Utility of abbreviated MRI in the post-treatment evaluation of rectal cancer.

BACKGROUND: Post-treatment evaluation of patients with rectal cancer (RC) using magnetic resonance imaging (MRI) burdens medical resources, necessitating an exploration of abbreviated protocols. PURPOSE: To evaluate the diagnostic performance of abbreviated MRI (A-MRI) for the post-treatment evaluation of RC patients. MATERIAL AND METHODS: This retrospective study included RC patients who underwent non-contrast rectal MRI and standard liver MRI, as well as abdominal contrast-enhanced computed tomography (CECT) for post-treatment evaluation. A-MRI comprised diffusion-weighted imaging (DWI) and T2-weighted imaging of the upper abdomen and the pelvic cavity. Three radiologists independently reviewed A-MRI, CECT, and standard liver MRI in the detection of viable disease. The diagnostic performances were compared using a reference standard considering all available information, including pathology, FDG-PET, endoscopic results, and clinical follow-up. RESULTS: We included 78 patients (50 men, 28 women; mean age=60.9 ± 10.2 years) and observed viable disease in 34 (43.6%). On a per-patient-basis analysis, A-MRI showed significantly higher sensitivity (95% vs. 81%, P = 0.04) and higher accuracy (93% vs. 82%, P < 0.01), compared to those of CECT, while A-MRI showed comparable sensitivity (91% vs. 91%, P = 0.42) and accuracy (97% vs. 98%, P = 0.06) to that of standard liver MRI. On a per-lesion-based analysis, A-MRI exhibited significantly superior lesion detectability than that of CECT (figure of merit 0.91 vs. 0.77, P < 0.01) and comparable to that of standard liver MRI (figure of merit 0.91 vs. 0.92, P = 0.75). CONCLUSION: A-MRI exhibited higher sensitivity and diagnostic accuracy than those of CECT in the post-treatment evaluation of RC, while it showed comparable performances with standard liver MRI. A-MRI provides diagnostic added value in the follow-up of RC patients.

Diagnostic performance and image quality of an image-based denoising algorithm applied to radiation dose-reduced CT in diagnosing acute appendicitis.

PURPOSE: To evaluate diagnostic performance and image quality of ultralow-dose CT (ULDCT) in diagnosing acute appendicitis with an image-based deep-learning denoising algorithm (IDLDA). METHODS: This retrospective multicenter study included 180 patients (mean ± standard deviation, 29 ± 9 years; 91 female) who underwent contrast-enhanced 2-mSv CT for suspected appendicitis from February 2014 to August 2016. We simulated ULDCT from 2-mSv CT, reducing the dose by at least 50%. Then we applied an IDLDA on ULDCT to produce denoised ULDCT (D-ULDCT). Six radiologists with different experience levels (three board-certified radiologists and three residents) independently reviewed the ULDCT and D-ULDCT. They rated the likelihood of appendicitis and subjective image qualities (subjective image noise, diagnostic acceptability, and artificial sensation). One radiologist measured image noise, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR). We used the receiver operating characteristic (ROC) analyses, Wilcoxon's signed-rank tests, and paired t-tests. RESULTS: The area under the ROC curves (AUC) for diagnosing appendicitis ranged 0.90-0.97 for ULDCT and 0.94-0.97 for D-ULDCT. The AUCs of two residents were significantly higher on D-ULDCT (AUC difference = 0.06 [95% confidence interval, 0.01-0.11; p = .022] and 0.05 [0.00-0.10; p = .046], respectively). D-ULDCT provided better subjective image noise and diagnostic acceptability to all six readers. However, the response of board-certified radiologists and residents differed in artificial sensation (all p ≤ .003). D-ULDCT showed significantly lower image noise, higher SNR, and higher CNR (all p < .001). CONCLUSION: An IDLDA can provide better ULDCT image quality and enhance diagnostic performance for less-experienced radiologists.

Risk of hematologic malignant neoplasms from head CT radiation in children and adolescents presenting with minor head trauma: a nationwide population-based cohort study.

OBJECTIVES: The carcinogenic risks of CT radiation in children and adolescents remain debated. We aimed to assess the carcinogenic risk of CTs performed in children and adolescents with minor head trauma. METHODS: In this nationwide population-based cohort study, we included 2,411,715 patients of age 0-19 with minor head trauma from 2009 to 2017. We excluded patients with elevated cancer risks or substantial past medical radiation exposure. Patients were categorized into CT-exposed or CT-unexposed group according to claim codes for head CT. The primary outcome was development of hematologic malignant neoplasms. Secondary outcomes included development of malignant solid neoplasms and benign neoplasms in the brain. We measured the incidence rate ratio (IRR) and incidence rate difference (IRD) using G-computation with Poisson regression adjusting for age, sex, hospital setting, and the type of head trauma. RESULTS: Hematologic malignant neoplasms developed in 100 of 216,826 patients during 1,303,680 person-years in the CT-exposed group and in 808 of 2,194,889 patients during 13,501,227 person-years in the CT-unexposed group. For hematologic malignant neoplasms, the IRR was 1.29 (95% CI, 1.03-1.60) and the IRD was 1.71 (95% CI, 0.04-3.37) per 100,000 person-years at risk. The majority of excess hematologic malignant neoplasms were leukemia (IRR, 1.40 [98.3% CI, 1.05-1.87]; IRD, 1.59 [98.3% CI, 0.02-3.16] per 100,000 person-years at risk). There were no between-group differences for secondary outcomes. CONCLUSIONS: Radiation exposure from head CTs in children and adolescents with minor head trauma was associated with an increased incidence of hematologic malignant neoplasms. CLINICAL RELEVANCE STATEMENT: Our study provides a quantitative grasp of the risk conferred by CT examinations in children and adolescents, thereby providing the basis for cost-benefit analyses and evidence-driven guidelines for patient triaging in head trauma. KEY POINTS: • This nationwide population-based cohort study showed that radiation exposure from head CTs in children and adolescents was associated with a higher incidence of hematologic malignant neoplasms. • The incidence rate of hematologic malignant neoplasms in the CT-exposed group was 29% higher than that in the CT-unexposed group (IRR, 1.29 [95% CI, 1.03-1.60]), and there were approximately 1.7 excess neoplasms per 100,000 person-years at risk in the CT-exposed group (IRD, 1.71 [0.04-3.37]). • Our study provides a quantified grasp of the risk conferred by CT examinations in children and adolescents, while controlling for biases observed in previous studies via specifying CT indication and excluding patients with predisposing conditions for cancer development.

Improving radiomics reproducibility using deep learning-based image conversion of CT reconstruction algorithms in hepatocellular carcinoma patients.

OBJECTIVES: CT reconstruction algorithms affect radiomics reproducibility. In this study, we evaluate the effect of deep learning-based image conversion on CT reconstruction algorithms. METHODS: This study included 78 hepatocellular carcinoma (HCC) patients who underwent four-phase liver CTs comprising non-contrast, late arterial (LAP), portal venous (PVP), and delayed phase (DP), reconstructed using both filtered back projection (FBP) and advanced modeled iterative reconstruction (ADMIRE). PVP images were used to train a convolutional neural network (CNN) model to convert images from FBP to ADMIRE and vice versa. LAP, PVP, and DP images were used for validation and testing. Radiomic features were extracted for each patient with a semi-automatic segmentation tool. We used concordance correlation coefficients (CCCs) to evaluate the radiomics reproducibility for original FBP (oFBP) vs. original ADMIRE (oADMIRE), oFBP vs. converted FBP (cFBP), and oADMIRE vs. converted ADMIRE (cADMIRE). RESULTS: In the test group including 30 patients, the CCC and proportion of reproducible features (CCC ≥ 0.85) for oFBP vs. oADMIRE were 0.65 and 32.9% (524/1595) for LAP, 0.65 and 35.9% (573/1595) for PVP, and 0.69 and 43.8% (699/1595) for DP. For oFBP vs. cFBP, the values increased to 0.92 and 83.9% (1339/1595) for LAP, 0.89 and 71.0% (1133/1595) for PVP, and 0.90 and 79.7% (1271/1595) for DP. Similarly, for oADMIRE vs. cADMIRE, the values increased to 0.87 and 68.1% (1086/1595) for LAP, 0.91 and 82.1% (1309/1595) for PVP, and 0.89 and 76.2% (1216/1595) for DP. CONCLUSIONS: CNN-based image conversion between CT reconstruction algorithms improved the radiomics reproducibility of HCCs. CLINICAL RELEVANCE STATEMENT: This study demonstrates that using a CNN-based image conversion technique significantly improves the reproducibility of radiomic features in HCCs, highlighting its potential for enhancing radiomics research in HCC patients. KEY POINTS: Radiomics reproducibility of HCC was improved via CNN-based image conversion between two different CT reconstruction algorithms. This is the first clinical study to demonstrate improvements across a range of radiomic features in HCC patients. This study promotes the reproducibility and generalizability of different CT reconstruction algorithms in radiomics research.

A rabbit model for embolic infarct potentials of injectables using ultrasound-guided carotid artery puncture.

In order to evaluate the in vivo thrombogenicity of injectable agents, a suitable animal model is needed. We introduce an ultrasound-guided non-selective cerebral artery occlusion model via the common carotid arteries of rabbits. A total of 30 rabbits were assigned to an experimental group (n = 20) and a control group (n = 10). Each group received 2 mL suspension of embolic agent or 2 mL of normal saline, respectively, under ultrasound guidance. The animals were observed for immediate reaction and underwent magnetic resonance imaging (MRI) scan. Follow-up neurologic examination was conducted 24 h following the procedure. In 7 of the 30 rabbits, 2 in the control group and 5 in the experimental group, the administration of either normal saline or the embolic agent failed. Among the successfully injected 15 experimental animals, 14 showed neurologic impairment or deceased, whereas 1 animal did not show significant neurologic deficit. The MRI of 4 experimental animals showed detectable cerebral infarction on diffusion-weighted imaging. None of the 8 control animals showed neurologic abnormality and their brain MRI was normal. Our minimally invasive model is technically feasible and competent to show thrombogenecity of an injectable agent and consequent in vivo neurologic outcome.

Extramural venous invasion and depth of extramural invasion on preoperative CT as prognostic imaging biomarkers in patients with locally advanced ascending colon cancer.

PURPOSE: This study evaluates the prognostic significance of EMVI and DEMI on preoperative CT in patients with ascending colon cancer. METHODS: This retrospective study included consecutive patients with T3 ascending colon cancer from January 2012 to December 2016 in a tertiary center. Two radiologists independently reviewed EMVI, DEMI, and nodal status on preoperative CT. We assessed the association of age, sex, mucinous adenocarcinoma, EMVI, and DEMI with metastasis on preoperative CT using univariable and multivariable analysis. We also compared disease-free survival (DFS) with and without variables (age, sex, mucinous adenocarcinoma, EMVI, DEMI and adjuvant chemotherapy) using Cox's proportional hazards models. We assessed interobserver agreements on imaging features using the Cohen's weighted kappa. RESULTS: Of 237 patients [107 men; mean (standard deviation) age, 66 (13) years], 24 had metastases on preoperative CT. Positive EMVI was associated with metastasis (odds ratio 16.9; P < 0.001) on multivariable analysis. Of 194 patients [83 men; 65 (13) years] included for DFS analysis, recurrence was observed in 31 (16%) with median follow-up of 53 months. Positive EMVI [hazard ratio (HR) 4.8; P < 0.001] and DEMI > 5 mm (HR 5.5; P < 0.001) were associated with worse DFS. Interobserver agreements were good (kappa = 0.64-0.67). CONCLUSION: Positive EMVI and DEMI > 5 mm on preoperative CT were associated with a worse T3 ascending colon cancer prognosis. Thus, these CT findings could be used as imaging biomarkers for T3 ascending colon cancer risk stratification.

Incidence of malignancy in adrenal nodules detected on staging CTs of patients with potentially resectable colorectal cancer.

OBJECTIVE: To measure the prevalence of adrenal nodules detected on staging CT in patients with resectable colorectal cancer, and the proportion of patients with malignant nodules among them. METHODS: This retrospective study included 6474 patients (median age, 65; interquartile range, 56-73; 3902 men) who underwent staging CT for colorectal cancer between May 2003 and December 2018. The patients had potentially resectable colorectal cancer, including resectable hepatic or pulmonary metastases. Through retrospective CT image review, patients with adrenal nodules were identified for the prevalence of adrenal nodule. Among patients with adrenal nodules, per-patient proportions of malignant nodules, adrenal metastasis from colorectal cancer, and additional adrenal examinations (biopsy or imaging tests) were measured. A secondary analysis was performed using data from the official CT reports. RESULTS: The prevalence of adrenal nodules was 5.6% (363 of 6474; 95% CI: 5.1, 6.2). The proportions of malignant nodules and adrenal metastasis from colorectal cancer were 0.8% (3 of 363; 0.2, 2.4) and 0.3% (1 of 363; 0.0, 1.5), respectively. 6.1% (22 of 363; 3.8, 9.0) of the patients underwent additional adrenal examination. According to official CT reports, the prevalence of adrenal nodules and proportions of malignant nodules, adrenal metastasis from colorectal cancer, and additional adrenal examination were 1.9% (125 of 6474; 1.6, 2.3), 1.6% (2 of 125; 0.2, 5.7), 0% (0 of 125; 0.0, 2.9), and 10.4% (1 of 125; 5.7, 17.1), respectively. CONCLUSION: Adrenal nodules detected in staging CTs in patients with otherwise resectable colorectal cancers are rarely malignant. KEY POINTS: • Among 6474 patients who underwent staging CT and had potentially resectable colorectal cancer, 363 had adrenal nodules (≥ 10 mm) detected in retrospective CT image review. • Three out of the 363 patients with adrenal nodules detected on staging CT had malignant adrenal nodules, one of whom had metastasis from colorectal cancer.

Appendiceal Visualization on 2-mSv CT vs. Conventional-Dose CT in Adolescents and Young Adults with Suspected Appendicitis: An Analysis of Large Pragmatic Randomized Trial Data.

OBJECTIVE: We compared appendiceal visualization on 2-mSv CT vs. conventional-dose CT (median 7 mSv) in adolescents and young adults and analyzed the undesirable clinical and diagnostic outcomes that followed appendiceal nonvisualization. MATERIALS AND METHODS: A total of 3074 patients aged 15-44 years (mean ± standard deviation, 28 ± 9 years; 1672 female) from 20 hospitals were randomized to the 2-mSv CT or conventional-dose CT group (1535 vs. 1539) from December 2013 through August 2016. A total of 161 radiologists from 20 institutions prospectively rated appendiceal visualization (grade 0, not identified; grade 1, unsure or partly visualized; and grade 2, clearly and entirely visualized) and the presence of appendicitis in these patients. The final diagnosis was based on CT imaging and surgical, pathologic, and clinical findings. We analyzed undesirable clinical or diagnostic outcomes, such as negative appendectomy, perforated appendicitis, more extensive than simple appendectomy, delay in patient management, or incorrect CT diagnosis, which followed appendiceal nonvisualization (defined as grade 0 or 1) and compared the outcomes between the two groups. RESULTS: In the 2-mSv CT and conventional-dose CT groups, appendiceal visualization was rated as grade 0 in 41 (2.7%) and 18 (1.2%) patients, respectively; grade 1 in 181 (11.8%) and 81 (5.3%) patients, respectively; and grade 2 in 1304 (85.0%) and 1421 (92.3%) patients, respectively (p < 0.001). Overall, undesirable outcomes were rare in both groups. Compared to the conventional-dose CT group, the 2-mSv CT group had slightly higher rates of perforated appendicitis (1.1% [17] vs. 0.5% [7], p = 0.06) and false-negative diagnoses (0.4% [6] vs. 0.0% [0], p = 0.01) following appendiceal nonvisualization. Otherwise, these two groups were comparable. CONCLUSION: The use of 2-mSv CT instead of conventional-dose CT impairs appendiceal visualization in more patients. However, appendiceal nonvisualization on 2-mSv CT rarely leads to undesirable clinical or diagnostic outcomes.

Tumor resectability and response on CT following neoadjuvant therapy for pancreatic cancer: inter-observer agreement study.

OBJECTIVES: First, to measure inter-observer agreement regarding tumor resectability and response, and second, to measure diagnostic performance in predicting negative resection margin, on re-staging CTs of patients who received neoadjuvant therapy for pancreatic cancer. METHODS: This retrospective study included patients who received neoadjuvant therapy for borderline resectable pancreatic cancer from 2017 to 2020. Six readers independently evaluated initial staging and re-staging CT images. They categorized the resectability on re-staging CT based on the NCCN guideline, and evaluated tumor response to neoadjuvant therapy according to our proposed criteria on a 5-grade scale. For inter-observer agreement, Gwet's agreement coefficients were used. A crossed random effect model was used to pool the sensitivity and specificity of six readers in predicting negative resection margin. RESULTS: Seventy-seven patients with the median age of 66 (59-70) were included. The pooled agreement for tumor resectability was 0.64 (95% CI, 0.56-0.71) for differentiating the three categories, and 0.84 (0.77-0.91) for differentiating resectable or borderline resectable cancer vs. unresectable cancer. Agreement for tumor response grade was 0.89 (0.85-0.92). The pooled sensitivity and specificity for predicting negative resection margin were 48% (43-52%) and 61% (57-64%), respectively, when only "resectable" on re-staging CT was considered as index test positive. When either "resectable"' or "borderline resectable" was considered as positive, the pooled sensitivity and specificity were 91% (89-94%) and 5% (4-6%), respectively. CONCLUSION: CT can be used reliably with a high inter-observer agreement in selecting candidates for surgery after neoadjuvant therapy of pancreatic cancer. KEY POINTS: • On CT following neoadjuvant therapy of pancreatic cancer, six readers showed high agreement in differentiating resectable or borderline resectable vs. unresectable cancer (Gwet's coefficient, 0.84). • Inter-observer agreement was also high for our proposed tumor response grade (Gwet's coefficient, 0.89). • Specificity was very low (5%) while sensitivity was high (91%) when either resectable or borderline resectable cancer on re-staging CT was considered as predictive of negative resection margin status.

Adrenal Nodules Detected at Staging CT in Patients with Resectable Gastric Cancers Have a Low Incidence of Malignancy.

Background Guidelines recommending additional imaging for adrenal nodules lack relevant epidemiologic evidence. Purpose To measure the prevalence of adrenal nodules detected at staging CT in patients with potentially resectable gastric cancer and the proportion of patients with malignant nodules among them. Materials and Methods This retrospective study included 10 250 consecutive patients (median age, 63 years; interquartile range, 53-71 years; 6884 men) who underwent staging CT and had potentially resectable gastric cancer in a tertiary center (May 2003 to December 2018). All 10 250 CT studies were retrospectively reviewed, and patients with adrenal nodules (or thickening ≥10 mm) were identified to measure the prevalence of adrenal nodules. Among patients with adrenal nodules, the per-patient proportions of malignant nodules, adrenal metastasis from gastric cancer, and additional adrenal examinations were measured. A secondary analysis was performed by using data from the original CT reports. The same metrics that were used in the retrospective review were assessed. Results The prevalence of adrenal nodules was 4.5% (95% CI: 4.1, 4.9; 462 of 10 250). The proportions of malignant nodules and adrenal metastasis from gastric cancer were 0.4% ( 95% CI: 0.1, 1.6; two of 462) and 0% (95% CI: 0.0, 0.8; 0 of 462), respectively. A total of 27% of the patients (95% CI: 23, 31; 123 of 462) underwent additional adrenal examination. According to original CT reports, the prevalence of adrenal nodules and the proportions of malignant nodules, adrenal metastases from gastric cancer, and additional adrenal examination were 2.7% (95% CI: 2.4, 3.0; 272 of 10 250), 0.7% (95% CI: 0.1, 2.6; two of 272), 0% (95% CI: 0.0, 1.4; 0 of 272), and 42.6% (95% CI: 36.7, 48.8; 116 of 272), respectively. Conclusion Although adrenal nodules were detected frequently on staging CT images of patients with otherwise resectable gastric cancer, these nodules were rarely malignant. ©RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Baumgarten in this issue.

Deep Learning-Based Computer-Aided Detection System for Automated Treatment Response Assessment of Brain Metastases on 3D MRI.

BACKGROUND: Although accurate treatment response assessment for brain metastases (BMs) is crucial, it is highly labor intensive. This retrospective study aimed to develop a computer-aided detection (CAD) system for automated BM detection and treatment response evaluation using deep learning. METHODS: We included 214 consecutive MRI examinations of 147 patients with BM obtained between January 2015 and August 2016. These were divided into the training (174 MR images from 127 patients) and test datasets according to temporal separation (temporal test set #1; 40 MR images from 20 patients). For external validation, 24 patients with BM and 11 patients without BM from other institutions were included (geographic test set). In addition, we included 12 MRIs from BM patients obtained between August 2017 and March 2020 (temporal test set #2). Detection sensitivity, dice similarity coefficient (DSC) for segmentation, and agreements in one-dimensional and volumetric Response Assessment in Neuro-Oncology Brain Metastases (RANO-BM) criteria between CAD and radiologists were assessed. RESULTS: In the temporal test set #1, the sensitivity was 75.1% (95% confidence interval [CI]: 69.6%, 79.9%), mean DSC was 0.69 ± 0.22, and false-positive (FP) rate per scan was 0.8 for BM ≥ 5 mm. Agreements in the RANO-BM criteria were moderate (κ, 0.52) and substantial (κ, 0.68) for one-dimensional and volumetric, respectively. In the geographic test set, sensitivity was 87.7% (95% CI: 77.2%, 94.5%), mean DSC was 0.68 ± 0.20, and FP rate per scan was 1.9 for BM ≥ 5 mm. In the temporal test set #2, sensitivity was 94.7% (95% CI: 74.0%, 99.9%), mean DSC was 0.82 ± 0.20, and FP per scan was 0.5 (6/12) for BM ≥ 5 mm. CONCLUSIONS: Our CAD showed potential for automated treatment response assessment of BM ≥ 5 mm.

The feasibility of deep learning-based synthetic contrast-enhanced CT from nonenhanced CT in emergency department patients with acute abdominal pain.

Our objective was to investigate the feasibility of deep learning-based synthetic contrast-enhanced CT (DL-SCE-CT) from nonenhanced CT (NECT) in patients who visited the emergency department (ED) with acute abdominal pain (AAP). We trained an algorithm generating DL-SCE-CT using NECT with paired precontrast/postcontrast images. For clinical application, 353 patients from three institutions who visited the ED with AAP were included. Six reviewers (experienced radiologists, ER1-3; training radiologists, TR1-3) made diagnostic and disposition decisions using NECT alone and then with NECT and DL-SCE-CT together. The radiologists' confidence in decisions was graded using a 5-point scale. The diagnostic accuracy using DL-SCE-CT improved in three radiologists (50%, P = 0.023, 0.012, < 0.001, especially in 2/3 of TRs). The confidence of diagnosis and disposition improved significantly in five radiologists (83.3%, P < 0.001). Particularly, in subgroups with underlying malignancy and miscellaneous medical conditions (MMCs) and in CT-negative cases, more radiologists reported increased confidence in diagnosis (83.3% [5/6], 100.0% [6/6], and 83.3% [5/6], respectively) and disposition (66.7% [4/6], 83.3% [5/6] and 100% [6/6], respectively). In conclusion, DL-SCE-CT enhances the accuracy and confidence of diagnosis and disposition regarding patients with AAP in the ED, especially for less experienced radiologists, in CT-negative cases, and in certain disease subgroups with underlying malignancy and MMCs.

Diagnostic accuracy and complication rate of image-guided percutaneous transthoracic needle lung biopsy for subsolid pulmonary nodules: a systematic review and meta-analysis.

OBJECTIVES: To determine the diagnostic accuracy and complication rate of percutaneous transthoracic needle biopsy (PTNB) for subsolid pulmonary nodules and sources of heterogeneity among reported results. METHODS: We searched PubMed, EMBASE, and Cochrane libraries (until November 7, 2020) for studies measuring the diagnostic accuracy of PTNB for subsolid pulmonary nodules. Pooled sensitivity and specificity of PTNB were calculated using a bivariate random-effects model. Bivariate meta-regression analyses were performed to identify sources of heterogeneity. Pooled overall and major complication rates were calculated. RESULTS: We included 744 biopsies from 685 patients (12 studies). The pooled sensitivity and specificity of PTNB for subsolid nodules were 90% (95% confidence interval [CI]: 85-94%) and 99% (95% CI: 92-100%), respectively. Mean age above 65 years was the only covariate significantly associated with higher sensitivity (93% vs 85%, p = 0.04). Core needle biopsy showed marginally higher sensitivity than fine-needle aspiration (93% vs 83%, p = 0.07). Pooled overall and major complication rate of PTNB were 43% (95% CI: 25-62%) and 0.1% (95% CI: 0-0.4%), respectively. Major complication rate was not different between fine-needle aspiration and core needle biopsy groups (p = 0.25). CONCLUSION: PTNB had acceptable performance and a low major complication rate in diagnosing subsolid pulmonary nodules. The only significant source of heterogeneity in reported sensitivities was a mean age above 65 years. ADVANCES IN KNOWLEDGE: This is the first meta-analysis attempting to systemically determine the cause of heterogeneity in the diagnostic accuracy and complication rate of PTNB for subsolid pulmonary nodules.

MRI Texture Analysis for the Prediction of Stereotactic Radiosurgery Outcomes in Brain Metastases from Lung Cancer.

This study aims to evaluate the utility of texture analysis in predicting the outcome of stereotactic radiosurgery (SRS) for brain metastases from lung cancer. From 83 patients with lung cancer who underwent SRS for brain metastasis, a total of 118 metastatic lesions were included. Two neuroradiologists independently performed magnetic resonance imaging (MRI)-based texture analysis using the Imaging Biomarker Explorer software. Inter-reader reliability as well as univariable and multivariable analyses were performed for texture features and clinical parameters to determine independent predictors for local progression-free survival (PFS) and overall survival (OS). Furthermore, Harrell's concordance index (C-index) was used to assess the performance of the independent texture features. The primary tumor histology of small cell lung cancer (SCLC) was the only clinical parameter significantly associated with local PFS in multivariable analysis. Run-length non-uniformity (RLN) and short-run emphasis were the independent texture features associated with local PFS. In the non-SCLC (NSCLC) subgroup analysis, RLN and local range mean were associated with local PFS. The C-index of independent texture features was 0.79 for the all-patients group and 0.73 for the NSCLC subgroup. In conclusion, texture analysis on pre-treatment MRI of lung cancer patients with brain metastases may have a role in predicting SRS response.

Incidence Lung Cancer after a Negative CT Screening in the National Lung Screening Trial: Deep Learning-Based Detection of Missed Lung Cancers.

We aimed to analyse the CT examinations of the previous screening round (CTprev) in NLST participants with incidence lung cancer and evaluate the value of DL-CAD in detection of missed lung cancers. Thoracic radiologists reviewed CTprev in participants with incidence lung cancer, and a DL-CAD analysed CTprev according to NLST criteria and the lung CT screening reporting & data system (Lung-RADS) classification. We calculated patient-wise and lesion-wise sensitivities of the DL-CAD in detection of missed lung cancers. As per the NLST criteria, 88% (100/113) of CTprev were positive and 74 of them had missed lung cancers. The DL-CAD reported 98% (98/100) of the positive screens as positive and detected 95% (70/74) of the missed lung cancers. As per the Lung-RADS classification, 82% (93/113) of CTprev were positive and 60 of them had missed lung cancers. The DL-CAD reported 97% (90/93) of the positive screens as positive and detected 98% (59/60) of the missed lung cancers. The DL-CAD made false positive calls in 10.3% (27/263) of controls, with 0.16 false positive nodules per scan (41/263). In conclusion, the majority of CTprev in participants with incidence lung cancers had missed lung cancers, and the DL-CAD detected them with high sensitivity and a limited false positive rate.

Comparison of core needle biopsy and fine-needle aspiration in diagnosis of ma lignant salivary gland neoplasm: Systematic review and meta-analysis.

BACKGROUND: In this meta-analysis, we compared the risk of obtaining nondiagnostic results and the diagnostic accuracy for detection of salivary gland malignancy between core needle biopsy (CNB) and fine-needle aspiration (FNA). METHODS: All published English-language studies comparing CNB and FNA diagnostic accuracy for salivary gland masses through December 2019 were searched. Pooled risk ratios (RRs) of nondiagnostic results, sensitivities, and specificities of CNB and FNA for salivary gland malignancy diagnosis were determined. Complication rates were compared. RESULTS: Six studies (1924 procedures) were quantitatively analyzed. CNB yielded significantly fewer nondiagnostic results (P < .001) and had significantly higher pooled sensitivity (P < .001) and specificity (P = .002) than FNA for differentiating malignant and benign salivary gland neoplasms. Hematoma occurred in 0.3% of CNB, while no complication occurred in FNA procedures. CONCLUSION: CNB yielded fewer nondiagnostic results and had superior diagnostic performance compared with FNA for detecting salivary gland malignancies.

Biparametric versus multiparametric magnetic resonance imaging of the prostate: detection of clinically significant cancer in a perfect match group.

BACKGROUND: Biparametric (bp) magnetic resonance imaging (MRI) could be an alternative MRI for the detection of the clinically significant prostate cancer (csPCa). PURPOSE: To compare the accuracies of prostate cancer detection and localization between prebiopsy bpMRI and postbiopsy multiparametric MRI (mpMRI) taken on different days, using radical prostatectomy specimens as the reference standards. MATERIAL AND METHODS: Data of 41 total consecutive patients who underwent the following examinations and procedures between September 2015 and March 2017 were collected: (1) magnetic resonance- and/or ultrasonography-guided biopsy after bpMRI; (2) postbiopsy mpMRI; and (3) radical prostatectomy with csPCa. Two radiologists scored suspected lesions on bpMRI and mpMRI independently using Prostate Imaging Reporting and Data System version 2. The diagnostic accuracy of detecting csPCa and the Dice similarity coefficient were obtained. Apparent diffusion coefficient (ADC) ratios were also obtained for quantitative comparison between bpMRI and mpMRI. RESULTS: Diagnostic accuracies on bpMRI and mpMRI were 0.83 and 0.82 for reader 1; 0.80 and 0.82 for reader 2. There are no significantly different values of diagnostic sensitivities or specificities between the readers or between MRI protocols. Intra-observer Dice similarity coefficient was significantly lower in reader 2, compared to that in reader 1 between the two MRI protocols. The range of mean ADC ratio was 0.281-0.635. There was no statistically significant difference in the ADC ratio between bpMRI and mpMRI. CONCLUSIONS: Diagnostic performance of bpMRI without dynamic contrast enhancement MRI is not significantly different from mpMRI with dynamic contrast enhancement MRI in the detection of csPCa.