AI analytics can be used as imaging biomarkers for predicting invasive upgrade of ductal carcinoma in situ.

OBJECTIVES: To evaluate whether the quantitative abnormality scores provided by artificial intelligence (AI)-based computer-aided detection/diagnosis (CAD) for mammography interpretation can be used to predict invasive upgrade in ductal carcinoma in situ (DCIS) diagnosed on percutaneous biopsy. METHODS: Four hundred forty DCIS in 420 women (mean age, 52.8 years) diagnosed via percutaneous biopsy from January 2015 to December 2019 were included. Mammographic characteristics were assessed based on imaging features (mammographically occult, mass/asymmetry/distortion, calcifications only, and combined mass/asymmetry/distortion with calcifications) and BI-RADS assessments. Routine pre-biopsy 4-view digital mammograms were analyzed using AI-CAD to obtain abnormality scores (AI-CAD score, ranging 0-100%). Multivariable logistic regression was performed to identify independent predictive mammographic variables after adjusting for clinicopathological variables. A subgroup analysis was performed with mammographically detected DCIS. RESULTS: Of the 440 DCIS, 117 (26.6%) were upgraded to invasive cancer. Three hundred forty-one (77.5%) DCIS were detected on mammography. The multivariable analysis showed that combined features (odds ratio (OR): 2.225, p = 0.033), BI-RADS 4c or 5 assessments (OR: 2.473, p = 0.023 and OR: 5.190, p < 0.001, respectively), higher AI-CAD score (OR: 1.009, p = 0.007), AI-CAD score ≥ 50% (OR: 1.960, p = 0.017), and AI-CAD score ≥ 75% (OR: 2.306, p = 0.009) were independent predictors of invasive upgrade. In mammographically detected DCIS, combined features (OR: 2.194, p = 0.035), and higher AI-CAD score (OR: 1.008, p = 0.047) were significant predictors of invasive upgrade. CONCLUSION: The AI-CAD score was an independent predictor of invasive upgrade for DCIS. Higher AI-CAD scores, especially in the highest quartile of ≥ 75%, can be used as an objective imaging biomarker to predict invasive upgrade in DCIS diagnosed with percutaneous biopsy. CRITICAL RELEVANCE STATEMENT: Noninvasive imaging features including the quantitative results of AI-CAD for mammography interpretation were independent predictors of invasive upgrade in lesions initially diagnosed as ductal carcinoma in situ via percutaneous biopsy and therefore may help decide the direction of surgery before treatment. KEY POINTS: • Predicting ductal carcinoma in situ upgrade is important, yet there is a lack of conclusive non-invasive biomarkers. • AI-CAD scores-raw numbers, ≥ 50%, and ≥ 75%-predicted ductal carcinoma in situ upgrade independently. • Quantitative AI-CAD results may help predict ductal carcinoma in situ upgrade and guide patient management.

Learnability of Thyroid Nodule Assessment on Ultrasonography: Using a Big Data Set.

OBJECTIVE: The aims of the work described here were to evaluate the learnability of thyroid nodule assessment on ultrasonography (US) using a big data set of US images and to evaluate the diagnostic utilities of artificial intelligence computer-aided diagnosis (AI-CAD) used by readers with varying experience to differentiate benign and malignant thyroid nodules. METHODS: Six college freshmen independently studied the "learning set" composed of images of 13,560 thyroid nodules, and their diagnostic performance was evaluated after their daily learning sessions using the "test set" composed of images of 282 thyroid nodules. The diagnostic performance of two residents and an experienced radiologist was evaluated using the same "test set." After an initial diagnosis, all readers once again evaluated the "test set" with the assistance of AI-CAD. RESULTS: Diagnostic performance of almost all students increased after the learning program. Although the mean areas under the receiver operating characteristic curves (AUROCs) of residents and the experienced radiologist were significantly higher than those of students, the AUROCs of five of the six students did not differ significantly compared with that of the one resident. With the assistance of AI-CAD, sensitivity significantly increased in three students, specificity in one student, accuracy in four students and AUROC in four students. Diagnostic performance of the two residents and the experienced radiologist was better with the assistance of AI-CAD. CONCLUSION: A self-learning method using a big data set of US images has potential as an ancillary tool alongside traditional training methods. With the assistance of AI-CAD, the diagnostic performance of readers with varying experience in thyroid imaging could be further improved.

Comparison of Posttreatment Stability Between Mandibular Setback Surgery-Early and Conventional Surgery in Class III Patients: A 4.6-Year Follow-Up.

OBJECTIVES: This retrospective study aims to compare long-term stability between the mandibular setback surgery-early (MSE) approach, involving minimal orthodontics, and the mandibular setback conventional surgery (MCS) approach, involving sufficient orthodontics, in Class III patients with mandibular prognathism. METHODS: Among 210 patients who underwent orthognathic surgery, a total of 40 subjects were enrolled based on standardized inclusion criteria: only mandibular surgery, <5 mm setback difference between right and left of the mandible, orthodontics with fixed appliances, and more than 2 years of follow-up after treatment. These patients were allocated to the MSE (n = 20) and MCS groups (n = 20) according to the duration of presurgical orthodontics. Changes in cephalometric measurements were compared between the MSE and MCS groups before surgery (T0), 1 month after surgery (T1), at the end of treatment (T2), and posttreatment retention (T3). RESULTS: The MSE and MCS groups had a mean presurgical orthodontic duration of 2 and 9.5 months, respectively. From T1 to T2, the MSE group showed a significantly larger forward movement of the mandible than the MCS group (2.1 versus 0.7 mm; P < 0.001). In addition, from T2 to T3 (average 4.6 years), the MSE group presented anterior relapse of 0.6 mm in the mandible, but there were no statistically significant intergroup differences. CONCLUSION: Although the MSE group showed greater postsurgical forward mandibular relapse than the MCS group, the two groups exhibited similar skeletal and dental stability during the posttreatment retention.

Lidocaine intensifies the anti-osteogenic effect on inflammation-induced human dental pulp stem cells via mitogen-activated protein kinase inhibition.

Background/purpose: Human dental pulp stem cells (hDPSCs) are an emerging source of mesenchymal stem cells (MSCs) for bone tissue regeneration and engineering. In bone regeneration using transplanted MSCs, the extracellular environment or co-injected drugs can affect their success or failure. In this study, we investigated the effects and signaling mechanisms of lidocaine on osteogenic differentiation of hDPSCs after inducing inflammatory conditions with lipopolysaccharide (LPS) and tumor necrosis factor-alpha (TNF-α). Materials and methods: To investigate the effect of lidocaine on the osteogenic differentiation of LPS/TNF-α-treated hDPSCs, alkaline phosphatase (ALP) and Alizarin red S (ARS) staining were conducted. The expression of osteogenesis-related genes was assessed using quantitative real-time polymerase chain reaction and western blotting. The expression of mitogen-activated protein kinases was analyzed to evaluate the effect of lidocaine on osteogenic differentiation of LPS/TNF-α-treated hDPSCs. Results: Various concentrations of lidocaine (0.05, 0.2, and 1 mM) further decreased ALP and ARS staining of LPS/TNF-α-treated hDPSCs. Similarly, the mRNA and protein expression of osteogenesis-related genes was suppressed via lidocaine treatment in LPS/TNF-α-treated hDPSCs. Lidocaine treatment downregulated the protein expression of p-ERK and p-JNK in LPS/TNF-α-treated hDPSCs. Conclusion: Lidocaine intensified the inhibition of osteogenic differentiation on inflammation-induced hDPSCs by inhibiting the ERK and JNK signaling pathways. This in vitro study suggested that lidocaine may have an inhibitory effect on bone regeneration.

Adult-onset megacolon with focal hypoganglionosis: A detailed phenotyping and prospective cohort study.

BACKGROUND: In this prospective cohort study, we evaluated features of "adult-onset megacolon with focal hypoganglionosis." METHODS: We assessed the radiologic, endoscopic, and histopathologic phenotyping and treatment outcomes of 29 patients between 2017 and 2020. Data from community controls, consisting of 19,948 adults undergoing health screenings, were analyzed to identify risk factors. Experts reviewed clinical features and pathological specimens according to the London Classification for gastrointestinal neuromuscular pathology. KEY RESULTS: The median age of the patients with adult-onset megacolon with focal hypoganglionosis at symptom onset was 59 years (range, 32.0-74.9 years), with mean symptom onset only 1 year before diagnosis. All patients had focal stenotic regions with proximal bowel dilatation (mean diameter, 78.8 mm; 95% confidence interval [CI], 72-86). The comparison with community controls showed no obvious risk factors. Ten patients underwent surgery, and all exhibited significant hypoganglionosis: 5.4 myenteric ganglion cells/cm (interquartile range [IQR], 3.7-16.4) in the stenotic regions compared to 278 cells/cm (IQR, 190-338) in the proximal and 95 cells/cm (IQR, 45-213) in the distal colon. Hypoganglionosis was associated with CD3+ T cells along the myenteric plexus. Colectomy was associated with significant symptom improvement compared to medical treatment [change in the Global Bowel Satisfaction score, -5.4 points (surgery) vs. -0.3 points (medical treatment); p < 0.001]. CONCLUSIONS AND INFERENCES: Adult-onset megacolon with focal hypoganglionosis has distinct features characterized by hypoganglionosis due to inflammation. Bowel resection appears to benefit these patients.

Comparison of postoperative nausea and vomiting between Remimazolam and Propofol in Patients undergoing oral and maxillofacial surgery: a prospective Randomized Controlled Trial.

BACKGROUND: Remimazolam is a recently approved, ultra-short-acting benzodiazepine. However, few studies have investigated remimazolam in relation to postoperative nausea and vomiting (PONV). This study aimed to compare the effects of remimazolam and propofol on PONV in patients undergoing oral and maxillofacial surgery. METHODS: Patients (n = 206) aged 19-65 years who were scheduled for oral and maxillofacial surgery were randomized into two groups, the remimazolam (R) and propofol group (P). In the R group (n = 94), remimazolam was used to induce anesthesia at 12 mg/kg/h and to maintain anesthesia at 1-2 mg/kg/h. In the P group (n = 95), anesthesia was induced and maintained with propofol (target effect-site concentration: 3-5 µg/ml). In both groups, remifentanil was administered at a target effect-site concentration of 2.5-4 ng/ml. The primary outcome was the overall incidence of PONV during the first 24 h after surgery. Secondary outcomes included the severity of nausea, use of rescue antiemetics, severity of postoperative pain, use of rescue analgesia, and quality of recovery. RESULTS: The incidence of PONV during the first 24 h after surgery was 11.7% and 10.5% in the R group and P group, respectively, and there was no significant difference in the severity of nausea (P > 0.05). Ten patients in the R group and ten patients in the P group required rescue antiemetics during the first 24 h after surgery (P = 0.98). No inter-group differences were observed in terms of postoperative pain score, use of rescue analgesia, and quality of recovery (P > 0.05). CONCLUSIONS: In this study, remimazolam did not increase the incidence and severity of PONV compared with propofol. TRIAL REGISTRATION: KCT0006965, Clinical Research Information Service (CRIS), Republic of Korea. Registration date: 26/01/2022.

Lidocaine inhibits osteogenic differentiation of human dental pulp stem cells in vitro.

OBJECTIVE: Lidocaine is an amide local anaesthetic commonly used for pain control, however, few studies have investigated the effect of lidocaine on the osteogenic differentiation of human dental pulp stem cells (HDPSCs). The present study aimed to determine the effect of lidocaine on HDPSC viability and osteogenic differentiation. METHODS: HDPSCs were incubated with 0, 0.05, 0.2, 0.5, and 1 mM lidocaine for 24, 48 and 72 h, after which, MTT assays were performed. HDPSCs cultured with the above lidocaine concentrations and osteogenic differentiation medium for 7 and 14 days were stained for alkaline phosphatase (ALP). Protein and mRNA levels of relevant osteogenic factors (bone morphogenetic protein-2 [BMP-2] and runt-related transcription factor 2 [RUNX2]) were examined using western blotting and real-time reverse-transcription polymerase chain reaction, respectively. RESULTS: Lidocaine did not affect the viability of HDPSCs, however, lidocaine reduced ALP activity in HDPSCs. Levels of ALP, BMP-2, and RUNX2 mRNA were reduced with lidocaine, and levels of BMP-2 and RUNX2 proteins were decreased, versus controls. CONCLUSIONS: Lidocaine inhibits osteogenic differentiation markers in HDPSCs in vitro, even at low concentrations, without cytotoxicity. This study suggests that lidocaine may inhibit osteogenic differentiation in HDPSC-mediated regenerative medicine, including pulp regeneration and repair.

The Potential Application of Human Gingival Fibroblast-Conditioned Media in Pulp Regeneration: An In Vitro Study.

Regenerative endodontic treatment based on tissue engineering has recently gained interest in contemporary restorative dentistry. However, low survival rates and poor potential differentiation of stem cells could undermine the success rate of pulp regenerative therapy. Human gingival fibroblast-conditioned medium (hGF-CM) has been considered a potential therapy for tissue regeneration due to its stability in maintaining multiple factors essential for tissue regeneration compared to live cell transplantation. This study aimed to investigate the potency of hGF-CM on stem cells from human dental pulp (DPSC) in pulp regeneration. A series of experiments confirmed that hGF-CM contributes to a significant increase in proliferation, migration capability, and cell viability of DPSC after H2O2 exposure. Moreover, it has been proved to facilitate the odontogenic differentiation of DPSC via qRT-PCR, ALP (alkaline phosphatase), and ARS (Alizarin Red S) staining. It has been discovered that such highly upregulated odontogenesis is related to certain types of ECM proteins (collagen and laminin) from hGF-CM via proteomics. In addition, it is found that the ERK pathway is a key mechanism via inhibition assay based on RNA-seq result. These findings demonstrate that hGF-CM could be beneficial biomolecules for pulp regeneration.

Atypical Manifestation of Primary Hepatocellular Carcinoma and Hepatic Malignancy Mimicking Lesions.

Hepatocellular carcinoma (HCC) can be diagnosed noninvasively on multiphasic CT and MRI based on its distinctive imaging findings. These features include arterial phase hyperenhancement and washout on portal or delayed phase images. However, radiologists face significant diagnostic challenges because some HCCs exhibit atypical imaging characteristics. In addition to many HCC-mimicking lesions, such as arterioportal shunts, combined HCC-cholangiocarcinoma, intrahepatic cholangiocarcinoma, and hemangioma present a challenge for radiologists in actual clinical practice. The ability to distinguish HCCs from mimickers on initial imaging examinations is crucial for appropriate management and treatment decisions. Therefore, this pictorial review presents the imaging findings of atypical HCCs and HCCs mimicking malignant and benign lesions and discusses important clues that may help narrow down the differential diagnosis.

Propofol protects against lipopolysaccharide-induced inflammatory response in human amnion-derived WISH cells.

Background: Nonobstetric surgery is sometimes required during pregnancy, and neck abscess or facial bone fracture surgery cannot be postponed in pregnant women. However, dental surgery can be stressful and can cause inflammation, and the inflammatory response is a well-known major cause of preterm labor. Propofol is an intravenous anesthetic commonly used for general anesthesia and sedation. Studies investigating the effect of propofol on human amnion are rare. The current study investigated the effects of propofol on lipopolysaccharide (LPS)-induced inflammatory responses in human amnion-derived WISH cells. Methods: WISH cells were exposed to LPS for 24 h and co-treated with various concentrations of propofol (0.01-1 µg/ml). Cell viability was measured using the MTT assay. Nitric oxide (NO) production was analyzed using a microassay based on the Griess reaction. The protein expression of cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE 2), p38, and phospho-p38 was analyzed using western blotting. Results: Propofol did not affect the viability and NO production of WISH cells. Co-treatment with LPS and propofol reduced COX-2 and PGE2 protein expression and inhibited p38 phosphorylation in WISH cells. Conclusion: Propofol does not affect the viability of WISH cells and inhibits LPS-induced expression of inflammatory factors. The inhibitory effect of propofol on inflammatory factor expression is likely mediated by the inhibition of p38 activation.

[Prediction of Helicobacter pylori Infection by Endoscopic Severity of Erythematous/exudative Gastritis in Asymptomatic Adults].

Background/Aims: Helicobacter pylori (H. pylori) infection highly correlates with erythematous/exudative gastritis, which is one of the endoscopic findings of the Sydney classification system. The present study aimed to evaluate the association between endoscopic severity of erythematous/exudative gastritis and H. pylori infection. Methods: We prospectively enrolled asymptomatic adults who were diagnosed with erythematous/exudative gastritis during screening esophagogastroduodenoscopy. A rapid urease test was performed in all participants to diagnose H. pylori infection. The severity of erythematous/exudative gastritis was determined based on the Sydney classification system. Two investigators independently evaluated the endoscopic findings. The primary endpoint was H. pylori infection rate according to the severity of erythematous/exudative gastritis (mild vs. moderate-to-severe). Results: A total of 177 patients with erythematous/exudative gastritis were included. The rate of H. pylori infection was 86.4% in all patients. Of 177 included patients, 78 were at mild degree, 48 were at moderate degree, and 51 were at severe degree. The inter-observer variation was 4.6% and kappa value was 0.593. H. pylori infection rate was similar between patients with mild erythematous/exudative gastritis and those with moderate-to-severe erythematous/exudative gastritis (91.0% vs. 82.8%, p=0.115). Even after adjusting potential confounding variables, the severity of erythematous/exudative gastritis was not associated with H. pylori infection rate. Conclusions: H. pylori infection is commonly observed in patients with erythematous/exudative gastritis. However, the severity of erythematous/exudative gastritis is not associated with H. pylori infection rate.

Chemically-induced osteogenic cells for bone tissue engineering and disease modeling.

Cell reprogramming can satisfy the demands of obtaining specific cell types for applications such as tissue regeneration and disease modeling. Here we report the reprogramming of human fibroblasts to produce chemically-induced osteogenic cells (ciOG), and explore the potential uses of ciOG in bone repair and disease treatment. A chemical cocktail of RepSox, forskolin, and phenamil was used for osteogenic induction of fibroblasts by activation of RUNX2 expression. Following a maturation, the cells differentiated toward an osteoblast phenotype that produced mineralized nodules. Bulk and single-cell RNA sequencing identified a distinct ciOG population. ciOG formed mineralized tissue in an ectopic site of immunodeficiency mice, unlike the original fibroblasts. Osteogenic reprogramming was modulated under engineered culture substrates. When generated on a nanofiber substrate ciOG accelerated bone matrix formation in a calvarial defect, indicating that the engineered biomaterial promotes the osteogenic capacity of ciOG in vivo. Furthermore, the ciOG platform recapitulated the genetic bone diseases Proteus syndrome and osteogenesis imperfecta, allowing candidate drug testing. The reprogramming of human fibroblasts into osteogenic cells with a chemical cocktail thus provides a source of specialized cells for use in bone tissue engineering and disease modeling.

Hyperelastic, shape-memorable, and ultra-cell-adhesive degradable polycaprolactone-polyurethane copolymer for tissue regeneration.

Novel polycaprolactone-based polyurethane (PCL-PU) copolymers with hyperelasticity, shape-memory, and ultra-cell-adhesion properties are reported as clinically applicable tissue-regenerative biomaterials. New isosorbide derivatives (propoxylated or ethoxylated ones) were developed to improve mechanical properties by enhanced reactivity in copolymer synthesis compared to the original isosorbide. Optimized PCL-PU with propoxylated isosorbide exhibited notable mechanical performance (50 MPa tensile strength and 1150% elongation with hyperelasticity under cyclic load). The shape-memory effect was also revealed in different forms (film, thread, and 3D scaffold) with 40%-80% recovery in tension or compression mode after plastic deformation. The ultra-cell-adhesive property was proven in various cell types which were reasoned to involve the heat shock protein-mediated integrin (α5 and αV) activation, as analyzed by RNA sequencing and inhibition tests. After the tissue regenerative potential (muscle and bone) was confirmed by the myogenic and osteogenic responses in vitro, biodegradability, compatible in vivo tissue response, and healing capacity were investigated with in vivo shape-memorable behavior. The currently exploited PCL-PU, with its multifunctional (hyperelastic, shape-memorable, ultra-cell-adhesive, and degradable) nature and biocompatibility, is considered a potential tissue-regenerative biomaterial, especially for minimally invasive surgery that requires small incisions to approach large defects with excellent regeneration capacity.

Dexmedetomidine and LPS co-treatment attenuates inflammatory response on WISH cells via inhibition of p38/NF-κB signaling pathway.

Background: Inflammatory dental diseases that occur during pregnancy can cause preterm labor and/or intrauterine growth restriction. Therefore, proactive treatment of dental diseases is necessary during pregnancy. Dexmedetomidine (DEX) is a widely used sedative in the dental field, but research on the effect of DEX on pregnancy is currently insufficient. In this study, we investigated the effects of co-treatment with DEX and lipopolysaccharide (LPS) on inflammatory responses in human amnion-derived WISH cells. Methods: Human amnion-derived WISH cells were treated with 0.001, 0.01, 0.1, and 1 µg/mL DEX with 1 µg/mL LPS for 24 h. Cytotoxicity of WISH cells was evaluated by 3-(4,5-dimethylthiazol)-2,5-diphenyltetrazolium bromide (MTT) assay. The protein expression of cyclooxygenase-2 (COX-2), prostaglandin E2 (PGE2), p38, and nuclear factor kappa B (NF-κB) was examined by western blot analysis. The mRNA expression of pro-inflammatory cytokines such as interleukin (IL)-1ß and tumor necrosis factor (TNF)-α was analyzed by real-time quantitative polymerase chain reaction. Results: Co-treatment with DEX and LPS showed no cytotoxicity in the WISH cells. The mRNA expression of IL-1ß and TNF-α decreased after co-treatment with DEX and LPS. DEX and LPS co-treatment decreased the protein expression of COX-2, PGE2, phospho-p38, and phospho-NF-κB in WISH cells. Conclusion: Co-treatment with DEX and LPS suppressed the expression of COX-2 and PGE2, as well as pro-inflammatory cytokines such as IL-1ß and TNF-α in WISH cells. In addition, the anti-inflammatory effect of DEX and LPS co-treatment was mediated by the inhibition of p38/NF-κB activation.

Differing benefits of artificial intelligence-based computer-aided diagnosis for breast US according to workflow and experience level.

PURPOSE: This study evaluated how artificial intelligence-based computer-assisted diagnosis (AICAD) for breast ultrasonography (US) influences diagnostic performance and agreement between radiologists with varying experience levels in different workflows. METHODS: Images of 492 breast lesions (200 malignant and 292 benign masses) in 472 women taken from April 2017 to June 2018 were included. Six radiologists (three inexperienced [<1 year of experience] and three experienced [10-15 years of experience]) individually reviewed US images with and without the aid of AI-CAD, first sequentially and then simultaneously. Diagnostic performance and interobserver agreement were calculated and compared between radiologists and AI-CAD. RESULTS: After implementing AI-CAD, the specificity, positive predictive value (PPV), and accuracy significantly improved, regardless of experience and workflow (all P<0.001, respectively). The overall area under the receiver operating characteristic curve significantly increased in simultaneous reading, but only for inexperienced radiologists. The agreement for Breast Imaging Reporting and Database System (BI-RADS) descriptors generally increased when AI-CAD was used (κ=0.29-0.63 to 0.35-0.73). Inexperienced radiologists tended to concede to AI-CAD results more easily than experienced radiologists, especially in simultaneous reading (P<0.001). The conversion rates for final assessment changes from BI-RADS 2 or 3 to BI-RADS higher than 4a or vice versa were also significantly higher in simultaneous reading than sequential reading (overall, 15.8% and 6.2%, respectively; P<0.001) for both inexperienced and experienced radiologists. CONCLUSION: Using AI-CAD to interpret breast US improved the specificity, PPV, and accuracy of radiologists regardless of experience level. AI-CAD may work better in simultaneous reading to improve diagnostic performance and agreement between radiologists, especially for inexperienced radiologists.

AI-CAD for differentiating lesions presenting as calcifications only on mammography: outcome analysis incorporating the ACR BI-RADS descriptors for calcifications.

OBJECTIVES: To evaluate how AI-CAD triages calcifications and to compare its performance to an experienced breast radiologist. METHODS: Among routine mammography performed between June 2016 and May 2018, 535 lesions detected as calcifications only on mammography in 500 women (mean age, 48.8 years) that were additionally interpreted with additional magnification views were included in this study. One dedicated breast radiologist retrospectively reviewed the magnification mammograms to assess morphology, distribution, and final assessment category according to ACR BI-RADS. AI-CAD analyzed routine mammograms providing AI-CAD marks and corresponding AI-CAD scores (ranging from 0 to 100%), for which values ≥ 10% were considered positive. Ground truth in terms of malignancy or benignity was confirmed with a histopathologic diagnosis or at least 1 year of imaging follow - up. RESULTS: Of the 535 calcifications, 215 (40.2%) were malignant. Calcifications with positive AI-CAD scores showed significantly higher PPVs compared to calcifications with negative scores for all morphology (all p < 0.05). PPVs were significantly higher in calcifications with positive AI-CAD scores compared to those with negative scores for BI-RADS 3, 4a, or 4b assessments (all p < 0.05). AI-CAD and the experienced radiologist did not show significant difference in diagnostic performance; sensitivity 92.1% vs 95.4% (p = 0.125), specificity 71.9% vs 72.5% (p = 0.842), and accuracy 80.0% vs 81.7% (p = 0.413). CONCLUSION: Among calcifications with same morphology or BI-RADS assessment, those with positive AI-CAD scores had significantly higher PPVs. AI-CAD showed similar diagnostic performances to the experienced radiologist for calcifications detected on mammography. KEY POINTS: • Among calcifications with same morphology or BI-RADS assessment, those with positive AI-CAD scores had significantly higher PPVs. • AI-CAD showed similar diagnostic performance to an experienced radiologist in assessing lesions detected as calcifications only on mammography. • Among malignant calcifications, calcifications with positive AI-CAD scores showed higher rates of invasive cancers than calcifications with negative scores (all p > 0.05).

Reevaluation of the expanded indications in undifferentiated early gastric cancer for endoscopic submucosal dissection.

BACKGROUND: Although the criteria for the indication of endoscopic submucosal dissection (ESD) for undifferentiated early gastric cancer (UD-EGC) have been recently proposed, accumulating reports on the non-negligible rate of lymph node metastasis (LNM) after indicated ESD raise questions on the reliability of the current criteria. AIM: To investigate the prevalence and risk factors of LNM in UD-EGC cases meeting the expanded indication for ESD. METHODS: We retrospectively reviewed 4780 UD-EGC cases that underwent surgical resection between January 2008 and February 2019 at Asan Medical Center, a tertiary university hospital in Korea. To identify the risk factors of LNM of UD-EGC meeting the expanded criteria for ESD, we performed a case-control study by matching the cases with LNM to those without at a ratio of 1:4. We reviewed the clinical, endoscopic, and histologic features of the cases to identify features with a significant difference according to the presence of LNM. Univariate and multivariate logistic regression analyses were performed to estimate the odds ratios (ORs). RESULTS: Of the 4780 UD-EGC cases, 1240 (25.9%) were identified to meet the expanded indication for ESD. Of the 1240 cases, 14 (1.1%) cases had LNM. Among the various clinical, endoscopic, and histopathological features that were evaluated, mixed histology (tumors consisting of 10%-90% of signet ring cells) had a marginally significant association (P = 0.059) with the risk of LNM. Moreover, diffuse blurring of the muscularis mucosae (MM) underneath the tumorous epithelium, a previously unrecognized histologic feature, had a significant association with the absence of LNM (P = 0.028). Multivariate logistic regression analysis showed that the blurring of MM was the only explanatory variable significantly associated with a reduced risk of LNM (OR: 0.12, 95%CI: 0.02-0.95; P = 0.045). CONCLUSION: The risk of LNM is higher than expected when using the current expanded indication for UD-EGC. Histological evaluation could provide useful clues for reducing the risk of LNM.

Sessile serrated lesions in patients with adenoma on index colonoscopy do not increase metachronous advanced adenoma risk.

OBJECTIVES: Post-polypectomy surveillance intervals should be determined based on index colonoscopy findings. However, the risk of metachronous lesions, resulting from the coexistence of adenoma and sessile serrated lesions (SSLs), has rarely been addressed. We evaluated the impact of synchronous SSL on the risk of metachronous lesions within similar adenoma risk groups. METHODS: We retrieved individuals with one or more adenomas on index colonoscopy in a single-center retrospective cohort and stratified them into four groups depending on the presence of SSL and low-risk/high-risk adenoma (LRA/HRA). Participants who underwent surveillance colonoscopies at least 12 months apart were included. We compared the risks of metachronous lesions including HRA, advanced adenoma (AA), or SSL within similar adenoma risk groups according to the presence of SSL. RESULTS: Overall 4493 individuals were included in the analysis. The risk of metachronous HRA/AA was not significantly higher in the adenoma with SSL group compared with the adenoma without SSL group, irrespective of LRA (HRA, 6/86 vs. 231/3297, P = 1.00; AA, 0/86 vs. 52/3297, P = 0.64) or HRA (HRA, 11/64 vs. 240/1046, P = 0.36; AA, 3/64 vs. 51/1046, P = 1.00). However, the risk of metachronous SSL in individuals with synchronous SSL was higher than that in those without SSL for both LRA (15/86 vs. 161/3297, P < 0.001) and HRA groups (11/64 vs. 61/1046, P = 0.002). CONCLUSION: The presence of synchronous SSL did not increase the risk of metachronous HRA/AA, compared with isolated adenoma, but increased the risk of metachronous SSL.

The Influence of Face Shields on the Quality of Colonoscopy in the Era of the COVID-19 Pandemic.

Background/Aims: The worldwide coronavirus disease 2019 pandemic has led endoscopists to use personal protective equipment (PPE) for infection prevention. This study aimed to investigate whether wearing a face shield as PPE affects the quality of colonoscopy. Methods: We reviewed the medical records and colonoscopy findings of patients who underwent colonoscopies at Asan Medical Center, Korea from March 10 to May 31, 2020. The colonoscopies in this study were performed by five gastroenterology fellows and four expert endoscopists. We compared colonoscopy quality indicators, such as withdrawal time, adenoma detection rate (ADR), mean number of adenomas per colonoscopy (APC), polypectomy time, and polypectomy adverse events, both before and after face shields were added as PPE on April 13, 2020. Results: Of the 1,344 colonoscopies analyzed, 715 and 629 were performed before and after the introduction of face shields, respectively. The median withdrawal time was similar between the face shield and no-face shield groups (8.72 minutes vs 8.68 minutes, p=0.816), as was the ADR (41.5% vs 39.8%, p=0.605) and APC (0.72 vs 0.77, p=0.510). Polypectomy-associated quality indicators, such as polypectomy time and polypectomy adverse events were also not different between the groups. Quality indicators were not different between the face shield and no-face shield groups of gastroenterology fellows, or of expert endoscopists. Conclusions: Colonoscopy performance was not unfavorably affected by the use of a face shield. PPE, including face shields, can be recommended without a concern about colonoscopy quality deterioration.

Development of colon cancer in a patient with longstanding colonic diffuse ganglioneuromatosis: a case report.

Colonic diffuse ganglioneuromatosis is an extremely rare disease in which multiple tumors derived from the ganglion cells, nerve fibers, and supporting cells are distributed in the colon. It is generally considered to be a benign neoplastic condition and is occasionally associated with rare hereditary conditions such as neurofibromatosis type I or multiple endocrine neoplasia type 2B. Here, we report a case of a patient in whom colon cancer developed 12 years after the initial diagnosis of colonic diffuse ganglioneuromatosis, which suggests a possible association between colonic diffuse ganglioneuromatosis and colorectal cancer.