SUMMARY Purpose: To compare the ultrasound results of thyroid nodules in the application of EU-TIRADS, K-TIRADS, ACR-TIRADS systems with post-operative histological results. To compare diagnostic values of the three TIRADS systems. Material and methods: This is a cross-sectional study with convenient sampling. We recruited thyroid nodules that were performed pre-operative ultrasound (applied EU-TIRADS, K-TIRADS, ACRTIRADS systems) and removal surgery in Hue University of Medicine and Pharmacy Hospital between September 2019 and July 2020. Results: 138 thyroid nodules of 122 patients were enrolled. The malignancy rate was 22.5%. The majority of the lesions were classified as EU-TIRADS 3 (47.8%), K-TIRADS 3 (47.8%) và ACR-TIRADS 2 (38.4%.). The AUC of the EU-TIRADS, K-TIRADS và ACR-TIRADS systems were 0.957, 0.951 and 0.956, respectively. Among the three systems, EU-TIRADS had the highest sensitivity (Se) and negative predictive value (NPV) (100%) while its specificity (Sp), positive predictive value (PPV) and accuracy (Acc) for malignancy were lowest. K-TIRADS showed the best Sp, PPV and Ac (97.2%; 89.7% and 94.2%, respectively) and the lowest other values. Conclusion: The ability to distinguish between the malignant thyroid nodules and the benign ones of the three TIRADS systems was at a very good level. EU-TIRADS showed the most effective diagnostic performance in Se and NPV, while K-TIRADS yielded the best Sp, PPV and Acc. Key words: thyroid nodules, diagnostic values, EU-TIRADS, K-TIRADS, ACR-TIRADS.

Covid-19 (coronavirus disease 19) đang là một trong những thách thức lớn nhất cho thế giới trong thời điểm hiện tại. Những tác động của coronavirus (SARS-CoV-2) không chỉ đơn thuần lên sức khỏe, mà còn ảnh hưởng nghiêm trọng đến kinh tế và cuộc sống của người dân trên toàn cầu. Một vài nước đã thông báo rằng họ đang trải phải qua một trong những tình huống tồi tệ nhất trong hơn 100 năm vừa qua.

SUMMARY Objective: To determine the value of ultrasound in the diagnosis of thyroid cancer. Subjects and methods: A cross-sectional descriptive study on 98 patients with thyroid nodules who came for treatment at the Military Institute of Medical Radiology and Oncology, from April 2020 to March 2021. Results: The size of malignant nodules was mainly less than 2cm. Thyroid cancer lesions were mainly characterized by highly hypoechoic on ultrasound (61.19%). Thyroid cancer nodules had taller-than-wide feature (Sensitivity: 76.12%; specificity: 86.96%; positive predictive value: 89.47%; negative predictive value: 71.43%; accuracy: 80.53%.); irregular border feature (sensitivity: 98.51%; specificity: 86.96%; positive predictive value: 91.67%; negative predictive value: 97.56%; accuracy: 93.81%); microcalcification characteristics (sensitivity: 73.13%; specificity: 91.30%; positive predictive value: 92.45%; negative predictive value: 70.00%; accuracy: 80,53%). TIRADS value in thyroid cancer diagnosis with sensitivity: 94.03%; specificity: 86.96%; positive predictive value: 91.30%; negative predictive value: 90.91%; Accuracy: 91.15%. Conclusion: The features of hypoechoic nodules, taller-than-wide shape, irregular border, microcalcification characteristics, and TIRADS 4, TIRADS 5 scores had high prognostic value for thyroid cancer. Keywords: Ultrasound, thyroid cancer.

SUMMARY Objectives: Describe the characteristics of ultrasound images, computed tomography, angiography and results of chemoembolization in patients with HCC under 40 years old at the Radiology Center of Bach Mai Hospital. Methods: A cross-sectional study was carried out on 25 patients with a confirmed HCC who treated chemoembolization at the Radiology Center - Bach Mai Hospital from August 2018 to August 2021. Results: On 2-dimensional ultrasound, the majority of HCC tumors had hypoechoic and mixed sound images (72%) and increased angiogenesis on color Doppler ultrasound, reaching 68.0%. On computed tomography images, tumor density decreased 64% and increased angiogenesis 68.0%. Tumors of HCC have increased angiogenesis on angiography, reaching 92%. After treatment AFP tends to decrease in the first 6 months, then increase in the 9th month. Bilirubin tends to decrease in the first 3 months, then increase at 6 and 9 months. Tumor size tends to decrease at 1, 3 and increase at 6, 9 months. Median survival was 13 months with interquartile range [5.5 ÷ 22], the longest survival time with continued follow-up was 57 months. Conclusion: Chemoembolization therapy is effective in reducing tumor size, bilirubin, AFP and prolonging survival time for patients under 40 years old with HCC. Keywords: chemoembolization therapy, hepatocellular carcinoma

SUMMARY Sentinel lymph node is defined as the first lymph node or group of first nodes to which cancer cells are likely to spread from the primary tumor. Cancer cells are often found in sentinel lymph node(s) before metastasizing to other nodes or organs. Therefore, sentinel lymph node biopsy plays an important role in identification and management of metastasis lesions, especially in breast cancer, testicular cancer and melanoma. Sentinel lymph node scintigraphy with SPECT/CT using 99mTechnetiumnanocolloid is a useful imaging technique for nodal determination and localization. With negative histopathological results of sentinel lymph node dissection, axillary lymph node dissection can be avoided for patients thereby reducing the risk of lymphedema and other complications. In this article, two patients in Vinmec Health Care System, Times City with breast cancer who underwent SPECT/CT sentinel lymph node scintigraphy were reported. Keywords: breast cancer, sentinel lymph node, SPECT/CT, 99mTc-nanocolloid

SUMMARY Purpose: This report aimed to assess the describing imaging characteristic of gastric cancer on 256 - Slice Multidetector Computed Tomography gastrography. Materials and methods: 256 - slice multidetector CT gastrography in 31 patients with histopathological findings of gastric cancer from 2020 Fer to 2021 August at Huu Nghi hospital. Results: Gastric cancer is often detected in old people. The most common position is the antrum of gastric (71%), the least common position is the cardia - fundus of gastric (3,2%).There is a correlation between diameter of tumors and T staging (p< 0,05). There are correlation between the shape, short diameters of nodes and LN metastasis (p< 0,05). Short diameters of nodes is ≥ 8 mm and round shape of nodes were moderate diagnostic ability indicator for LN metastasis in gastric cancer. Conclusion: 256 slice - MDCT gastrography is an effective method and non-invasion offers improved detected gastric cancer and evaluates lymph node metastasis. Keyword: Gastric cancer,256 slice - MDCT,short diameters of Lymph node metastasis.

SUMMARY Purpose: To apply the CAD-RADS classification in the assessment of chronic coronary artery disease on multislice computed tomography. Material and methods: Cross-sectional description of 179 patients undergoing coronary computed tomography angiography, diagnosed according to CAD-RADS classification by two physicians independently, the intra-class correlation was used to test the inter-reviewer agreement (IRA), and comparing with results invasive coronary angiography. Results: There was an excellent IRA between the two for CADRADS (κ=0.904), by each CAD-RADS classification (κ=0.827-1.00), by coronary artery stenosis (κ=0.878-0.931). There is an excellent IRA for modifiers G (κ=1), and S (κ=1), moderate IRA for V (κ=0.574). The best cutoff value for predicting significant CAD was ≥ CAD-RADS 3. The diagnostic value of CAD-RADS classification according to the common segment: sensitivity 77.54%, specificity 87.23%, positive predictive value 89.92%, negative predictive value 72.56%. Conclusion: There is an excellent inter-reviewer agreement when applying the CAD-RADS classification to clinical practice, with high sensitivity, specificity, and accuracy when compared with invasive coronary angiography. Keywords: coronary artery, CAD-RADS, CT angiography, graft, stent

SUMMARY Background: In laparoscopic donor nephrectomies, it is important to understand the exact anatomy of the vascular structures during minimally invasive surgery. The aim of study: to determine the accuracy of MDCT to predict vascular anatomy in living kidney donors and to reveal the prevalence of vascular variations in a VietNam population. Materials and methods: This is a retrospective cross-sectional study. One hundred and eleven living donors were included in this study, who had MDCT for the assessment of their renal vessels and laparoscopic surgery in Cho Ray hospital between February 2020 to April 2021. The initial CT results were compared with the surgical findings and repeated review sessions of CT scans were performed to determine the causes of mismatches in discordant cases. Results: The accuracy of MDCT was 98,2% to predict the number of renal vessels. One artery was missed during the initial CT interpretation due to perception error. One case is false positive. The accuracy of MDCT was 95,5% to predict the early branching of a renal artery and late confluence of a renal vein variation. The prevalence of multiple renal arteries and veins, early branching of a renal artery and late confluence of a renal vein were 20,7%, 6,8%, 13,5%, 19,8%. One case (0,9%) each of a retroaortic left renal vein and a circumaortic left renal vein were found. Conclusion: Multidetector computed tomography is a reliable technique in preoperative renal anatomy evaluation in live renal donors. Key word: living donor kidney, multidetector computed tomography (MDCT) *