Role of contrast-enhanced ultrasound in follow-up assessment after ablation for hepatocellular carcinoma

AIM:To assess the usefulness of contrast-enhanced ultrasound (CEUS) during follow-up after percutaneous ablation therapy for hepatocellular carcinoma (HCC).METHODS:A total of 141 patients with HCCs who received percutaneous ablation therapy were assessed by paired follow-up CEUS and contrast-enhanced computed tomography (CECT).The follow-up scheme was designed prospectively and the intervals between CEUS and CECT examinations were less than 14 d.Both im-ages of follow-up CEUS and CECT were reviewed by radiologists.The ablated lesions were evaluated and classified as local tumor progression (LTP) and LTPfree.LTP was defined as regrowth of tumor inside or adjacent to the successfully treated nodule.The detected new intrahepatic recurrences were also evaluated and defined as presence of intrahepatic new foci.On CEUS and CECT,LTP and new intrahepatic recurrence both were displayed as typical enhancement pattern of HCC (i.e.,hyper-enhancing during the arterial phase and washout in the late phase).With CECT as the reference standard,the ability of CEUS in detecting LTP or new intrahepatic recurrence during follow-up was evaluated.RESULTS:During a follow-up period of 1-31 mo (median,4 mo),169 paired CEUS and CECT examinations were carried out for the 141 patients.For a total of 221 ablated lesions,266 comparisons between CEUS and CECT findings were performed.Thirty-three LTPs were detected on CEUS whereas 40 LTPs were detected on CECT,there was significant difference (P < 0.001).In comparison with CECT,the numbers of false positive and false negative LTPs detected on CEUS were 6 and 13,respectively;the sensitivity,specificity,positive predictive value (PPV),negative predictive value (NPV) and overall accuracy of CEUS in detecting LTPs were 67.5%,97.4%,81.8%,94.4% and 92.3%,respectively.Meanwhile,131 new intrahepatic recurrent foci were detected on CEUS whereas 183 were detected on CECT,there was also significant difference (P < 0.05).In comparison with CECT,the numbers of false positive and false negative intrahepatic recurrences detected on CEUS were 13 and 65,respectively;the sensitivity,specificity,PPV,NPV and overall accuracy of CEUS in detecting new intrahepatic recurrent foci were 77.7%,92.0%,92.4%,76.7% and 84.0%,respectively.CONCLUSION:The sensitivity of CEUS in detecting LTP and new intrahepatic recurrence after percutaneous ablation therapy is relatively low in comparisonwith CECT.

Feasibility of Transabdominal Real-time CDFI and HDFI Techniques for Fetal Pulmonary Vein Display in the First Trimester

Objective This study aimed to assess the feasibility and usefulness of transabdominal color Doppler flow imaging(CDFI)technology and the high-definition flow imaging(HDFI)technique in detecting fetal pulmonary veins(PVs)in the first trimester(11–13^(+6)weeks).Methods From December 2018 to October 2019,328 pregnant women with 328 normal singleton fetuses(crown-rump length:45–84 mm)who had undergone CDFI and HDFI scans for fetal heart and vessel examination were enrolled in this study.The cases were divided into three groups according to the gestational age:group A,11^(+0)−11^(+6)weeks;group B,12^(+0)−12^(+6)weeks;and group C,13^(+0)−13^(+6)weeks.Baseline sonograms and CDFI and HDFI images were analyzed by two senior radiologists independently and blindly.The abilities of CDFI and HDFI to display PVs were compared.Results Successful PV display rates via CDFI and HDFI were 2.3%and 68.2%(P<0.01),22.4%and 82.4%(P<0.01),41.5%and 91.2%(P<0.01)for group A,group B,and group C,respectively.The total successful display rates for the two methods were 28.9%(CDFI)and 84.8%(HDFI)(P<0.01).Conclusions The HDFI technique is more valuable than CDFI for detecting PVs in early pregnancy(11–13^(+6)weeks).HDFI can detect at least one PV in all cases and may be used to detect pulmonary venous anomalies early.

Misdiagnosis of pancreatic metastasis from renal cell carcinoma:A case report

BACKGROUND Pancreatic metastases account for only a small proportion of all pancreatic malignancies.Isolated pancreatic metastasis from renal cell cancer(isPM-RCC)is extremely rare and may be difficult to differentiate from more common primary neoplasms.A history of nephrectomy is crucial for the diagnosis.CASE SUMMARY We report the case of a 64-year-old Asian man who was diagnosed with a mass in the pancreatic head using computed tomography.He had no related symptoms,and his medical history was unremarkable,except for unilateral nephrectomy performed to remove a“benign”tumor 19 years ago.All preoperative imaging findings suggested a diagnosis of pancreatic neuroendocrine tumor.However,ultrasound-guided biopsy revealed features of clear cell renal cell carcinoma(ccRCC).Re-examination of the specimen resected 19 years ago confirmed that he had a ccRCC.The pancreatic mass was resected and pathological examination confirmed isPM-RCC.CONCLUSION Misdiagnosis of isPM-RCC is common because of its rarity and the long interval from resection of the primary tumor and manifestation of the metastasis.The history of the previous surgery may be the only clue.