume and doubling time were calculated using semiautomatic software throughout the follow-up period. For each SIPN, we applied the Fleischner Society guidelines, and the recommended management was compared to what was actually done.

Results

A significant volumetric increase was detected in 5/27 (18.5%) SIPNs; all growing nodules were observed in high-risk patients. In these SIPNs, a histologic diagnosis of malignancy was obtained. Applying the Fleischner Society recommendations, all five malignant nodules would have been identified. None of the SIPNs < 100 mm³ in low-risk patients showed significant growth during the follow-up period. The application of the new guidelines would have led to a significant reduction in follow-up CT examinations (Hodges-Lehmann median difference, -2 CT scans; p = 0.0001).

Conclusion

The application of the updated Fleischner Society guidelines has been shown to be effective in the management of SIPNs ≤ 250 mm³ with a significant reduction in radiation dose.

Comparison Between Radiological Semantic Features and Lung-RADS in Predicting Malignancy of Screen-Detected Lung Nodules in the National Lung Screening Trial

RATIONALE

Lung computed tomography (CT) Screening Reporting and Data System (lung-RADS) has standardized follow-up and management decisions in lung cancer screening. To date, little is known how lung-RADS classification compares with radiological semantic features in risk prediction and diagnostic discrimination.

OBJECTIVES

To compare the performance of radiological semantic features and lung-RADS in predicting nodule malignancy in lung cancer screening.

METHODS

We used data and low-dose CT (LDCT) images from the National Lung Screening Trial (NLST). The training cohort contained 60 patients with screen-detected incident lung cancers who had a positive baseline screen (T0) that was not diagnosed and then was diagnosed at second follow-up (T2), and 139 nodule-positive controls who had 3 consecutive positive screens (T0 to T2) that were not diagnosed as lung cancer. The testing cohort included 40 patients with incident lung cancers that were diagnosed at first follow-up (T1) and 40 nodule-positive controls. Twenty-four semantic features were scored on a point scale from the LDCT images. Multivariable linear predictor model was built on the semantic features and the performances were compared with lung-RADS in 3 screening rounds. We also combined non-size-based semantic features with lung-RADS to improve malignancy detection.

RESULTS

At T0, the average area under the receiver operating characteristic curve (AUROC) for border definition in risk prediction was 0.72. The average AUROC for contour at T1 in risk prediction and T2 in diagnostic discrimination was 0.82 and 0.88, respectively. By comparison, the average AUROC of lung-RADS at T0, T1 and T2 were 0.60, 0.76 and 0.87, respectively. The combined model of the semantic features and lung-RADS shows improvement with AUROCs of 0.74, 0.88 and 0.96 at T0, T1, and T2, respectively, achieved by adding border definition (at T0) or contour (at T1 and T2).

CONCLUSION

We find semantic features defined by border definition and contour performed similar to lung-RADS at follow-up time point and outperformed lung-RADS at baseline. These semantics alongside of lung-RADS shows improved performance to detect malignancy.

[Surgical Treatment of Small Pulmonary Nodules Under Video-assisted Thoracoscopy (A Report of 129 Cases)]

背景与目的

影像技术的发展导致肺部微小结节尤其是肺磨玻璃结节（ground-glass opacity, GGO）检出逐年增多，但术前定性困难。本研究探讨肺部微小结节的临床诊断及微创手术治疗的必要性和可行性、病理诊断，微创切除及淋巴结切除的手术方式。

方法

对2013年12月-2016年11月接受电视胸腔镜手术（video-assisted thoracic surgery, VATS）治疗并有明确病理诊断的共129例患者的临床资料回顾性分析。所有患者术前行薄层计算机断层扫描（computed tomography, CT）扫描，其中21个微小结节术前行CT引导下Hook-wire定位，并根据病理性质及患者身体状况采用不同手术方式。

结果

共129个微小结节，实性结节（solid pulmonary nodule, SPN）37个，恶性比例是24.3%（9/37），术后病理结果为：肺原发性鳞状细胞癌3个，浸润性腺癌（invasive adenocarcioma, IA）3个，转移癌2个，小细胞肺癌（small cell lung cancer, SCLC）1个，错构瘤16个，其他炎症等良性病变12个；49个混合性GGO（mixed ground-glass opacity, mGGO）的恶性比例是63.3%（31/49），术后病理结果为：IA 19个，微浸润腺癌（micro invasive adenocarcioma, MIA）6个，原位腺癌（adenocarcioma in situ, AIS）4个，非典型性腺瘤样增生（atipical adenomatous hyperplasia, AAH）1个，SCLC 1个，炎症等良性病变18个；43个纯GGO（pure ground-glass opacity, pGGO）的恶性比例是86.0%（37/43），术后病理结果为：AIS 19个，MIA 6个，IA 6个，AAH 6个，炎症等良性病变6个；GGO总的恶性比例是73.9%（68/92）。52个良性病变均采用VATS肺楔形切除；原发性非小细胞肺癌（non-small cell lung cancer, NSCLC）共73例，VATS肺叶切除和淋巴结清扫33例，VATS肺楔形切除和选择性淋巴结切除6例，VATS肺段切除和选择性淋巴结切除6例，VATS肺楔形切除28例；2个转移癌和2个SCLC，采用VATS肺楔形切除术。另有6例患者术中冰冻病理存在误差，其中2例选择二次手术行肺叶切除和淋巴结清扫。45例有淋巴结病理结果NSCLC只有两例以SPN为表现的IA出现纵隔淋巴结转移，其余均未出现淋巴结转移。术后随访1个月-35个月，平均（15.1±10.2）个月，无复发及转移。

结论

肺部微小结节尤其是GGO，是恶性病灶的概率大，应积极外科处理；围手术期应与患者及家属充分告知冰冻病理结果存在误差可能性，避免医疗纠纷。

Incidence of solitary pulmonary nodules in Northeastern France: a population-based study in five regions

Background

The discovery of a solitary pulmonary nodule (SPN) on a chest imaging exam is of major clinical concern. However, the incidence rates of SPNs in a general population have not been estimated. The objective of this study was to provide incidence estimates of SPNs in a general population in 5 northeastern regions of France.

Methods

This population-based study was undertaken in 5 regions of northeastern France in May 2002-March 2003 and May 2004-June 2005. SPNs were identified by chest CT reports collected from all radiology centres in the study area by trained readers using a standardised procedure. All reports for patients at least 18 years old, without a previous history of cancer and showing an SPN between 1 and 3 cm, were included.

Results

A total of 11,705 and 20,075 chest CT reports were collected for the 2002–2003 and 2004–2005 periods, respectively. Among them, 154 and 297 reports showing a SPN were included, respectively for each period. The age-standardised incidence rate (IR) was 10.2 per 100,000 person-years (95% confidence interval 8.5–11.9) for 2002–2003 and 12.6 (11.0–14.2) for 2004–2005. From 2002 to 2005, the age-standardised IR evolved for men from 16.4 (13.2–19.6) to 17.7 (15.0–20.4) and for women from 4.9 (3.2–6.6) to 8.2 (6.4–10.0). In multivariate Poisson regression analysis, gender, age, region and period were significantly associated with incidence variation.

Conclusions

This study provides reference incidence rates of SPN in France. Incidence was higher for men than women, increased with age for both gender and with time for women. Trends in smoking prevalence and improvement in radiological equipment may be related to incidence variations.

Prediction of lung cancer incidence on the low-dose computed tomography arm of the National Lung Screening Trial: A dynamic Bayesian network

INTRODUCTION

Identifying high-risk lung cancer individuals at an early disease stage is the most effective way of improving survival. The landmark National Lung Screening Trial (NLST) demonstrated the utility of low-dose computed tomography (LDCT) imaging to reduce mortality (relative to X-ray screening). As a result of the NLST and other studies, imaging-based lung cancer screening programs are now being implemented. However, LDCT interpretation results in a high number of false positives. A set of dynamic Bayesian networks (DBN) were designed and evaluated to provide insight into how longitudinal data can be used to help inform lung cancer screening decisions.

METHODS

The LDCT arm of the NLST dataset was used to build and explore five DBNs for high-risk individuals. Three of these DBNs were built using a backward construction process, and two using structure learning methods. All models employ demographics, smoking status, cancer history, family lung cancer history, exposure risk factors, comorbidities related to lung cancer, and LDCT screening outcome information. Given the uncertainty arising from lung cancer screening, a cancer state-space model based on lung cancer staging was utilized to characterize the cancer status of an individual over time. The models were evaluated on balanced training and test sets of cancer and non-cancer cases to deal with data imbalance and overfitting.

RESULTS

Results were comparable to expert decisions. The average area under the curve (AUC) of the receiver operating characteristic (ROC) for the three intervention points of the NLST trial was higher than 0.75 for all models. Evaluation of the models on the complete LDCT arm of the NLST dataset (N=25,486) demonstrated satisfactory generalization. Consensus of predictions over similar cases is reported in concordance statistics between the models' and the physicians' predictions. The models' predictive ability with respect to missing data was also evaluated with the sample of cases that missed the second screening exam of the trial (N=417). The DBNs outperformed comparison models such as logistic regression and naïve Bayes.

CONCLUSION

The lung cancer screening DBNs demonstrated high discrimination and predictive power with the majority of cancer and non-cancer cases.

Collateral findings during computed tomography scan for atrial fibrillation ablation: Let’s take a look around

The growing number of atrial fibrillation catheter ablation procedures warranted the development of advanced cardiac mapping techniques, such as image integration between electroanatomical map and cardiac computed tomography. While scanning the chest before catheter ablation, it is frequent to detect cardiac and extracardiac collateral findings. Most collateral findings are promptly recognized as benign and do not require further attention. However, sometimes clinically relevant collateral findings are detected, which often warrant extra diagnostic examinations or even invasive procedure, and sometimes need to be followed-up over time. Even though reporting and further investigating collateral findings has not shown a clear survival benefit, almost all the working groups providing data on collateral findings reported some collateral findings eventually coming out to be malignancies, sometimes at an early stage. Therefore, there is currently no clear agreement about the right strategy to be followed.

[Clinical Study of Surgical Treatment of Non-small Cell Lung Cancer 10 mm or Less in Diameter Under Video-assisted Thoracoscopy]

背景与目的

早期原发性非小细胞肺癌（non-small cell lung cancer, NSCLC）的手术切除及淋巴结切除的合理方式存在较大争议，本研究旨在探讨直径≤10 mm的原发NSCLC的微创切除及淋巴结切除的手术方式。

方法

对2013年7月-2016年3月在我院接受电视胸腔镜手术（video-assisted thoracic surgery, VATS）治疗并有明确病理诊断为NSCLC的共46例患者的临床资料进行回顾性分析。所有患者术前行薄层计算机断层扫描（computed tomography, CT），实性结节5例，混合性磨玻璃结节（mixed ground-glass opacity, mGGO）23例，纯磨玻璃结节（pure ground-glass opacity, pGGO）18例。根据患者具体情况采用不同术式，包括VATS肺叶切除和系统性淋巴结清扫，VATS肺楔形切除和选择性淋巴结切除，VATS肺段切除和选择性淋巴结切除，或仅采用VATS肺楔形切除。其中7例术前行CT引导下Hook-wire定位。

结果

VATS肺叶切除和系统性淋巴结清扫23例（mGGOs 15例，pGGOs 4例，实性结节4例），只有1例实性腺癌结节出现N2淋巴结转移，VATS肺楔形切除和选择性淋巴结切除5例（mGGOs 2例，pGGOs 3例）和VATS肺段切除和选择性淋巴结切除4例（mGGOs 2例，pGGOs 2例）均无淋巴结转移，仅采用VATS肺楔形切除14例（mGGOs 4例，pGGOs 9例，实性结节1例）。7例Hook-wire定位均成功。围手术期无重大并发症，随访1个月-26个月，平均（13.7±8.7）个月，无复发及转移。

结论

直径≤10 mm以mGGO和pGGO为表现的原发性NSCLC淋巴结转移率低，术中可以不进行淋巴结的清扫，实性结节应选择性淋巴结切除或系统性淋巴结清扫。高龄和心肺功能差的患者可以选择楔形切除或肺段切除。术前运用Hook-wire定位安全有效，可为VATS提供便利。

Significance of pulmonary nodules in multi-detector computed tomography scan of noncancerous patients

Background:

Computed tomography (CT) scan is one the most useful devices in chest imaging. CT scan can be used in mediastinal abnormality, lungs, and pleural evaluations. According to the high prevalence and different causes of pulmonary nodules, we designed this study to evaluate the prevalence and the types of pulmonary nodules in noncancerous patients who underwent chest multi-detector CT (MDCT) scan.

Materials and Methods:

This was a cross-sectional study which was in our hospital to evaluate the prevalence of pulmonary nodules in noncancerous patients who underwent MDCT. A checklist was used for data collection containing number, location, size, and shape of pulmonary nodules if present in CT scan, and we also included patient's age and history of smoking. We analyzed the data with Statistical Program for Social Sciences software (version 18).

Results:

In this study, 115 patients (40%) had a pulmonary nodule. The mean number of a total nodule in each patient was 0.8 ± 0.07. Mean number of intra-parenchymal, sub pleural, and perivascular nodules were 0.34 ± 0.04, 0.31 ± 0.04, and 0.14 ± 0.02, respectively. The mean number of calcified nodules was 0.13 ± 0.02. There was no significant correlation between age and nodule characteristics (P > 0.05).

Conclusion:

The prevalence of pulmonary nodules was quite frequent in MDCT scan of noncancerous cases. So, it should not be overvalued in noncancerous cases.

[Management of solid pulmonary nodules]

The increasing availability of computed tomography has meant that the number of incidentally detected solitary pulmonary nodules (SPN) has greatly increased in recent years. A reasonable management of these SPN is necessary in order to firstly be able to detect malignant lesions early on and secondly to avoid upsetting the patient unnecessarily or carrying out further stressful diagnostic procedures. This review article shows how the dignity of SPNs can be estimated and based on this how the management can be accomplished taking established guidelines into consideration.

Incidentally detected lung nodules: clinical predictors of adherence to Fleischner Society surveillance guidelines

OBJECTIVE

The objective of this study was to determine adherence to incidentally detected lung nodule computed tomographic (CT) surveillance recommendations and identify demographic and clinical factors that increase the likelihood of CT surveillance.

MATERIALS AND METHODS

A total of 419 patients with incidentally detected lung nodules were included. Recorded data included patient demographic, radiologic, and clinical characteristics and outcomes at a 4-year follow-up. Multivariate logistic regression models determined the factors associated with likelihood of recommended CT surveillance.

RESULTS

At least 1 recommended surveillance chest CT was performed on 48% of the patients (148/310). Computed tomographic result communication to the patient (odds ratio [OR], 2.2; P = 0.006; confidence interval [CI], 1.3-4.0) or to the referring physician (OR, 2.8; P = 0.001; CI, 1.7-4.5) and recommendation of a specific surveillance time interval (OR, 1.7; P = 0.023; CI, 1.08-2.72) increased the likelihood of surveillance. Other demographic, radiologic, and clinical factors did not influence surveillance.

CONCLUSIONS

Documented physician and patient result communication as well as the recommendation of a specific surveillance time interval increased the likelihood of CT surveillance of incidentally detected lung nodules.

A practical approach to radiological evaluation of CT lung cancer screening examinations

Lung cancer is the most common cause of cancer-related death in the world. The Dutch-Belgian Randomized Lung Cancer Screening Trial (Dutch acronym: NELSON) was launched to investigate whether screening for lung cancer by low-dose multidetector computed tomography (CT) in high-risk patients will lead to a decrease in lung cancer mortality. The NELSON lung nodule management is based on nodule volumetry and volume doubling time assessment. Evaluation of CT examinations in lung cancer screening can also include assessment of coronary calcification, emphysema and airway wall thickness, biomarkers for major diseases that share risk factors with lung cancer. In this review, a practical approach to the radiological evaluation of CT lung cancer screening examinations is described.

[Diagnosis and management of solitary pulmonary nodules]

目前，肺癌已跃居成为我国发病率及死亡率最高的恶性肿瘤，总体5年生存率较低；早诊早治是提高肺癌患者生存率及改善预后的关键，而早期肺癌患者常无任何症状和体征，只在影像学上表现为肺孤立性结节病变。提高对孤立性肺结节良恶性的鉴别诊断能力是临床诊治过程中的难点与热点。随着各种诊治技术的发展，孤立性肺结节病变性质的诊断准确率已大大提高。

Prevalence and clinical significance of collateral findings detected by chest computed tomography in patients undergoing atrial fibrillation ablation

AIMS

Chest computed tomography (CT) scanning is increasingly used as an imaging technique in patients undergoing atrial fibrillation (AF) catheter ablation. Chest CT scans visualize organs other than the heart and collateral findings may be identified incidentally. Our study aims to assess the prevalence and clinical relevance of such collateral findings in patients undergoing AF ablation.

METHODS AND RESULTS

One hundred and seventy-three patients (127 males, age 59 ± 10 years) underwent chest CT scan for image integration in AF ablation. Collateral findings from visualized thoracic and upper abdominal organs were collected. Findings that required further investigations or treatment according to current guidelines were considered as clinically significant. A total of 164 collateral findings were identified in 97 (56%) patients, and most patients showed abnormalities of the lungs (67 patients, 39%). Forty-nine (28%) patients had clinically significant findings needing further investigation and 17 (10%) of them required specific treatments, including three cases (1.7 %) of lung malignancy.

CONCLUSIONS

Chest CT images acquired for integration in AF ablation should be read thoroughly as they may serve as a screening tool for otherwise unrecognized clinically significant conditions of the heart, lungs, or other visualized organs.

[Characterization and management of incidentally detected solitary pulmonary nodules]

How to deal with solitary pulmonary nodules (SPN) which are incidentally detected by computed tomography (CT) is an increasingly important task in the era of modern multislice CT. This paper reviews the morphological and functional characteristics and their value for discrimination between benign and malignant SPNs. In particular, the importance of nodule size, growth rate, margin morphology, density, calcifications or fatty components within the nodules, the significance of cavitations or aerobronchograms, enhancement patterns at dynamic contrast-enhanced CT and findings on positron emission tomography (PET) are discussed. The Bayesian analysis to calculate the probability of malignancy is presented. Finally, flow charts demonstrate the national and international recommendations for nodule management.

Incidentally detected small pulmonary nodules on CT

The widespread use of multidetector computed tomography for imaging of the chest has lead to a significant increase in the number of incidentally detected pulmonary nodules. The significance of these nodules is often uncertain and further investigations may be required. This article will review the spectrum of imaging appearances of small pulmonary nodules, and highlight the few features that allow confident characterization of a nodule as benign or malignant; current guidelines for the management of incidentally detected nodules will also be discussed.

Multilevel binomial logistic prediction model for malignant pulmonary nodules based on texture features of CT image

PURPOSE

To introduce multilevel binomial logistic prediction model-based computer-aided diagnostic (CAD) method of small solitary pulmonary nodules (SPNs) diagnosis by combining patient and image characteristics by textural features of CT image.

MATERIALS AND METHODS

Describe fourteen gray level co-occurrence matrix textural features obtained from 2171 benign and malignant small solitary pulmonary nodules, which belongs to 185 patients. Multilevel binomial logistic model is applied to gain these initial insights.

RESULTS

Five texture features, including Inertia, Entropy, Correlation, Difference-mean, Sum-Entropy, and age of patients own aggregating character on patient-level, which are statistically different (P<0.05) between benign and malignant small solitary pulmonary nodules.

CONCLUSION

Some gray level co-occurrence matrix textural features are efficiently descriptive features of CT image of small solitary pulmonary nodules, which can profit diagnosis of earlier period lung cancer if combined patient-level characteristics to some extent.

Diagnosis and management of solitary pulmonary nodules

The advent of computed tomography (CT) screening with or without the help of computer-aided detection systems has increased the detection rate of solitary pulmonary nodules (SPNs), including that of early peripheral lung cancer. Helical dynamic (HD)CT, providing the information on morphologic and hemodynamic characteristics with high specificity and reasonably high accuracy, can be used for the initial assessment of SPNs. (18)F-fluorodeoxyglucose PET/CT is more sensitive at detecting malignancy than HDCT. Therefore, PET/CT may be selectively performed to characterize SPNs when HDCT gives an inconclusive diagnosis. Serial volume measurements are currently the most reliable methods for the tissue characterization of subcentimeter nodules. When malignant nodule is highly suspected for subcentimeter nodules, video-assisted thoracoscopic surgery nodule removal after nodule localization using the pulmonary nodule-marker system may be performed for diagnosis and treatment.