Evaluation of Computer-Aided Nodule Assessment and Risk Yield (CANARY) in Korean patients for prediction of invasiveness of ground-glass opacity nodule.

Differentiating the invasiveness of ground-glass nodules (GGN) is clinically important, and several institutions have attempted to develop their own solutions by using computed tomography images. The purpose of this study is to evaluate Computer-Aided Analysis of Risk Yield (CANARY), a validated virtual biopsy and risk-stratification machine-learning tool for lung adenocarcinomas, in a Korean patient population. To this end, a total of 380 GGNs from 360 patients who underwent pulmonary resection in a single institution were reviewed. Based on the Score Indicative of Lung Cancer Aggression (SILA), a quantitative indicator of CANARY analysis results, all of the GGNs were classified as "indolent" (atypical adenomatous hyperplasia, adenocarcinomas in situ, or minimally invasive adenocarcinoma) or "invasive" (invasive adenocarcinoma) and compared with the pathology reports. By considering the possibility of uneven class distribution, statistical analysis was performed on the 1) entire cohort and 2) randomly extracted six sets of class-balanced samples. For each trial, the optimal cutoff SILA was obtained from the receiver operating characteristic curve. The classification results were evaluated using several binary classification metrics. Of a total of 380 GGNs, the mean SILA for 65 (17.1%) indolent and 315 (82.9%) invasive lesions were 0.195±0.124 and 0.391±0.208 (p < 0.0001). The area under the curve (AUC) of each trial was 0.814 and 0.809, with an optimal threshold SILA of 0.229 for both. The macro F1-score and geometric mean were found to be 0.675 and 0.745 for the entire cohort, while both scored 0.741 in the class-equalized dataset. From these results, CANARY could be confirmed acceptable in classifying GGN for Korean patients after the cutoff SILA was calibrated. We found that adjusting the cutoff SILA is needed to use CANARY in other countries or races, and geometric mean could be more objective than F1-score or AUC in the binary classification of imbalanced data.

Cost-Effectiveness of Treatment Thresholds for Subsolid Pulmonary Nodules in CT Lung Cancer Screening.

Background Guidelines such as the Lung CT Screening Reporting and Data System (Lung-RADS) are available for determining when subsolid nodules should be treated within lung cancer screening programs, but they are based on expert opinion. Purpose To evaluate the cost-effectiveness of varying treatment thresholds for subsolid nodules within a lung cancer screening setting by using a simulation model. Materials and Methods A previously developed model simulated 10 million current and former smokers undergoing CT lung cancer screening who were assumed to have a ground-glass nodule (GGN) at baseline. Nodules were allowed to grow and to develop solid components over time according to a monthly cycle and lifetime horizon. Management strategies generated by varying treatment thresholds, including the solid component size and use of the Brock risk calculator, were tested. For each strategy, average U.S. costs and quality-adjusted life years (QALYs) gained per patient were computed, and the incremental cost-effectiveness ratios (ICERs) of those on the efficient frontier were calculated. One-way and probabilistic sensitivity analyses of results were performed by varying several relevant parameters, such as treatment costs or malignancy growth rates. Results Variants of the Lung-RADS guidelines that did not treat pure GGNs were cost-effective. Strategies based on the Brock risk calculator did not reach the efficient frontier. The strategy with the highest QALYs under a willingness-to-pay threshold of $100 000 per QALY included no treatment of GGNs and a threshold of 4-mm solid component size for treatment of subsolid nodules. This strategy yielded an ICER of $52 993 per QALY (95% CI: 44 407, 64 372). Probabilistic sensitivity analysis showed this was the optimal strategy under a range of parameter variations. Conclusion Treatment of pure ground-glass nodules was not cost-effective. Strategies that use modifications of the Lung CT Screening Reporting and Data System guidelines were cost-effective for treating part-solid nodules; an optimal threshold of 4 mm for the solid component yielded the most quality-adjusted life years. © RSNA, 2021 Online supplemental material is available for this article.

Low-cost, high-resolution imaging for detecting cervical precancer in medically-underserved areas of Texas.

OBJECTIVE: Cervical cancer rates in the United States have declined since the 1940's, however, cervical cancer incidence remains elevated in medically-underserved areas, especially in the Rio Grande Valley (RGV) along the Texas-Mexico border. High-resolution microendoscopy (HRME) is a low-cost, in vivo imaging technique that can identify high-grade precancerous cervical lesions (CIN2+) at the point-of-care. The goal of this study was to evaluate the performance of HRME in medically-underserved areas in Texas, comparing results to a tertiary academic medical center. METHODS: HRME was evaluated in five different outpatient clinical settings, two in Houston and three in the RGV, with medical providers of varying skill and training. Colposcopy, followed by HRME imaging, was performed on eligible women. The sensitivity and specificity of traditional colposcopy and colposcopy followed by HRME to detect CIN2+ were compared and HRME image quality was evaluated. RESULTS: 174 women (227 cervical sites) were included in the final analysis, with 12% (11% of cervical sites) diagnosed with CIN2+ on histopathology. On a per-site basis, a colposcopic impression of low-grade precancer or greater had a sensitivity of 84% and a specificity of 45% to detect CIN2+. While there was no significant difference in sensitivity (76%, p = 0.62), the specificity when using HRME was significantly higher than that of traditional colposcopy (56%, p = 0.01). There was no significant difference in HRME image quality between clinical sites (p = 0.77) or medical providers (p = 0.33). CONCLUSIONS: HRME imaging increased the specificity for detecting CIN2+ when compared to traditional colposcopy. HRME image quality remained consistent across different clinical settings.

Economic value of narrow-band imaging versus white light endoscopy for the diagnosis and surveillance of Barrett's esophagus: Cost-consequence model.

Barrett's esophagus (BE) is an abnormality arising from gastroesophageal reflux disease that can progressively evolve into a sequence of dysplasia and adenocarcinoma. Progression of Barrett's esophagus into dysplasia is monitored with endoscopic surveillance. The current surveillance standard requests random biopsies plus targeted biopsies of suspicious lesions under white-light endoscopy, known as the Seattle protocol. Recently, published evidence has shown that narrow-band imaging (NBI) can guide targeted biopsies to identify dysplasia and reduce the need for random biopsies. We aimed to assess the health economic implications of adopting NBI-guided targeted biopsy vs. the Seattle protocol from a National Health Service England perspective. A decision tree model was developed to undertake a cost-consequence analysis. The model estimated total costs (i.e. staff and overheads; histopathology; adverse events; capital equipment) and clinical implications of monitoring a cohort of patients with known/suspected BE, on an annual basis. In the simulation, BE patients (N = 161,657 at Year 1; estimated annual increase: +20%) entered the model every year and underwent esophageal endoscopy. After 7 years, the adoption of NBI with targeted biopsies resulted in cost reduction of £458.0 mln vs. HD-WLE with random biopsies (overall costs: £1,966.2 mln and £2,424.2 mln, respectively). The incremental investment on capital equipment to upgrade hospitals with NBI (+£68.3 mln) was offset by savings due to the reduction of histological examinations (-£505.2 mln). Reduction of biopsies also determined savings for avoided adverse events (-£21.1 mln). In the base-case analysis, the two techniques had the same accuracy (number of correctly identified cases: 1.934 mln), but NBI was safer than HD-WLE. Budget impact analysis and cost-effectiveness analyses confirmed the findings of the cost-consequence analysis. In conclusion, NBI-guided targeted biopsies was a cost-saving strategy for NHS England, compared to current practice for detection of dysplasia in patients with BE, whilst maintaining at least comparable health outcomes for patients.

Development of Algorithms for Automated Detection of Cervical Pre-Cancers With a Low-Cost, Point-of-Care, Pocket Colposcope.

GOAL: In this paper, we propose methods for (1) automatic feature extraction and classification for acetic acid and Lugol's iodine cervigrams and (2) methods for combining features/diagnosis of different contrasts in cervigrams for improved performance. METHODS: We developed algorithms to pre-process pathology-labeled cervigrams and extract simple but powerful color and textural-based features. The features were used to train a support vector machine model to classify cervigrams based on corresponding pathology for visual inspection with acetic acid, visual inspection with Lugol's iodine, and a combination of the two contrasts. RESULTS: The proposed framework achieved a sensitivity, specificity, and accuracy of 81.3%, 78.6%, and 80.0%, respectively, when used to distinguish cervical intraepithelial neoplasia (CIN+) relative to normal and benign tissues. This is superior to the average values achieved by three expert physicians on the same data set for discriminating normal/benign cases from CIN+ (77% sensitivity, 51% specificity, and 63% accuracy). CONCLUSION: The results suggest that utilizing simple color- and textural-based features from visual inspection with acetic acid and visual inspection with Lugol's iodine images may provide unbiased automation of cervigrams. SIGNIFICANCE: This would enable automated, expert-level diagnosis of cervical pre-cancer at the point of care.

Assessment of Barrett's esophagus and dysplasia with ultrahigh-speed volumetric en face and cross-sectional optical coherence tomography.

BACKGROUND: This study aimed to evaluate the use of ultrahigh-speed volumetric en face and cross-sectional optical coherence tomography (OCT) with micromotor catheters for the in vivo assessment of Barrett's esophagus and dysplasia. METHODS: 74 OCT datasets with correlated biopsy/endoscopic mucosal resection histology (49 nondysplastic Barrett's esophagus [NDBE], 25 neoplasia) were obtained from 14 patients with Barrett's esophagus and a history of dysplasia and 30 with NDBE. The associations between irregular mucosal patterns on en face OCT, absence of mucosal layering, surface signal > subsurface, and > 5 atypical glands on cross-sectional OCT vs. histology and treatment history were assessed by three blinded readers. RESULTS: Atypical glands under irregular mucosal patterns occurred in 75 % of neoplasia (96 % of treatment-naïve neoplasia) vs. 30 % of NDBE datasets (43 % of short- and 18 % of long-segment NDBE). Mucosal layering was absent in 35 % of neoplasia and 50 % of NDBE datasets, and surface signal > subsurface occurred in 29 % of neoplasia and 30 % of NDBE datasets. CONCLUSIONS: Atypical glands under irregular mucosal patterns are strongly associated with neoplasia, suggesting potential markers for dysplasia and a role in pathogenesis.

Narrow band imaging and serology in the assessment of premalignant gastric pathology.

BACKGROUND: Patient outcomes in gastric adenocarcinoma are poor due to late diagnosis. Detecting and treating at the premalignant stage has the potential to improve this. Helicobacter pylori is also a strong risk factor for this disease. AIMS: Primary aims were to assess the diagnostic accuracy of magnified narrow band imaging (NBI-Z) endoscopy and serology in detecting normal mucosa, H. pylori gastritis and gastric atrophy. Secondary aims were to compare the diagnostic accuracies of two classification systems using both NBI-Z and white light endoscopy with magnification (WLE-Z) and evaluate the inter-observer agreement. METHODS: Patients were prospectively recruited. Images of gastric mucosa were stored with histology and serum for IgG H. pylori and Pepsinogen (PG) I/II ELISAs. Blinded expert endoscopists agreed on mucosal pattern. Mucosal images and serological markers were compared with histology. Kappa statistics determined inter-observer variability for randomly allocated images among four experts and four non-experts. RESULTS: 116 patients were prospectively recruited. Diagnostic accuracy of NBI-Z for determining normal gastric mucosa was 0.87(95%CI 0.82-0.92), H. pylori gastritis 0.65(95%CI 0.55-0.75) and gastric atrophy 0.88(95%CI 0.81-0.94). NBI-Z was superior to serology at detecting gastric atrophy: NBI-Z gastric atrophy 0.88(95%CI 0.81-0.94) vs PGI/II ratio < 3 0.74(95%CI 0.62-0.85) p<.0001. Overall NBI-Z was superior to WLE-Z in detecting disease using two validated classifications. Inter-observer agreement was 0.63(95%CI 0.51-0.73). CONCLUSIONS: NBI-Z accurately detects changes in the GI mucosa which currently depend on histology. NBI-Z is useful in the detection of precancerous conditions, potentially improving patient outcomes with early intervention to prevent gastric cancer.

Tissue multifractality and hidden Markov model based integrated framework for optimum precancer detection.

We report the application of a hidden Markov model (HMM) on multifractal tissue optical properties derived via the Born approximation-based inverse light scattering method for effective discrimination of precancerous human cervical tissue sites from the normal ones. Two global fractal parameters, generalized Hurst exponent and the corresponding singularity spectrum width, computed by multifractal detrended fluctuation analysis (MFDFA), are used here as potential biomarkers. We develop a methodology that makes use of these multifractal parameters by integrating with different statistical classifiers like the HMM and support vector machine (SVM). It is shown that the MFDFA-HMM integrated model achieves significantly better discrimination between normal and different grades of cancer as compared to the MFDFA-SVM integrated model.

Vocal fold leukoplakia: incidence, management, and prevention.

PURPOSE OF REVIEW: The purpose of this article is to provide an update on English-language literature evaluating the current understanding of incidence, management, and prevention of vocal fold leukoplakia focusing on premalignancy. RECENT FINDINGS: Recent studies have continued to try to elucidate factors influencing recurrence and progression of dysplastic disease, though results vary. Although advanced diagnostic techniques have attempted to predict disease behavior, tissue diagnosis continues to be essential. Studies reinforce the necessity of removal of disease as the primary treatment, whereas use of photoangiolytic lasers via the ablative technique has increased, as has transition of some patients into the office-based settings for treatment. Although genetic and molecular testing may hold promise for predictive purposes, further study is necessary, and chemotherapy for recalcitrant disease continues to be an area of study with few case studies being reported. SUMMARY: Management of vocal fold leukoplakia continues to progress in terms of identification and treatment. Although many work to advance our knowledge in the field and push treatment strategies toward newer avenues, pathologic diagnosis, eradiation of disease on the basis of experience and skill, and close surveillance continue to be paramount.

Image assessment of Barrett's esophagus using the simplified narrow band imaging classification.

BACKGROUND: A simplified narrow band imaging (NBI) classification has been proposed with the objective of integrating multiple classifications of NBI surface patterns in Barrett's esophagus (BE). Little is known about the impact of the simplified NBI classification on the diagnosis of BE when using high-definition magnification endoscopy with NBI (HM-NBI). This study aimed to evaluate (a) the reproducibility of NBI surface patterns and predicted histology and (b) the diagnostic accuracy of interpreting HM-NBI images by using the simplified NBI classification. METHODS: Two hundred and forty-eight HM-NBI images from macroscopically normal areas in patients with BE were retrieved from endoscopy databases and randomized for review by four endoscopists (two experts, two non-experts). We evaluated inter- and intra-observer agreement of the interpretation of NBI surface patterns and the predicted histology (dysplasia vs. non-dysplasia), as calculated by using κ statistics, and diagnostic values of the prediction. RESULTS: The overall inter-observer agreements were substantial for mucosal pattern (κ = 0.73) and vascular pattern (κ = 0.71), and almost perfect for predicting dysplastic histology (κ = 0.80). The overall intra-observer agreements were almost perfect for mucosal (κ = 0.84) and vascular patterns (κ = 0.86), and predicting dysplastic histology (κ = 0.89). The mean accuracy in predicting dysplastic histology for all reviewers was 95 % (experts: 96.8 %, non-experts: 93.1 %). CONCLUSIONS: The simplified NBI classification has the potential to provide high diagnostic reproducibility and accuracy when using HM-NBI.

Quantitative assessment of pancreatic cancer precursor lesions in IHC-stained tissue with a tissue image analysis platform.

Tissue image analysis (tIA) is emerging as a powerful tool for quantifying biomarker expression and distribution in complex diseases and tissues. Pancreatic ductal adenocarcinoma (PDAC) develops in a highly complex and heterogeneous tissue environment and, generally, has a very poor prognosis. Early detection of PDAC is confounded by limited knowledge of the pre-neoplastic disease stages and limited methods to quantitatively assess disease heterogeneity. We sought to develop a tIA approach to assess the most common PDAC precursor lesions, pancreatic intraepithelial neoplasia (PanIN), in tissues from KrasLSL-G12D/+; Trp53LSL-R172H/+; Pdx-Cre (KPC) mice, a validated model of PDAC development. tIA profiling of training regions of PanIN and tumor microenvironment (TME) cells was utilized to guide identification of PanIN/TME tissue compartment stratification criteria. A custom CellMap algorithm implementing these criteria was applied to whole-slide images of KPC mice pancreata sections to quantify p53 and Ki-67 biomarker staining in each tissue compartment as a proof-of-concept for the algorithm platform. The algorithm robustly identified a higher percentage of p53-positive cells in PanIN lesions relative to the TME, whereas no difference was observed for Ki-67. Ki-67 expression was also quantified in a human pancreatic tissue sample available to demonstrate the translatability of the CellMap algorithm to human samples. Together, our data demonstrated the utility of CellMap to enable objective and quantitative assessments, across entire tissue sections, of PDAC precursor lesions in preclinical and clinical models of this disease to support efforts leading to novel insights into disease progression, diagnostic markers, and potential therapeutic targets.

Virtual gastrointestinal colonoscopy in combination with large bowel endoscopy: clinical application.

Although colorectal cancer (CRC) has no longer been the leading cancer killer worldwide for years with the exponential development in computed tomography (CT) or magnetic resonance imaging, and positron emission tomography/CT as well as virtual colonoscopy for early detection, the CRC related mortality is still high. The objective of CRC screening is to reduce the burden of CRC and thereby the morbidity and mortality rates of the disease. It is believed that this goal can be achieved by regularly screening the average-risk population, enabling the detection of cancer at early, curable stages, and polyps before they become cancerous. Large-scale screening with multimodality imaging approaches plays an important role in reaching that goal to detect polyps, Crohn's disease, ulcerative colitis and CRC in early stage. This article reviews kinds of presentative imaging procedures for various screening options and updates detecting, staging and re-staging of CRC patients for determining the optimal therapeutic method and forecasting the risk of CRC recurrence and the overall prognosis. The combination use of virtual colonoscopy and conventional endoscopy, advantages and limitations of these modalities are also discussed.

Risk for malignant and borderline ovarian neoplasms following basic preoperative evaluation by ultrasonography, ca125 level and age.

OBJECTIVE: To verify the basic preoperative evaluation in the discrimination between benign and malignant adnexal masses in our clinical practice. MATERIALS AND METHODS: Data were collected on the records of 636 women with adnexal masses who had undergone surgery either by open or endoscopic approaches. Those with obvious signs of malignancy, any history of cancer, emergency surgeries without basic evaluation were excluded. The preoperative features by age, ultrasound and serum Ca125 level were compared with final histopathological diagnosis at the four departments of the institution. These are the general gynecology (Group 1: exploratory laparotomy), the gynecologic endoscopy (Group 2: laparoscopy and adnexectomy), the gynecological oncology (Group 3: staging laparotomy) and the gynecologic endocrinology and infertility (Group 4: laparoscopy and cystectomy). RESULTS: There were simple and complex cyst rates of 22.3% and 77.2%, respectively. There were 86.3% benign, 4.1% (n:20) borderline ovarian tumor (BOT) and 6.4% (n:48) malignant lesions. There were 3 BOT and 9 ovarian cancers in Group 1 and one BOT and two ovarian cancer in the Group 2. During the surgery, 15 BOT (75%) and 37 ovarian cancer (77%) were detected in the Group 3, only one BOT was encountered in the Group 4. The risk of rate of unsuspected borderline or focally invasive ovarian cancer significantly increased by age, size, complex morphology and Ca125 (95% CI, OR=2.72, OR=6.60, OR=6.66 and OR=4.69, respectively). CONCLUSIONS: Basic preoperative evaluation by comprehensive ultrasound imaging combined with age and Ca125 level has proved highly accurate for prediction of unexpected malignancies. Neither novel markers nor new imaging techniques provide better information that allow clinicians to assess the feasibility of the planned surgery; consequently, the risk of inadvertent cyst rupture during laparoscopy may be significantly decreased in selected cases.

Assessment of hemodynamics in a rat model of liver cirrhosis with precancerous lesions using multislice spiral CT perfusion imaging.

RATIONALE AND OBJECTIVES: To develop an optimal scanning protocol for multislice spiral CT perfusion (CTP) imaging to evaluate hemodynamic changes in liver cirrhosis with diethylnitrosamine- (DEN-) induced precancerous lesions. MATERIALS AND METHODS: Male Wistar rats were randomly divided into the control group (n = 80) and the precancerous liver cirrhosis group (n = 40). The control group received saline injection and the liver cirrhosis group received 50 mg/kg DEN i.p. twice a week for 12 weeks. All animals underwent plain CT scanning, CTP, and contrast-enhanced CT scanning. Scanning parameters were optimized by adjusting the diatrizoate concentration, the flow rate, and the delivery time. The hemodynamics of both groups was further compared using optimized multislice spiral CTP imaging. RESULTS: High-quality CTP images were obtained with following parameters: 150 kV; 150 mAs; 5 mm thickness, 5 mm interval; pitch, 1; matrix, 512 × 512; and FOV, 9.6 cm. Compared to the control group, the liver cirrhosis group had a significantly increased value of the hepatic arterial fraction and the hepatic artery perfusion (P < 0.05) but significantly decreased hepatic portal perfusion and mean transit time (P < 0.05). CONCLUSION: Multislice spiral CTP imaging can be used to evaluate the hemodynamic changes in the rat model of liver cirrhosis with precancerous lesions.

Comparison of risk of malignancy index (RMI), CA125, CA 19-9, ultrasound score, and menopausal status in borderline ovarian tumor.

OBJECTIVE: The aim of this study was to assess the prognostic values of risk of malignancy index (RMI IV), ultrasound score, menopausal status, and serum CA125 and CA19-9 level in patients with borderline ovarian tumor (BOT). METHODS: Fifty women having borderline ovarian tumor (BOT) and 5O individuals with benign adnexal mass were enrolled in this retrospective study. The sensitivity, specificity, positive predictive values, negative predictive values and diagnostic accuracy of preoperative serum levels of the CA125 and CA19-9, ultrasound findings and menopausal status, and RMI IV were calculated for prediction of discrimination between BOTs and benign adnexal masses and the results were compared. RESULTS: The RMI IV was the best method for discrimination between BOTs and benign adnexal masses and was more accurate than the other parameters. When Receiver Operator Characteristic area under the curves for menopausal status was analyzed, serum CA 125 and CA19-9 level, ultrasound score, RMI IV(CA125), and RMI IV(CA19-9) were, 0.580, 0.625, 0.548, 0.694, 0.734 and 0.711, respectively. The best RMI IV cut-off was found to be 200 for discrimination of benign and BOT lesions. In the RMI formulation, replacing CA125 with CA19-9 didn't affect RMI IV sensitivity and specificity for discrimination. CONCLUSION: Compared to ultrasound, menopausal status, CA-125, CA19-9, the RMI IV was found to be the best predictive method for differentiation of BOTs from benign adnexal masses. RMI IV cut-off value of 200 is suitable for differentiation of benign and BOT's.

The positive predictive value of BI-RADS microcalcification descriptors and final assessment categories.

OBJECTIVE: The purpose of this article is to retrospectively assess the likelihood of malignancy of microcalcifications according to the BI-RADS descriptors in a digital mammography environment. MATERIALS AND METHODS: The study included 146 women with calcifications who underwent imaging-guided biopsy between April 2005 and July 2006. Digital mammograms procured before biopsy were analyzed independently by two breast imaging subspecialists blinded to biopsy results. Lesions described discordantly were settled by consensus. One of the radiologists provided a BI-RADS final assessment score. RESULTS: The overall positive predictive value of biopsies was 28.8%. The individual morphologic descriptors predicted the risk of malignancy as follows: fine linear/branching, 16 (70%) of 23 cases; fine pleomorphic, 14 (28%) of 50 cases; coarse heterogeneous, two (20%) of 10 cases; amorphous, 10 (20%) of 51 cases; and typically benign, zero (0%) of 12 cases. Fisher-Freeman-Halton exact testing showed statistical significance among morphology descriptors (p < 0.001) and distribution descriptors (p < 0.001). The positive predictive value for malignancy according to BI-RADS assessment categories were as follows: category 2, 0%; category 3, 0%; category 4A, 13%; category 4B, 36%; category 4C, 79%; and category 5, 100%. CONCLUSION: BI-RADS morphology and distribution descriptors can aid in assessing the risk of malignancy of microcalcifications detected on full-field digital mammography. The positive predictive value increased in successive BI-RADS categories (4A, 4B, and 4C), verifying that subdivision provides an improved assessment of suspicious microcalcifications in terms of likelihood of malignancy.

Perfusion computed tomographic assessment of early hepatocellular carcinoma in cirrhotic liver disease: initial observations.

OBJECTIVE: To prospectively assess perfusion computed tomography (CT) for evaluation of tumor vascularity of early hepatocellular carcinoma (HCC) in patients with cirrhosis. METHODS: The study cohort included 30 patients who had Child-Pugh class A or B liver cirrhosis and a single histopathologically confirmed HCC not exceeding 3 cm in diameter. All patients underwent perfusion CT study using a multidetector 16-slice CT. Four perfusion parameters were measured for the HCCs and cirrhotic liver parenchyma: hepatic perfusion (HP), blood volume (BV), arterial perfusion (AP), and time to peak (TTP). Perfusion parameters were described with quartile (qt) values of their distribution; univariate paired Wilcoxon signed rank test was used for statistical analysis. RESULTS: The values of perfusion parameters measured within tumor tissue were the following: HP (milliliters per 100 g per minute): median = 45.7 (first qt = 35.3; third qt = 61.3); BV (milliliters per 100 mg): median = 20.6 (first qt = 13.0; third qt = 27.6); AP (milliliters per minute): median = 44.2 (first qt = 36.7; third qt = 57.0); TTP (seconds): median = 18.7 (first q = 15.9; third qt = 24.0). Our data showed that HP, BV, and AP values were higher (P < 0.001), whereas TTP was lower (P < 0.001), in HCCs relative to the cirrhotic liver parenchyma. For all the CT perfusion parameters calculated, there was a significant difference between HCC and background cirrhotic liver. CONCLUSIONS: Preliminary results suggest that in patients with cirrhosis and early HCC, perfusion CT is a feasible technique for noninvasive assessment of tumor vascularity.

Microcalcification detection based on wavelet domain hidden markov tree model: study for inclusion to computer aided diagnostic prompting system.

In this paper we investigate the performance of statistical modeling of digital mammograms by means of wavelet domain hidden Markov trees for its inclusion to a computer-aided diagnostic prompting system. The system is designed for detecting clusters of microcalcifications. Their further discrimination as benign or malignant is to be done by radiologists. The model is used for segmenting images based on the maximum likelihood classifier enhanced by the weighting technique. Further classification incorporates spatial filtering for a single microcalcification (MC) and microcalcification cluster (MCC) detection. Contrast filtering applied for the digital database for screening mammography (DDSM) dataset prior to spatial filtering greatly improves the classification accuracy. For all MC clusters of 40 mammograms from the mini-MIAS database of Mammographic Image Analysis Society, 92.5%-100% of true positive cases can be detected under 2-3 false positives per image. For 150 cases of DDSM cases, the designed system is capable to detect up to 98% of true positives under 3.3% of false positive cases.

Consensus review: A method of assessment of calcifications that appropriately undergo a six-month follow-up.

RATIONALE AND OBJECTIVES: Breast calcifications seen on mammography may be associated with benign conditions or malignancies. Accurate characterization of these calcifications is crucial to providing optimal care that may spare women unnecessary biopsies and appropriately allow interval mammography. The purpose of this study is to determine if consensus characterization of calcifications by two breast imaging experts using standardized criteria can establish that follow-up is a safe option. MATERIALS AND METHODS: For this retrospective study, our breast imaging database was reviewed and the cases imaged between the years 1999 and 2001 were used to identify patients with calcifications who were recommended for a six-month follow-up or biopsy. All cases had been prospectively assessed by at least two expert breast imagers using standardized features to assess the findings before a recommendation for follow-up or a biopsy was made. A retrospective chart review examining the radiology reports was done to determine the percentage of women from each of the two groups who developed malignancies. RESULTS: Of 744 patients who had mammographically identified clusters of calcifications, 490 clusters (409 single and 81 multiple) were diagnosed as probably-benign, and a short-interval 6-month follow-up was recommended. Of these calcifications followed for three years, only two (0.5%) of the single clusters proved to be malignant, and malignancy was diagnosed at the 12-month follow-up examination. In both cases, the women were diagnosed with ductal carcinoma in situ (DCIS). Of 254 clusters recommended for biopsy, 242 (215 single and 27 multiple) underwent biopsy. A total of 70 cancers were diagnosed: 54 (77.1%) were DCIS and 16 (22.9%) were primary invasive mammary carcinoma (10 cases of invasive ductal carcinoma, 3 cases of invasive lobular carcinoma, 2 cases of invasive ductal carcinoma with DCIS, and one case of invasive mucinous carcinoma with DCIS). Twenty-nine percent of women who had a biopsy performed had calcifications associated with malignancy. In contrast, in the women whose calcifications were followed by mammography, only 0.5% went on to develop malignancies. CONCLUSION: Consensus review of calcifications by two breast imagers using standardized criteria is a safe follow-up option.

Clinical impact of conventional endosonography and endoscopic ultrasound-guided fine-needle aspiration in the assessment of patients with Barrett's esophagus and high-grade dysplasia or intramucosal carcinoma who have been referred for endoscopic ablation therapy.

BACKGROUND AND STUDY AIMS: Endoscopic mucosal resection and photodynamic therapy are exciting, minimally invasive curative techniques that represent an alternative to surgery in patients with Barrett's esophagus and high-grade dysplasia or intramucosal adenocarcinoma. However, there is lack of uniformity regarding which staging method should be used prior to therapy, and some investigators even question whether staging is required prior to ablation. We report our experience with a protocol of conventional endoscopic ultrasound staging prior to endoscopic therapy. PATIENTS AND METHODS: A total of 25 consecutive patients with a diagnosis of high-grade dysplasia or intramucosal adenocarcinoma in Barrett's esophagus who had been referred to the University of Chicago for staging in preparation for endoscopic therapy between March 2002 and November 2004 were included in the study. All 25 patients underwent repeat diagnostic endoscopy and conventional endosonography with a radial echo endoscope. Any suspicious lymph nodes that were detected were sampled using endoscopic ultrasound-guided fine-needle aspiration. RESULTS: Baseline pathology in the 25 patients (mean age 70, range 49-85) revealed high-grade dysplasia in 12 patients and intramucosal carcinoma in 13 patients. Five patients were found to have submucosal invasion on conventional endosonography. Seven patients had suspicious adenopathy, six regional (N1) and one metastatic to the celiac axis (M1a). Fine-needle aspiration confirmed malignancy in five of these seven patients. Based on these results, five patients (20%) were deemed to be unsuitable candidates for endoscopic therapy. CONCLUSIONS: By detecting unsuspected malignant lymphadenopathy, conventional endosonography and endoscopic ultrasound with fine-needle aspiration dramatically changed the course of management in 20% of patients referred for endoscopic therapy of Barrett's esophagus with high-grade dysplasia or intramucosal carcinoma. Based on our results, we believe that conventional endosonography and endoscopic ultrasound with fine-needle aspiration when nodal disease is present should be performed routinely in all patients referred for endoscopic therapy in this setting.