Artificial intelligence assistance for women who had spot compression view: reducing recall rates for digital mammography

Background

Mammography yields inevitable recall for indeterminate findings that need to be confirmed with additional views.

Purpose

To explore whether the artificial intelligence (AI) algorithm for mammography can reduce false-positive recall in patients who undergo the spot compression view.

Material and Methods

From January to December 2017, 236 breasts from 225 women who underwent the spot compression view due to focal asymmetry, mass, or architectural distortion on standard digital mammography were included. Three readers who were blinded to the study purpose, patient information, previous mammograms, following spot compression views, and any clinical or pathologic reports retrospectively reviewed 236 standard mammograms and determined the necessity of patient recall and the probability of malignancy per breast, first without and then with AI assistance. The performances of AI and the readers were evaluated with the recall rate, area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and accuracy.

Results

Among 236 examinations, 8 (3.4%) were cancers and 228 (96.6%) were benign. The recall rates of all three readers significantly decreased with AI assistance ( P < 0.05). The reader-averaged recall rates significantly decreased with AI assistance regardless of breast composition (fatty breasts: 32.7% to 24.1%m P = 0.002; dense breasts: 33.6% to 21.2%, P < 0.001). The reader-averaged AUC increased with AI assistance and was comparable to that of standalone AI (0.835 vs. 0.895; P = 0.234). The reader-averaged specificity (71.2% to 79.8%, P < 0.001) and accuracy (71.3% to 79.7%, P  < 0.001) significantly improved with AI assistance.

Conclusion

AI assistance significantly reduced false-positive recall without compromising cancer detection in women with focal asymmetry, mass, or architectural distortion on standard digital mammography regardless of mammographic breast density.

Abstract 5445: New discovery and development of transglutaminase 2 inhibitor

Transglutaminase 2 (TGase 2) is a multi-functional, ubiquitous enzyme that is important for various cellular processes, including apoptosis, development, differentiation, wound healing, and angiogenesis. TGase2 plays important roles in the pathogenesis of many diseases, including cancers, autoimmune pathologies, neurodegeneration, and Inflammation. Dysregulation of TGase 2 expression can both activate pathogenesis and aggravate disease state. TG2 is overexpressed in cancers such as renal cell carcinoma (RCC), pancreatic, triple negative breast (TNBC) and, gastric cancer, and is associated with poor prognosis. It is also involved in drug resistance and cancer cell metastasis. These evidences provide the rationale for the development of TGase2 inhibitors as novel anticancer agents. We selected TGase2 inhibitors from a library of compounds, validated and optimized a final compound. An optimized compound was synthesized by modifying aromatic substitution, various alkyl groups, and PK improvement in consideration of activity and physical properties and named as MD102. The IC50 value of TGase2 activity inhibition of MD102 is 100-400 nM similar to positive control of streptonigrin and IC50 of cell growth inhibition was 1~10 μM in TGase2 overexpressing RCC, TNBC and gastric cancer cell lines. The cell growth inhibitory dose of MD102 was depend on the expression level of TGase2. We observed MD102 inhibited cell growth through suppression of PI3K/AKT pathway (AKT, p-AKT, mTOR, p-mTOR). Also, MD102 has inhibited the growth of endothelial cell (HMVEC) with IC50 of 1.2nM and tube formation of HUVEC with 35%, suggesting antiangiogenic effect. The angiogenesis was inhibited by suppression of NFkB pathway including p50, p65, HIF1-a, and VEGF. Oral administration of MD102 once daily for 4 weeks showed significant tumor growth inhibition of 50% at 50mg/kg compare to control group in both xenograft models of the ACHN (RCC) and MDA-MB231 (TNBC) cell lines. And as a preliminary toxicity test, oral administration of MD102 up to 2000mg/kg for 3 weeks did not show deaths or any adverse reactions in body weight and laboratory tests of blood counts, liver and renal functions. MD102, a TGase2 inhibitor, is expected to be a potential candidate in TGase2-overexpressing cancers, including RCC and TNBC, as it shows antitumor activity without serious toxicity, although further validation is required. In addition, it is expected that area expansion to many diseases induced by TGase2 pathogenesis

Citation Format: Eun Yi Cho, Hyeon Joo Kim, Byeonghak Moon, Yerin Jo, Jinsu Bae, Ga Ram Kim, Yong-Chul Kim, Sun Kyoung Kang, Woo Sun Kwon, Tae Soo Kim, Sun Young Rha, Hyun Cheol Chung. New discovery and development of transglutaminase 2 inhibitor [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5445.

Geriatric functional assessment for decision-making on adjuvant chemotherapy in older colon cancer patients

BACKGROUND/AIMS

Despite the increasing need for geriatric assessment prior to chemotherapy, the method for this assessment remains inadequate for older cancer patients. We aimed to propose a simple assessment method to predict the performance of adjuvant chemotherapy in older patients after colon cancer surgery.

METHODS

This prospective study included patients over 65 years of age who were scheduled for adjuvant chemotherapy after colon cancer surgery. Before initiating chemotherapy, their functional status was assessed on the basis of activities of daily living (ADL)/instrumental activities of daily living (IADL). These parameters were analyzed with clinical characteristics and the patterns of adjuvant chemotherapy. The focus was on the completion rate of adjuvant chemotherapy.

RESULTS

A total of 89 patients with a median age of 72 years were analyzed. Among them, 54 (61%) were non-impaired and 35 (39%) were impaired regarding their ADL/IADL classification. Low body mass index and impairment of ADL/IADLs were significantly associated with chemotherapy interruption. Among toxicities, fatigue and hand-foot syndrome were independent prognostic factors for chemotherapy interruption. Impairments of ADL/IADL were significantly associated with fatigue regardless of age. Based on age and ADL/IADL stratification, younger patients (≤ 72 years) and/or those who were ADL/IADL non-impaired were significantly more likely to complete adjuvant chemotherapy than older patients (> 72 years) and ADL/IADL impaired patients (p = 0.038). This was regardless of the chemotherapy regimen.

CONCLUSION

Functional assessment using ADL/IADL is a convenient method to predict chemotherapy toxicity and performance. These results suggested that routine screening for ADL/IADLs could guide appropriate patient selection for the completion of adjuvant chemotherapy and predict expected outcomes.

US, Mammography, and Histopathologic Evaluation to Identify Low Nuclear Grade Ductal Carcinoma in Situ

Background Low nuclear grade ductal carcinoma in situ (DCIS) identified at biopsy can be upgraded to intermediate to high nuclear grade DCIS at surgery. Methods that confirm low nuclear grade are needed to consider nonsurgical approaches for these patients. Purpose To develop a preoperative model to identify low nuclear grade DCIS and to evaluate factors associated with low nuclear grade DCIS at biopsy that was not upgraded to intermediate to high nuclear grade DCIS at surgery. Materials and Methods In this retrospective study, 470 women (median age, 50 years; interquartile range, 44-58 years) with 477 pure DCIS lesions at surgical histopathologic evaluation were included (January 2010 to December 2015). Patients were divided into the training set (n = 330) or validation set (n = 147) to develop a preoperative model to identify low nuclear grade DCIS. Features at US (mass, nonmass) and at mammography (morphologic characteristics, distribution of microcalcification) were reviewed. The upgrade rate of low nuclear grade DCIS was calculated, and multivariable regression was used to evaluate factors for associations with low nuclear grade DCIS that was not upgraded later. Results A preoperative model that included lesions manifesting as a mass at US without microcalcification and no comedonecrosis at biopsy was used to identify low nuclear grade DCIS, with a high area under the receiver operating characteristic curve of 0.97 (95% CI: 0.94, 1.00) in the validation set. The upgrade rate of low nuclear grade DCIS at biopsy was 38.8% (50 of 129). Ki-67 positivity (odds ratio, 0.04; 95% CI: 0.0003, 0.43; P = .005) was inversely associated with constant low nuclear grade DCIS. Conclusion The upgrade rate of low nuclear grade ductal carcinoma in situ (DCIS) at biopsy to intermediate to high nuclear grade DCIS at surgery occurred in more than a third of patients; low nuclear grade DCIS at final histopathologic evaluation could be identified if the mass was viewed at US without microcalcifications and had no comedonecrosis at histopathologic evaluation of biopsy. © RSNA, 2022 Online supplemental material is available for this article. See also the editorial by Rahbar in this issue.

Chronological Trends of Breast Ductal Carcinoma In Situ: Clinical, Radiologic, and Pathologic Perspectives

BACKGROUND

Because no prior studies have evaluated the chronological trends of ductal carcinoma in situ (DCIS) despite the increasing number of surgeries performed for DCIS, this study analyzed how the clinical, radiologic, and pathologic characteristics of DCIS changed during a 10-year period.

METHODS

Of 7123 patients who underwent primary breast cancer surgery at a single institution from 2006 to 2015, 792 patients with pure DCIS were included in this study. The chronological trends of age, symptoms, method for detecting either mammography or ultrasonography, tumor size, nuclear grade, comedonecrosis, and molecular markers were calculated using Poisson regression for all patients and asymptomatic patients.

RESULTS

During 10 years, DCIS surgery rates significantly increased (p < 0.001). Despite the high percentage of DCIS detected on mammography, the detection rate for DCIS by mammography significantly decreased (97.3% in 2006 to 67.6% in 2015; p = 0.025), whereas the detection rate by ultrasound significantly increased (2.7% to 31.0%; p < 0.001). Conservation surgery rates (odds ratio [OR], 1.058), low-to-intermediate nuclear grade rates (OR, 1.069), and the absence of comedonecrosis (OR, 1.104) significantly increased over time (all p < 0.05). Estrogen receptor (ER) negativity (OR, 0.935) and human epidermal growth factor receptor 2 (HER2) positivity rates (OR, 0.953) significantly decreased (all p < 0.05). The same trends were observed for the 613 asymptomatic patients.

CONCLUSION

The rate of DCIS detected on ultrasound only significantly increased during 10 years. Low-to-intermediate nuclear grade rates significantly increased, whereas ER negativity and HER2 positivity rates significantly decreased during the same period. These findings suggest that DCIS detected on screening ultrasound is less aggressive than DCIS detected on mammography.

Interval Cancers after Negative Supplemental Screening Breast MRI Results in Women with a Personal History of Breast Cancer

Background There are few interval cancer studies of incident screening MRI for women with a personal history of breast cancer (PHBC). Purpose To evaluate the performance measures of screening breast MRI in women with a PHBC across multiple rounds and to identify subgroups who might be more at risk for interval cancer. Materials and Methods Between January 2008 and March 2019, consecutive screening breast MRI studies for women who had undergone breast-conserving surgery because of breast cancer were retrospectively identified. Inclusion criteria were negative or benign findings at mammography with US, availability of at least 1 year of follow-up data, and examinations having been performed within 12 months after the initial cancer surgery. Performance measures were calculated for each round. Multivariable logistic regression analysis was performed to determine factors associated with the risk of interval cancer. Results Among the 6603 MRI examinations for 2809 women (median age, 47 years; interquartile range, 42-53 years), the cancer detection rate was 8.3 per 1000 screening examinations (55 of 6603 examinations) and the interval cancer rate was 1.5 per 1000 screening examinations (10 of 6603 examinations). The sensitivity and specificity were 85% (55 of 65 examinations; 95% CI: 76, 93) and 88.3% (5775 of 6538 examinations; 95% CI: 87.6, 89.1), respectively. At multivariable analysis, interval cancers were associated with a first-degree family history of breast cancer (odds ratio [OR], 5.4; 95% CI: 1.3, 22.5; P = .02), estrogen receptor- and progesterone receptor-negative primary cancers (OR, 3.6; 95% CI: 1.1, 12.2; P = .04), and moderate or marked background parenchymal enhancement (OR, 10.8; 95% CI: 3.3, 35.7; P < .001). Conclusion Performance of screening breast MRI in women with a personal history of breast cancer was sustained across multiple rounds, and a first-degree family history of breast cancer, estrogen receptor- and progesterone receptor-negative primary cancers, and moderate or marked background parenchymal enhancement at MRI were independently associated with the risk of developing interval cancers. © RSNA, 2021 Online supplemental material is available for this article. See also the editorial by Slanetz in this issue.

Outcomes Following Negative Screening MRI Results in Korean Women with a Personal History of Breast Cancer: Implications for the Next MRI Interval

Background There are limited data on outcomes following screening breast MRI in women with a personal history of breast cancer (PHBC). Purpose To investigate outcomes and factors associated with subsequent cancers following a negative screening MRI study in women with a PHBC. Materials and Methods Consecutive women with a PHBC and a negative prevalence screening breast MRI result between August 2014 and December 2016 were retrospectively identified. Inclusion criteria were prevalence screening MRI performed as part of routine surveillance protocol (1-3 years after treatment) and follow-up data for at least 12 months. The incidence and characteristics of subsequent cancers were reviewed. Logistic regression analysis was used to investigate associations between clinical-pathologic characteristics and subsequent cancers. Performance metrics were compared among screening MRI, mammography, and US. Results A total of 993 women (mean age ± standard deviation, 53 years ± 10) were evaluated. Ten second in-breast cancers (ie, ipsilateral or contralateral) occurred at a median interval of 31.8 months (range, 13.3-44.8 months) after MRI, of which eight (80%) were ductal carcinoma in situ (DCIS) or node-negative T1 cancers. Only one node-negative T1mi (tumor ≤1 mm) second in-breast cancer visible on a mammogram was detected within 24 months of MRI. Of second in-breast cancers, 40% (four of 10) were detected only at subsequent screening MRI, which was performed a median of 30.5 months after negative prevalence screening MRI. Ten local-regional recurrences occurred at a median interval of 16.9 months (range, 6-35 months). Previous treatment for DCIS was associated with second in-breast cancers (odds ratio, 3.73; 95% CI: 1.04, 13.38; P = .04). In 1048 women who underwent prevalence screening MRI (including all Breast Imaging Reporting and Data System categories), MRI showed a lower abnormal interpretation rate and higher specificity than mammography or US (P < .001 for all). Conclusion After a negative screening MRI result, 90% of subsequent cancers were detected at intervals longer than 24 months and there was a low second in-breast cancer rate (1%). © RSNA, 2021 Supplemental material is available for this article. See also the editorial by Chang in this issue.

Convolutional Neural Network to Stratify the Malignancy Risk of Thyroid Nodules: Diagnostic Performance Compared with the American College of Radiology Thyroid Imaging Reporting and Data System Implemented by Experienced Radiologists

BACKGROUND AND PURPOSE

Comparison of the diagnostic performance for thyroid cancer on ultrasound between a convolutional neural network and visual assessment by radiologists has been inconsistent. Thus, we aimed to evaluate the diagnostic performance of the convolutional neural network compared with the American College of Radiology Thyroid Imaging Reporting and Data System (TI-RADS) for the diagnosis of thyroid cancer using ultrasound images.

MATERIALS AND METHODS

From March 2019 to September 2019, seven hundred sixty thyroid nodules (≥10 mm) in 757 patients were diagnosed as benign or malignant through fine-needle aspiration, core needle biopsy, or an operation. Experienced radiologists assessed the sonographic descriptors of the nodules, and 1 of 5 American College of Radiology TI-RADS categories was assigned. The convolutional neural network provided malignancy risk percentages for nodules based on sonographic images. Sensitivity, specificity, accuracy, positive predictive value, and negative predictive value were calculated with cutoff values using the Youden index and compared between the convolutional neural network and the American College of Radiology TI-RADS. Areas under the receiver operating characteristic curve were also compared.

RESULTS

Of 760 nodules, 176 (23.2%) were malignant. At an optimal threshold derived from the Youden index, sensitivity and negative predictive values were higher with the convolutional neural network than with the American College of Radiology TI-RADS (81.8% versus 73.9%, P = .009; 94.0% versus 92.2%, P = .046). Specificity, accuracy, and positive predictive values were lower with the convolutional neural network than with the American College of Radiology TI-RADS (86.1% versus 93.7%, P < .001; 85.1% versus 89.1%, P = .003; and 64.0% versus 77.8%, P < .001). The area under the curve of the convolutional neural network was higher than that of the American College of Radiology TI-RADS (0.917 versus 0.891, P = .017).

CONCLUSIONS

The convolutional neural network provided diagnostic performance comparable with that of the American College of Radiology TI-RADS categories assigned by experienced radiologists.

Combining radiomics with ultrasound-based risk stratification systems for thyroid nodules: an approach for improving performance

OBJECTIVES

To develop a radiomics score using ultrasound images to predict thyroid malignancy and to investigate its potential as a complementary tool to improve the performance of risk stratification systems.

METHODS

We retrospectively included consecutive patients who underwent fine-needle aspiration (FNA) for thyroid nodules that were cytopathologically diagnosed as benign or malignant. Nodules were randomly assigned to a training and test set (8:2 ratio). A radiomics score was developed from the training set, and cutoff values based on the maximum Youden index (Rad_maxY) and for 5%, 10%, and 20% predicted malignancy risk (Rad_5%, Rad_10%, Rad_20%, respectively) were applied to the test set. The performances of the American College of Radiology (ACR) and the American Thyroid Association (ATA) guidelines were compared with the combined performances of the guidelines and radiomics score with interpretations from expert and nonexpert readers.

RESULTS

A total of 1624 thyroid nodules from 1609 patients (mean age, 50.1 years [range, 18-90 years]) were included. The radiomics score yielded an AUC of 0.85 (95% CI: 0.83, 0.87) in the training set and 0.75 (95% CI: 0.69, 0.81) in the test set (Rad_maxY). When the radiomics score was combined with the ACR or ATA guidelines (Rad_5%), all readers showed increased specificity, accuracy, and PPV and decreased unnecessary FNA rates (all p < .05), with no difference in sensitivity (p > .05).

CONCLUSION

Radiomics help predict thyroid malignancy and improve specificity, accuracy, PPV, and unnecessary FNA rate while maintaining the sensitivity of the ACR and ATA guidelines for both expert and nonexpert readers.

KEY POINTS

• The radiomics score yielded an AUC of 0.85 and 0.75 in the training and test set, respectively. • For all readers, combining a 5% predicted malignancy risk cutoff for the radiomics score with the ACR and ATA guidelines significantly increased specificity, accuracy, and PPV and decreased unnecessary FNA rates, with no decrease in sensitivity. • Radiomics can help predict malignancy in thyroid nodules in combination with risk stratification systems, by improving specificity, accuracy, and PPV and unnecessary FNA rates while maintaining sensitivity for both expert and nonexpert readers.

Impact of Adjuvant Chemotherapy Completion on Oncologic Outcomes in ypTNMstage 2 Rectal Cancer Patients

PURPOSE

Adjuvant chemotherapy (aCT) in rectal cancer patients who have undergone curative resection after neoadjuvant chemoradiation (nCRT) is controversial. We aimed to investigate the benefits of using aCT and the clinical impact of completing aCT in ypstage 2 rectal cancer patients.

METHODS

We retrospectively reviewed clinicopathological data from patients who had undergone radical resection after nCRT between January 2006 and December 2012. In total, 152 patients with ypT3/4N0M0 rectal cancer were included. Of these patients, 139 initiated aCT, while 13 did not receive aCT (no-aCT). Among those who received aCT, 132 patients completed their planned cycles (aCT-completion) whereas 7 did not (aCT-incompletion). All patients received longcourse chemoradiation; a 5-fluorouracil-based regimen was used for nCRT in most patients. The prognostic factors affecting disease-free survival (DFS) and overall survival (OS) were analyzed.

RESULTS

The median follow-up duration was 41 months. Demographic data did not differ significantly among the 3 groups. In multivariate analysis, open surgery, a tumor size >2 cm, retrieval of <12 lymph nodes, circumferential resection margin (CRM) positivity and aCT incompletion were independent prognostic factors for poor DFS. Old age (≥60 years), open surgery, CRM positivity, aCT incompletion, and lack of aCT initiation compared to aCT completion were independent prognostic factors for poor OS.

CONCLUSION

In ypstage 2 rectal cancer patients, aCT after nCRT and total mesorectal excision affected both DFS and OS; however, only patients who completed planned aCT exhibited survival benefits. Therefore, improving patients' compliance with the completion of aCT is desirable.

Correlation between MR Image-Based Radiomics Features and Risk Scores Associated with Gene Expression Profiles in Breast Cancer

Purpose

To investigate the correlation between magnetic resonance (MR) image-based radiomics features and the genomic features of breast cancer by focusing on biomolecular intrinsic subtypes and gene expression profiles based on risk scores.

Materials and Methods

We used the publicly available datasets from the Cancer Genome Atlas and the Cancer Imaging Archive to extract the radiomics features of 122 breast cancers on MR images. Furthermore, PAM50 intrinsic subtypes were classified and their risk scores were determined from gene expression profiles. The relationship between radiomics features and biomolecular characteristics was analyzed. A penalized generalized regression analysis was performed to build prediction models.

Results

The PAM50 subtype demonstrated a statistically significant association with the maximum 2D diameter (p = 0.0189), degree of correlation (p = 0.0386), and inverse difference moment normalized (p = 0.0337). Among risk score systems, GGI and GENE70 shared 8 correlated radiomic features (p = 0.0008–0.0492) that were statistically significant. Although the maximum 2D diameter was most significantly correlated to both score systems (p = 0.0139, and p = 0.0008), the overall degree of correlation of the prediction models was weak with the highest correlation coefficient of GENE70 being 0.2171.

Conclusion

Maximum 2D diameter, degree of correlation, and inverse difference moment normalized demonstrated significant relationships with the PAM50 intrinsic subtypes along with gene expression profile-based risk scores such as GENE70, despite weak correlations.

Outcomes of Ductal Carcinoma In Situ According to Detection Modality: A Multicenter Study Comparing Recurrence Between Mammography and Breast US

The purpose of this study was to determine whether disease recurrence and intrinsic characteristics of ductal carcinoma in situ (DCIS) are associated with the imaging method of detection in asymptomatic women. This multicenter, retrospective study included 844 women treated for asymptomatic DCIS who had pre-operative mammography and breast ultrasonography (US) studies available. Of the 844 women, 25 (3.0%) developed recurrences. Patients in the US group had significantly lower 5- and 10-y recurrence-free survival (RFS) rates compared with patients in the mammography group (p = 0.011). US-detected DCIS showed significantly lower 5-and 10-y RFS rates compared with mammography-detected DCIS in patients <50 y or with mammographically dense breasts (p = 0.002 and 0.002, respectively). US as the detection modality (hazard ratio [HR]: 4.451; 95% confidence interval [CI]: 1.530, 12.950; p = 0.006) and HER2 positivity (HR: 4.036; 95% CI: 1.438; 11.330; p = 0.008) were significantly associated with recurrence. We concluded that US as the detection modality and HER2 positivity were significantly associated with recurrence in patients treated for asymptomatic DCIS.

Clinicopathological and biomolecular characteristics of stage IIB/IIC and stage IIIA colon cancer: Insight into the survival paradox

BACKGROUND

A survival paradox of stage IIB/IIC and IIIA colon cancer has been consistently observed throughout revisions of the TNM system. This study aimed to understand this paradox with clinicopathological and molecular differences.

METHODS

Clinicopathological characteristics of patients with pathologically confirmed stage IIB/IIC or IIIA colon cancer were retrospectively reviewed from a database. Publicly available molecular data were retrieved, and intrinsic subtypes were identified and subjected to gene sets enrichment analysis (GSEA).

RESULTS

Among the 159 patients included in the clinicopathological analysis, those at stage IIB/IIC had worse 3-year disease-free and overall survival than those at stage IIIA (59.3% vs 91.7%, P < 0.001 and 82.7% vs 98.5%, P < 0.001, respectively), even after adjusting for confounding factors. Data of 95 patients were retrieved from public databases, demonstrating a higher frequency of the microsatellite instable subtype in stage IIB/IIC. The consensus molecular subtype distribution pattern differed between the groups. The GSEA further suggested the protumor inflammatory reaction might be more prominent in stage IIB/IIC.

CONCLUSIONS

The survival paradox in colon cancer was confirmed and appears to be a multifactorial phenomenon not attributed to a single clinicopathologic factor. However, the greater molecular heterogeneity in stage IIB/IIC could contribute to the poor prognosis.

Characteristics, trend, and methodological quality of systematic reviews and meta-analyses in nuclear medicine: A bibliometric analysis of studies published between 2005 and 2016

To evaluate the characteristics, trend, and quality of systematic reviews and meta-analyses in nuclear medicine.We performed a PubMed search to identify systematic reviews and meta-analyses published between 2005 and 2016 in the field of nuclear medicine. The following data were extracted: journal name, impact factor, type of study, topics with cancer type, imaging modalities, authors (number, country, affiliation, presence of nuclear medicine specialists and statisticians, discordance between the first and corresponding authors), funding, methodological quality, methods used for quality assessment, and statistical methods.We included 185 nuclear medicine articles. Meta-analyses (n = 164; 88.6%) were published about 7 times more frequently than systematic reviews. Oncology was the most commonly studied topic (n = 125, 67.6%). The first authors were most frequently located in China (n = 73; 39.5%). PET was the most commonly used modality (n = 150; 81.1%). Both the number of authors and the ratio of discordance between the first and corresponding authors tended to progressively increase over time.The mean AMSTAR score increased over time (5.77 in 2005-2008, 6.71 in 2009-2012, and 7.44 in 2013-2016). The proportion of articles with quality assessment increased significantly (20/26 in 2005-2008, 54/65 in 2009-2012, and 79/94 in 2013-2016). The most commonly used assessment tool was quality assessment of diagnostic accuracy studies (n = 85; 54.9%).The number and quality of systematic reviews and meta-analyses in nuclear medicine have significantly increased over the review period; however, the quality of these articles varies. Efforts to overcome specific weaknesses of the methodologies can provide opportunities for quality improvement.

Comparison of Ultrasound Elastography and Color Doppler Ultrasonography for Distinguishing Small Triple-Negative Breast Cancer From Fibroadenoma

OBJECTIVES

To compare the performance of ultrasound elastography and color Doppler ultrasonography (US) in distinguishing small, oval, or round triple-negative breast cancer from fibroadenoma and the influence on the further management decision at US.

METHODS

In total, 131 biopsy-proven oval or round fibroadenomas (n = 68) and triple-negative breast cancers (n = 63) smaller than 2 cm were included. Three blinded readers assessed the images from US, elastography, and color Doppler imaging according to the Breast Imaging Reporting and Data System lexicon independently. Interobserver agreement was assessed, and sensitivity, specificity, accuracy, and area under the receiver operating characteristic curve values for each data set were compared. Pathologic results were reference standards.

RESULTS

The interobserver agreements were excellent (intraclass correlation coefficients, 0.856 for US, 0.948 for elastography, and 0.864 for color Doppler). The specificity and accuracy of US with elastography were increased compared with US alone or US with Doppler imaging without statistically significant differences in sensitivity. The average area under the curve for US with elastography (0.869) was increased compared with US alone (0.650) or US with color Doppler (0.576).

CONCLUSIONS

Elastography is more useful than color Doppler imaging for distinguishing small, oval, or round triple-negative breast cancer from fibroadenoma, and elastography can help avoid biopsy of benign masses.

Comparison of synthetic and digital mammography with digital breast tomosynthesis or alone for the detection and classification of microcalcifications

OBJECTIVE

To compare the performance of synthetic mammography (SM) and digital mammography (DM) with digital breast tomosynthesis (DBT) or alone for the evaluation of microcalcifications.

METHODS

This retrospective study includes 198 mammography cases, all with DM, SM, and DBT images, from January to October 2013. Three radiologists interpreted images and recorded the presence of microcalcifications and their conspicuity scores and final BI-RADS categories (1, 2, 3, 4a, 4b, 4c, 5). Readers' area under the ROC curves (AUCs) were analyzed for SM plus DBT vs. DM plus DBT and SM alone vs. DM alone using the BI-RADS categories for the overall group and dense breast subgroup.

RESULTS

Conspicuity scores of detected microcalcifications were neither significantly different between SM and DM with DBT nor alone (p>0.05). In predicting malignancy of detected microcalcifications, no significant difference was found between readers' AUCs for SM and DM with DBT or alone in the overall group or dense breast subgroup (p>0.05).

CONCLUSIONS

Diagnostic performances of SM and DM for the evaluation of microcalcifications are not significantly different, whether performed with DBT or alone.

KEY POINTS

• In DBT-imaging, SM and DM show comparable performances when evaluating microcalcifications. • For BI-RADS classification of microcalcifications, SM and DM show similar AUCs. • DBT with SM may be sufficient for diagnosing microcalcifications, without DM.

Acute gastroesophageal intussusception in a patient with pneumomediastinum, pneumoperitoneum, and extensive subcutaneous emphysema resulting from iatrogenic colonic perforation

Acute gastroesophageal intussusception is a rare condition in which the stomach invaginates into the adjacent esophagus. We report a case of acute gastroesophageal intussusception with massive pneumomediastinum, pneumoperitoneum, and subcutaneous emphysema, effectively treated with conservative management.

Associations between gene expression profiles of invasive breast cancer and Breast Imaging Reporting and Data System MRI lexicon

Purpose

To evaluate whether the Breast Imaging Reporting and Data System (BI-RADS) MRI lexicon could reflect the genomic information of breast cancers and to suggest intuitive imaging features as biomarkers.

Methods

Matched breast MRI data from The Cancer Imaging Archive and gene expression profile from The Cancer Genome Atlas of 70 invasive breast cancers were analyzed. Magnetic resonance images were reviewed according to the BI-RADS MRI lexicon of mass morphology. The cancers were divided into 2 groups of gene clustering by gene set enrichment an alysis. Clinicopathologic and imaging characteristics were compared between the 2 groups.

Results

The luminal subtype was predominant in the group 1 gene set and the triple-negative subtype was predominant in the group 2 gene set (55 of 56, 98.2% vs. 9 of 14, 64.3%). Internal enhancement descriptors were different between the 2 groups; heterogeneity was most frequent in group 1 (27 of 56, 48.2%) and rim enhancement was dominant in group 2 (10 of 14, 71.4%). In group 1, the gene sets related to mammary gland development were overexpressed whereas the gene sets related to mitotic cell division were overexpressed in group 2.

Conclusion

We identified intuitive imaging features of breast MRI associated with distinct gene expression profiles using the standard imaging variables of BI-RADS. The internal enhancement pattern on MRI might reflect specific gene expression profiles of breast cancers, which can be recognized by visual distinction.

Combination of shear-wave elastography and color Doppler: Feasible method to avoid unnecessary breast excision of fibroepithelial lesions diagnosed by core needle biopsy

Background

We evaluated shear-wave elastography (SWE) and color Doppler ultrasonography (US) features for fibroepithelial lesions (FELs), and to evaluate their utility to differentiate fibroadenomas (FAs) and phyllodes tumors (PTs).

Methods

This retrospective study included 67 FELs pathologically confirmed (49 FAs, 18 PTs). B-mode US, SWE and color Doppler US were performed for each lesion. Mean elasticity (E_mean), maximum elasticity (E_max), and vascularity were determined by SWE and Doppler US. Diagnostic performances were calculated to differentiate FAs and PTs. Equivocal FELs diagnosed by core needle biopsy (CNB) were further analyzed.

Results

Median E_mean and E_max were significantly lower for FAs than PTs (E_mean, 15.7 vs. 66.7 kPa; E_max, 21.0 vs. 76.7 kPa, P<0.01). Low vascularity (0–1 vessel flow) on color Doppler US were more frequent in FAs than in PTs (P<0.01). SWE showed significantly higher specificities (E_mean >43.9 kPa, 89.8%; E_max >46.1 kPa, 79.6%) than B-mode US (42.9%) (P<0.01) for differentiating PTs from FAs. Other diagnostic values of SWE and overall diagnostic values of Doppler US were not significantly different from B-mode US (P>0.05). The combination of SWE and Doppler US with ‘E_mean>43.9 kPa or high vascularity (≥2 vessel flows)’ showed a higher area under the curve (0.786 vs. 0.687) and higher diagnostic values than B-mode US (sensitivity, 100 vs. 94.4%; specificity, 57.1 vs. 42.9%; positive predictive value, 46.2 vs. 37.8%; negative predictive value, 100 vs. 95.5%), without statistical significance (P>0.05). Of the 30 equivocal FELs, all lesions with ‘E_mean≤43.9 kPa and low vascularity (0–1 vessel flow)’ (23.3%, 7/30) were finally confirmed as FAs by excision.

Conclusion

FAs have a tendency to have less stiffness and lower vascularity than PTs. Combined SWE and color Doppler US may help patients with equivocal FELs diagnosed by CNB avoid unnecessary excision.

Clinical predictors of chest radiographic abnormalities in young children hospitalized with bronchiolitis: a single center study

Purpose

Chest radiography is often performed on patients hospitalized with typical clinical manifestations of bronchiolitis. We aimed to determine the proportion of subjects with pathologic chest radiographic findings and the clinical predictors associated with pathologic chest radiographic findings in young children admitted with the typical presentation of bronchiolitis.

Methods

We obtained the following data at admission: sex, age, neonatal history, past history of hospitalization for respiratory illnesses, heart rate, respiratory rate, the presence of fever, total duration of fever, oxygen saturation, laboratory parameters (i.e., complete blood cell count, high-sensitivity C-reactive protein [hs-CRP], etc.), and chest radiography.

Results

The study comprised 279 young children. Of these, 26 had a chest radiograph revealing opacity (n=24) or atelectasis (n=2). Multivariate logistic regression analysis showed that after adjustment for confounding factors, the clinical predictors associated with pathologic chest radiographic findings in young children admitted with bronchiolitis were elevated hs-CRP level (>0.3 mg/dL) and past history of hospitalization for respiratory illnesses (all P<0.05).

Conclusion

The current study suggests that chest radiographs in young children with typical clinical manifestations of bronchiolitis have limited value. Nonetheless, young children with clinical factors such as high hs-CRP levels at admission or past history of hospitalization for respiratory illnesses may be more likely to have pathologic chest radiographic findings.

Association between Bethesda Categories and Ultrasound Features of Conventional Papillary Thyroid Carcinoma

The association between categories 3, 5 and 6 of the Bethesda System for Reporting Thyroid Cytopathology and the clinical and ultrasonography (US) features of conventional papillary thyroid carcinoma (PTC) was evaluated. We included 2005 patients diagnosed with conventional PTC at surgery and Bethesda categories 3, 5 and 6 at pre-operative US-guided fine-needle aspiration. Multinomial regression analysis was performed to determine the odds ratio (ORs) of each US feature associated with category 3 or 5, with category 6 as reference. Category 3 and 5 PTCs were smaller (ORs = 0.925 and 0.937) and did not exhibit marked hypo-echogenicity (ORs = 0.341 and 0.268) compared with category 6 PTCs. Category 3 and 5 PTCs exhibited significant macrocalcification (ORs = 2.372 and 1.594) and heterogeneous parenchyma (OR = 1.265 in category 5). In conclusion, conventional PTCs pre-operatively aspirated as Bethesda category 3, 5 or 6 significantly differ in size, macrocalcification, underlying thyroid parenchymal echogenicity and final assessment of US features.

Ultrasonographic features and clinical characteristics of Warthin-like variant of papillary thyroid carcinoma

Warthin-like variant of papillary thyroid carcinoma (WVPTC) is a rare entity recently characterized. We evaluated ultrasonographic (US) features and clinical characteristics of WVPTC. Nine patients were diagnosed with WVPTC through surgery in our institution from May 2005 to January 2015. Eight of nine patients had available preoperative US images. A retrospective review of the US and clinical characteristics was performed. WVPTC compromised of 0.06% of 14,071 PTCs surgically confirmed. A mean age of nine patients was 53.2 years (range, 32-75 years). The mean nodule size of nine WVPTCs was 0.9 cm (range, 0.5-1.5 cm). Two patients showed central nodal metastasis and one patient with conventional PTC as an index tumor underwent central and lateral neck dissection. No one showed recurrence or distant metastasis during the follow-up period (mean, 4.6 years; range, 0.6-10 years). The most common US features of WVPTCs were solid composition (62.5%), hypoechogenicity (75%), and wider-than-tall shape (100%), respectively. Four (50%) of eight nodules showed well-defined margin and three (37.5%) of them had cystic component. One of eight resembled focal thyroiditis. Three nodules were considered as probably benign with US. All nine cases demonstrated underlying heterogeneous parenchymal echogenicity and accompanied chronic lymphocytic thyroiditis in permanent sections. Thyroid function tests in all patients were normal except for one with subclinical hypothyroidism. WVPTC is an uncommon subtype of PTC and has favorable prognosis, which can be misdiagnosed as a probably benign nodule or focal thyroiditis with US. All cases are associated with heterogeneous parenchyma in the background.

Evaluation of Underlying Lymphocytic Thyroiditis With Histogram Analysis Using Grayscale Ultrasound Images

OBJECTIVES

The purpose of this study was to evaluate diagnostic performance of histogram analysis using grayscale ultrasound (US) images in the diagnosis of lymphocytic thyroiditis.

METHODS

Three radiologists reviewed a total of 505 US images and classified the images according to the presence/existence of lymphocytic thyroiditis. After 2 months, each reviewer repeated the process with the same 505 images in a randomly mixed order. The intraobserver and interobserver variability was analyzed with a generalized κ value. Four histogram parameters (mean value, standard deviation, skewness, and kurtosis) were obtained, and an index was calculated from principal component analysis. Diagnostic performances were compared.

RESULTS

Of 505 patients, 125 (24.8%) had lymphocytic thyroiditis, and 380 (75.2%) had normal thyroid parenchyma on pathologic analysis. The κ value for intraobserver variance ranged from -0.002 to 0.781, and the overall κ values for interobserver variance were 0.570 and 0.214 in the first and second tests, respectively. The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value for the 3 reviewers versus the principal component analysis index were 28.0% to 83.2%, 43.7% to 82.6%, 53.5% to 79.0%, 24.6% to 56.2%, and 75.2% to 88.9% versus 58.4%, 72.4%, 68.9%, 41.0%, and 84.1%.

CONCLUSIONS

Histogram analysis of grayscale US images provided confirmable and quantitative information about lymphocytic thyroiditis and was comparable with performers' assessments in diagnostic performance.

Development of an Ergonomics Checklist for Investigation of Work-Related Whole-Body Disorders in Farming - AWBA: Agricultural Whole-Body Assessment

Researchers have been using various ergonomic tools to study occupational musculoskeletal diseases in industrial contexts. However, in agricultural work, where the work environment is poorer and the socio-psychological stress is high due to the high labor intensities of the industry, current research efforts have been scarce, and the number of available tools is small. In our preliminary studies, which focused on a limited number of body parts and other working elements, we developed separate evaluation tools for the upper and lower extremities. The current study was conducted to develop a whole-body ergonomic assessment tool for agricultural work that integrates the existing assessment tools for lower and upper extremities developed in the preliminary studies and to verify the relevance of the integrated assessment tool. To verify the relevance of the Agricultural Whole-Body Assessment (AWBA) tool, we selected 50 different postures that occur frequently in agricultural work. Our results showed that the AWBA-determined risk levels were similar to the subjective risk levels determined by experts. In addition, as the risk level increased, the average risk level increased to a similar extent. Moreover, the differences in risk levels between the AWBA and expert assessments were mostly smaller than the differences in risk levels between other assessment tools and the expert assessments in this study. In conclusion, the AWBA tool developed in this study was demonstrated to be appropriate for use as a tool for assessing various postures commonly assumed in agricultural work. Moreover, we believe that our verification of the assessment tools will contribute to the enhancement of the quality of activities designed to prevent and control work-related musculoskeletal diseases in other industries.

Additional diagnostic value of shear-wave elastography and color Doppler US for evaluation of breast non-mass lesions detected at B-mode US

OBJECTIVE

To evaluate the diagnostic value of shear-wave elastography (SWE) and colour Doppler ultrasound (US) for evaluation of breast non-mass lesions (NMLs) detected by B-mode US.

METHODS

This retrospective study enrolled 116 NMLs (42 benign, 74 malignant). For each lesion, B-mode US, SWE and colour Doppler US were performed. Mean elasticity (E mean), maximum elasticity (E max) and vascularity were assessed by SWE and Doppler US. Diagnostic performances of B-mode US, SWE and Doppler US were calculated to differentiate benign and malignant NMLs.

RESULTS

In benign NMLs, average E mean and E max were lower, and low vascularity (no flow or only one vessel flow) was more frequent (P < 0.001). When BI-RADS category 4a NMLs were downgraded to category 3 with 'E mean of 85.1 kPa or less' and/or 'low vascularity', specificities increased (69.0-90.5 %; P < 0.001), without significant loss in sensitivities (97.3-100 %). When these 4a NMLs were downgraded by the combination of SWE and Doppler US, all downgraded NMLs (59.3 %, 19/32) were confirmed as benign.

CONCLUSIONS

Addition of SWE and colour Doppler US to B-mode US improved diagnostic performances in differentiating benign and malignant NMLs. This study suggests that the combination of SWE and colour Doppler may help patients with BI-RADS category 4a NMLs avoid unnecessary biopsies.

KEY POINTS

• B-mode US features of malignant and benign NMLs may overlap. • SWE and colour Doppler provides useful information about breast NMLs. • SWE and colour Doppler may decrease unnecessary biopsies of breast NMLs.

Extracts from Aralia elata (Miq) Seem alleviate hepatosteatosis via improving hepatic insulin sensitivity

Background

Non-alcoholic fatty liver disease (NAFLD) is a common liver disease that is strongly associated with obesity and dysregulation of insulin in the liver. However, currently no pharmacological agents have been established for the treatment of NAFLD. In this regard, we sought to evaluate the anti-NAFLD effects of Aralia elata (Miq) Seem (AE) extract and its ability to inhibit hepatic lipid accumulation and modulate cellular signaling in a high fat diet (HFD)-induced obese mouse model.

Methods

A model of hepatic steatosis in the HepG2 cells was induced by oleic acid. Intracellular lipid droplets were detected by Oil-Red-O staining, and the expression of sterol regulatory element-binding protein 1(SREBP-1), Fatty acid synthase (FAS), Acetyl-CoA carboxylase (ACC) 1 and 2, Peroxisome proliferator activated receptor-α (PPARα), and carnitine palmitoyl transferase 1(CPT-1) was analyzed by real time reverse transcription–Polymerase chain reaction (qRT–PCR). And glucose consumption was measured with commercial kit. Furthermore, Male C57BL/6 J mice were fed with HFD to induce NAFLD. Groups of mice were given plant extracts orally at 100 and 300 mg/kg at daily for 4 weeks. After 3 weeks of AE extract treatment, we performed oral glucose tolerance test (OGTT). Liver tissue was procured for histological examination, Phosphoinositide 3-kinase (PI3K) and Protein kinase B (PKB/Akt) activity.

Results

In the present study, AE extract was shown to reduce hepatic lipid accumulation and significantly downregulate the level of lipogenic genes and upregulate the expression of lipolysis genes in HepG2 cells. And also, AE extract significantly increased the glucose consumption, indicating that AE extract improved insulin resistance. Subsequently, we confirmed the inhibitory activity of AE extract on NAFLD, in vivo. Treatment with AE extract significantly decreased body weight and the fasting glucose level, alleviated hyperinsulinism and hyperlipidemia, and reduced glucose levels, as determined by OGTT. Additionally, AE extract decreased PI3K and Akt activity.

Conclusions

Our results suggest that treatment with AE extract ameliorated NAFLD by inhibiting insulin resistance through activation of the Akt/GLUT4 pathway.

Electronic supplementary material

The online version of this article (doi:10.1186/s12906-015-0871-5) contains supplementary material, which is available to authorized users.

Food allergen sensitization in young children with typical signs and symptoms of immediate-type food allergies: a comparison between monosensitized and polysensitized children

PURPOSE

The clinical interpretation of children sensitized to allergens is challenging, particularly in children with food allergies. We aimed to examine clinical differences between children with monosensitization and those with polysensitization to common food allergens and to determine risk factors for polysensitization in young children <10 years of age with immediate-type food allergies.

METHODS

The study included children <10 years of age with signs and symptoms indicative of immediate-type food allergies. Serum total IgE level was measured, and ImmunoCAP analysis for food allergens was performed.

RESULTS

The mean age of the study subjects was 1.6±1.6 years (75 boys and 51 girls). Thirty-eight children (30.2%) were monosensitized and 88 children (69.8%) were polysensitized. Multivariate logistic regression analysis showed that the development of polysensitization to common food allergens was positively associated with a parental history of allergic rhinitis (adjusted odds ratio [aOR], 6.28; 95% confidence interval [CI], 1.78-22.13; P=0.004), season of birth (summer/fall) (aOR, 3.10; 95% CI, 1.10-8.79; P=0.033), and exclusive breastfeeding in the first 6 months of age (aOR, 3.51; 95% CI, 1.20-10.25; P=0.022).

CONCLUSION

We found significant clinical differences between children with monosensitization and those with polysensitization to common food allergens and identified risk factors for the development of polysensitization in young children with immediate-type food allergies. Clinicians should consider these clinical risk factors when evaluating, counseling, treating, and monitoring young children with food allergies.

Photoacoustic imaging of breast microcalcifications: a validation study with 3-dimensional ex vivo data and spectrophotometric measurement

This paper investigates whether photoacoustic imaging (PAI) can provide the visualization of microcalcifications in breast tissue. For this, the geometrical correlation between the 3-D PA images of breast microcalcifications within ex vivo specimens and the corresponding mammograms was ascertained. Also, the optical absorbance of the calcification compositions (i.e., hydroxyapatite and calcium oxalate) was measured and compared with the PA responses of the microcalcifications. The experimental results demonstrated that the PA images discriminated between the microcalcifications and the surrounding tissue, and their locations in PA images reasonably meshed with those of the microcalcifications appeared in the mammograms. Also, the change in PA signal amplitude along the laser wavelength agreed with the absorbance of hydroxyapatite associated with the relatively high potential of malignant cancers, but not calcium oxalate with only benign cases.

Photoacoustic imaging of breast microcalcifications: a preliminary study with 8-gauge core-biopsied breast specimens

Background

We presented the photoacoustic imaging (PAI) tool and to evaluate whether microcalcifications in breast tissue can be detected on photoacoustic (PA) images.

Methods

We collected 21 cores containing microcalcifications (n = 11, microcalcification group) and none (n = 10, control group) in stereotactic or ultrasound (US) guided 8-gauge vacuum-assisted biopsies. Photoacoustic (PA) images were acquired through ex vivo experiments by transmitting laser pulses with two different wavelengths (700 nm and 800 nm). The presence of microcalcifications in PA images were blindly assessed by two radiologists and compared with specimen mammography. A ratio of the signal amplitude occurring at 700 nm to that occurring at 800 nm was calculated for each PA focus and was called the PAI ratio.

Results

Based on the change of PA signal amplitude between 700 nm and 800 nm, 10 out of 11 specimens containing microcalcifications and 8 out of 10 specimens without calcifications were correctly identified on blind review; the sensitivity, specificity, accuracy, positive predictive and negative predictive values of our blind review were 90.91%, 80.0%, 85.71%, 83.33% and 88.89%. The PAI ratio in the microcalcification group was significantly higher than that in the control group (the median PAI ratio, 2.46 versus 1.11, respectively, P = .001). On subgroup analysis in the microcalcification group, neither malignant diagnosis nor the number or size of calcification-foci was proven to contribute to PAI ratios.

Conclusion

Breast microcalcifications generated distinguishable PA signals unlike breast tissue without calcifications. So, PAI, a non-ionizing and non-invasive hybrid imaging technique, can be an alternative in overcoming the limitations of conventional US imaging.

Benign Aspirates on Follow-Up FNA May Be Enough in Patients with Initial Atypia of Undetermined Significance/Follicular Lesion of Undetermined Significance

Background. Management of thyroid nodules with benign aspirates following atypia of undetermined significance/follicular lesion of undetermined significance (AUS/FLUS) is not well established. We reviewed the risk of malignancy and the role of ultrasound (US) features among thyroid nodules with benign results following initial AUS/FLUS diagnoses. Methods. From December 2009 to February 2011, a total of 114 nodules in 114 patients diagnosed as benign on follow-up fine-needle aspiration (FNA) after AUS/FLUS results were included in our study. Eight among 114 nodules were confirmed pathologically and 106 were clinically observed by a follow-up FNA or US. Suspicious US features were defined as markedly hypoechogenicity, irregular or microlobulated margin, presence of microcalcifications, and taller than wide shape. Results. There were 110 (96.5%) benign nodules and 4 (3.5%) malignant nodules. Two (4.8%) among 42 nodules without suspicious US features and 2 (2.8%) out of 72 nodules with suspicious US features were confirmed as malignancy, but there were no significant associations between the malignancy rate and US features (P = 0.625). Conclusion. Clinical follow-up instead of surgical excision or continuous repeat FNA may be enough for benign thyroid nodules after AUS/FLUS. The role of US features might be insignificant in the management of these nodules.

Sonographic features and ultrasonography-guided fine-needle aspiration of metastases to the thyroid gland

Purpose:

To evaluate the characteristic ultrasonographic (US) features of metastatic carcinoma to the thyroid, and how accurate US features and ultrasonography-guided fine-needle aspiration (US-FNA) are for the diagnosis of thyroid metastases.

Methods:

Twenty-three thyroid lesions in 23 patients (mean age, 66.7 years; range, 46 to 85 years) that had been diagnosed as thyroid metastases were included. The composition, echogenicity, margin, shape, presence of calcifications, underlying parenchymal echotexture, and vascularity were analyzed in US images of the thyroid metastases. Final US assessments were categorized into probably benign and suspicious malignancy. The presence of suspicious metastatic cervical lymph nodes was noted. The medical records, US-FNA cytology, and pathology reports of these patients were retrospectively reviewed.

Results:

Of the 23 thyroid lesions, the general US appearance was mass-forming in 21 (91.3%) and non-mass-forming in 2 (8.7%). All 23 lesions showed a solid tumor composition. Common US features among the 21 mass-forming thyroid metastases were hypoechogenicity (81.0%), non-circumscribed margins (90.5%), no calcifications (76.2%), and parallel shape (81.0%). Suspicious cervical lymph nodes were present in 18 patients (78.3%). Of the 23 lesions, 21 (91.3%) were classified as suspicious malignancy, and 2 (8.7%) as probably benign. US-FNA showed diagnostic results specific for metastases in 21 of the 22 patients (95.5%) who had undergone US-FNA.

Conclusion:

Common US features in thyroid metastasis were hypoechogenicity, non-circumscribed margins, no calcifications, parallel shape, and the presence of suspicious cervical lymph nodes. US-FNA can be effectively used in the diagnosis of thyroid metastasis, preventing unnecessary surgery.

Analysis of tumor markers in cytological fluid obtained from computed tomography-guided needle aspiration biopsies for the diagnosis of ground-glass opacity pulmonary lesions

BACKGROUND

The purpose of this study was to assess whether analyses of tumor markers in cytological fluid can improve the performance of computed tomography (CT)-guided needle aspiration biopsy (NAB) for the diagnosis of ground-glass opacity (GGO) pulmonary lesions.

METHODS

Forty-two patients were prospectively enrolled for CT-guided NAB. Levels of cytokeratin 19 fragments (CYFRA 21-1) and carcinoembryonic antigen (CEA) from serum and cytological fluid were measured. The cutoff values of 3.3 ng/mL for CYFRA 21-1 and 5.0 ng/mL for CEA (threshold A) or thresholds by adding 2 standard deviations to the mean levels of markers found in patients without malignancy (threshold B) were used to identify malignancy. The sensitivity and area under the curve (AUC) of NAB alone were compared with those of NAB combined with serum or cytological tumor markers.

RESULTS

Among the 42 patients, 30 (71.4%) had malignant and 12 (28.6%) had benign lesions. For NAB alone, the sensitivity, specificity, and AUC for diagnosing GGO were 70.0%, 100%, and 0.850, respectively. The sensitivity and AUC increased significantly for NAB with cytological CYFRA 21-1 compared with NAB alone, using both thresholds (threshold A: 86.7%, P=.026 and .933, P=.016; threshold B: 93.3%, P=.008 and .925, P=.046).

CONCLUSIONS

Cytological fluid measurements of CYFRA 21-1 can improve the diagnostic performance of CT-guided NAB for GGO pulmonary lesions.

CT fluoroscopy-guided lung biopsy versus conventional CT-guided lung biopsy: a prospective controlled study to assess radiation doses and diagnostic performance

OBJECTIVE

We evaluated radiation doses, complication rates, and diagnostic accuracy for CT-guided percutaneous needle aspiration biopsy (NAB) procedures of pulmonary lesions performed with or without fluoroscopic guidance.

METHODS

A total of 142 patients were prospectively enrolled to receive CT-guided NAB with (Group I, n = 72) or without (Group II, n = 70) fluoroscopic guidance. Outcome measurements were patient and doctor radiation dose, and complication rate. Sensitivity, specificity and accuracy were calculated based on 123 NAB results.

RESULTS

The mean estimated effective patient radiation dose was 6.53 mSv in Group I and 2.72 mSv in Group II (p < 0.001). The mean estimated effective doctor dose was 0.054 mSv in Group I and 0.029 mSv in Group II (p < 0.001). The complication rate was significantly different between the two groups (13.4% versus 31.4%, p = 0.012). Sensitivity, specificity and accuracy for diagnosing pulmonary lesions were 97.8%, 100% and 98.4% in group I and 95.3%, 100% and 89.5% in group II (p > 0.05).

CONCLUSIONS

CT fluoroscopy-guided NAB of pulmonary lesions provides high diagnostic accuracy and can be performed with significantly fewer complications. However, radiation exposure to both patient and doctor were significantly higher than conventional CT-guided NAB.

In search of dialogue and discourse in applied clinical informatics

We present a model of applied clinical informatics in the context of medical informatics in general, across the domain of health sciences and the continuum of information technology development and its adoption into workflow. The distinct challenges of applied clinical informatics present an opportunity to improve efforts through collaboration of the growing number of physicians, health institutional leaders and other health workers in successfully implementing working systems. This journal will be a forum for discussion regarding approaches to design, implement, deploy and evaluate systems and importantly, how to present experiences in a way to maximize sharing of those experiences.

Challenges in reusing transactional data for daily documentation in neonatal intensive care

The reuse of transactional data for clinical documentation requires navigation of computational, institutional and adaptive barriers. We describe organizational and technical issues in developing and deploying a daily progress note tool in a tertiary neonatal intensive care unit that reuses and aggregates data from a commercial integrated clinical information system.

Application of a Medical Text Indexer to an online dermatology atlas

Clinical dermatology cases are presented as images and semi-structured text describing skin lesions and their relationships to disease. Metadata assignment to such cases is hampered by lack of a standardized dermatology vocabulary and facilitated methods for indexing legacy collections. In this pilot study descriptive clinical text from Dermatlas, a Web-based repository of dermatology cases, was indexed to Medical Subject Heading (MeSH) terms using the National Library of Medicine's Medical Text Indexer (MTI). The MTI is an automated text processing system that derives ranked lists of MeSH terms to describe the content of medical journal citations using knowledge from the Unified Medical Language System (UMLS) and from MEDLINE. For a representative, random sample of 50 Dermatlas cases, the MTI frequently derived MeSH indexing terms that matched expert-assigned terms for Diagnoses (88%), Lesion Types (72%), and Patient Characteristics (Gender and Age Groups, 62% and 84% respectively). This pilot demonstrates the potential for extending the MTI to automate indexing of clinical case presentations and for using MeSH to describe aspects of clinical dermatology.

Reducing the paper load: computer-based patient records

Physicians burdened with increasing paper work may find relief in computer-based patient records (CPR). CPRs may aid clinicians in the areas of billing, documentation, reporting, and data retrieval. Value-added features like decision support and event monitoring facilitate patient outcome, decrease health care costs and allow improved administration. The authors discuss obstacles in the use of computers in patient care with a focus on security, confidentiality, and Y2K.

Restricted natural language processing for case simulation tools

For Interactive Patient II, a multimedia case simulation designed to improve history-taking skills, we created a new natural language interface called GRASP (General Recognition and Analysis of Sentences and Phrases) that allows students to interact with the program at a higher level of realism. Requirements included the ability to handle ambiguous word senses and to match user questions/queries to unique Canonical Phrases, which are used to identify case findings in our knowledge database. In a simulation of fifty user queries, some of which contained ambiguous words, this tool was 96% accurate in identifying concepts.

Molecular biological characterization of enterovirus variant isolated from patients with aseptic meningitis

In Korea, there was a big outbreak of aseptic meningitis in 1993. Six clinical isolates of enterovirus were obtained from patients with aseptic meningitis and were identified as echovirus type 9 by serotyping with a pool of neutralizing antisera. For molecular characterization of the isolates, the nucleotide sequences of 5'-noncoding region (NCR), VP4, VP2, VP1, 2A and 2C regions of the isolates were compared with the corresponding regions of echovirus type 9 Hill and Barty strains. Unlike Hill strain, Barty strain contained a C-terminal extension to the capsid protein VP1 with an RGD (argnine-glycine-aspartic acid) motif. To determine whether similar structural features were present in our isolates, their nucleotide sequences including the VP1 region were analyzed. All isolates exhibited the VP1 extension with the RGD motif. We concluded the Korean isolates in the year of 1993 as the echovirus type 9 Barty strain although the isolates showed 15-20% nucleotide sequence differences in the several genomic regions.

Rapid subgrouping of nonpolio enterovirus associated with Aseptic Meningitis by RFLP (Restriction Fragment Length Polymorphism) assay

In Korea, there was a big outbreak of Aseptic Meningitis due to enterovirus infection in 1993. Since virus isolation and neutralizing tests are too laborious and time-consuming for the detection of enterovirus from clinical specimen, we have developed a new molecular identification method for rapid subgrouping of isolates from patients with aseptic meningitis. For the rapid subgrouping of isolates, RT-PCR (Reverse Transcription-Polymerase Chain Reaction) and RFLP (Restriction Fragment Length Polymorphism) assays were used. We have selected two oligonucleotide primers from the conserved 5'-UTR/VP2 and VP1 regions. A 652 bp (base pair) product was amplified from the 5'-UTR/VP2 region of reference viruses and the isolates. For the subgrouping of the isolates by RFLP assay, we have used 12 reference viruses (Echovirus, E6, E9, E11, E12, Coxsackievirus, CB1, CB3, CB4, CB5, Coxsackievirus, CA9, CA16, CA21, CA24), which are the common viral agents associated with aseptic meningitis. By using subgroup-specific restriction enzymes BsmAI, , HinP1I, and PleI, the isolates were classified into Echovirus subgroups. We have also shown that subgrouping of the isolates by RFLP assay based on the VP1 region is possible.

Utilization of a paediatric link collection by health professionals and laypersons

The Internet is an evolving resource for health-care information. However little information exists on providers' and other web patrons' usage of the 'medical' Internet. This study aims to characterize the users of a large paediatric link collection, describe their objectives and track their use of the information provided by the site. We utilized a paediatric link collection called the Pediatric Points of Interest (POI) and a combination of a questionnaire, unique user identifier and link-tracking system to collect data about POI patrons' demographics and Internet resource utilization. During a five week period, 5216 individuals visited the POI and requested 36,187 links. The majority of users had less than one year of Internet experience and were first-time visitors to the POI. More than 83% of users were from North America. Medical professionals were more likely to return to the POI during the study period and reported visiting the POI mainly for 'medical education', 'research', 'resource identification', and 'disease specific information'; they proceeded primarily to the resource categories 'Medical Institutions and Agencies' (32%) and 'Professional Education and Resources' (28%). Laypersons expressed the greatest interest in 'disease specific information' and 'patient education' and most frequently visited the category. 'Patient Education' (42%). On average, users were able to identify resources related to their stated goals within one level of searching. Health care providers and other web patrons are actively utilizing Internet sites to seek medical information and are able to identify resources with a minimum of searching.

Nucleotide sequencing of a part of the 5'-noncoding region of echovirus type 9 and rapid virus detection during the acute phase of aseptic meningitis

A part of the 5'-noncoding region of echovirus type 9 isolates was sequenced, and an attempt was made for rapid virus detection in clinical samples obtained from 22 subjects hospitalized with aseptic meningitis. The sequence identity of 440-bp products amplified from the region by RT-PCR was 87.7% between the standard echovirus type 9(Hill strain) and the isolates. Specific IgM antibodies to Hill strain were positive in 45.5% by immunofluorescent antibody staining of virus-infected cells. A high detection rate of PCR products was observed in cerebrospinal fluids (CSFs; 54.5%) at admission, and in peripheral mononuclear cells (PMCs; 72.7%) at the end of hospitalization. Viral genomes were detectable for 2 days in serum samples, and for 6 days in PMC samples after onset of disease. When specific IgM antibody titers were less than 1:40, the amplification rate of viral genome from serum samples was 50.0%. These results indicate that the combination of specific IgM determination and viral genome amplification from CSFs will be a rapid and reliable method for early diagnosis.

Genomic characterization of M and S RNA segments of hantaviruses isolated from bats

Genomic analysis of three Hantaan-like virus isolates from bats was performed. Cleavage patterns of reverse transcription (RT)-polymerase chain reaction (PCR) products and nucleotide sequences of G2 region of M RNA segment and N protein region of S RNA segment of the isolates were compared to that of Hantaan 76-118 strain. Genomic characteristics of the bat isolates were identical to that of Hantaan virus.

A new natural reservoir of hantavirus: isolation of hantaviruses from lung tissues of bats

Two species of bats were confirmed as new natural reservoirs of hantavirus. Antibodies to Hantaan virus were detected in 3.40% (23 of 677) of bats captured from 1989 to 1992 in Korea by the IFA technique. Areal distribution of immunofluorescent antibody were different, and seropositive rates were much high in sera of bats captured in summer (3.82%) and winter (5.82%). Viral antigens were observed in the lungs (3 of 16) and kidney (1 of 7). Two hantaviruses were isolated from lung tissues of E. serotinus and R. ferrum-equinum through a cell culture system, designated CUMC-92B8 and -92B48, respectively. Using Rous associated virus-2 reverse transcriptase-directed PCR and 2 oligonucleotide primer pairs, genomic sequences of the isolates were amplified. Amplified products of the isolates and reactivities to monoclonal antibodies very closely resembled those of Hantaan virus. These data suggest that the serotype of the isolates is closely related to Hantaan virus, and bats serve as reservoirs of hantavirus.