Thyroid gland tumor diagnosis at US elastography

PURPOSE: To prospectively evaluate the elastographic appearance of thyroid gland tumors and explore the potential sensitivity and specificity of ultrasonographic (US) elastography for differentiating benign and malignant tumors, with histopathologic analysis as the reference standard. MATERIALS AND METHODS: The study was institutional review board approved, and each patient gave written informed consent. Fifty-two thyroid gland lesions (22 malignant, 30 benign) in 31 consecutive patients (six men, 25 women; mean age, 49.7 years +/- 14.7 [standard deviation]) were examined with real-time elastography in the elasticity imaging mode implemented on a clinical US scanner modified for research. In addition, the radiofrequency echo data stored during US were exported from the scanner and used for off-line strain image reconstruction. All elastograms were evaluated for the lesion visibility, relative brightness, and margin regularity and definition by using a four-point scale. In addition, normal thyroid gland tissue and thyroid gland tumor strains were measured on off-line processed elastograms, and the thyroid gland-to-tumor strain ratio (ie, strain index) was calculated. The potential of elastographic criteria for the diagnosis of thyroid gland cancer was evaluated with univariate analysis and multivariate logistic regression. Qualitative variables were compared by using the chi2 test, and quantitative variables were compared by using the Mann-Whitney U test. P < .05 was considered to indicate significance. RESULTS: A strain index value greater than 4 on off-line processed elastograms was the strongest independent predictor of thyroid gland malignancy (P < .001); this criterion had 96% specificity and 82% sensitivity. Two other elastographic criteria, which were evaluated on real-time elastograms--a margin regularity score higher than 3 (88% specificity, 36% sensitivity) and a tumor area ratio higher than 1 (92% specificity, 46% sensitivity)--also were associated with malignancy (P < .05). However, the usefulness of these criteria was not considered to be high because of their low sensitivity. CONCLUSION: Elastography is a promising imaging technique that can assist in the differential diagnosis of thyroid cancer.     

New ultrasound technologies for the diagnostics of prostate cancer

CLINICAL/METHODOLOGICAL ISSUE: Prostate cancer is the most common cancer in men. The diagnosis is based on prostate-specific antigen (PSA), digital rectal examination (DRE) and transrectal ultrasound (TRUS) guided biopsy. These techniques have considerable limitations, which result in unnecessary biopsies. Furthermore the biopsies are associated with morbidity and costs. STANDARD RADIOLOGICAL METHODS: Standard gray-scale ultrasound has a low sensitivity and specificity for prostate cancer detection. METHODOLOGICAL INNOVATIONS: New ultrasound technologies, including color- and power Doppler ultrasound, contrast enhanced US and real-time sonoelastography have shown to improve prostate cancer diagnosis. PERFORMANCE: Contrast-enhanced ultrasound has shown a sensitivity of 100% (95% CI, 95%), a negative predictive value (NPV) of 99.8% and a positive predictive value (PPV) of 88.8% for prostate cancer detection. Real-time sonoelastography has shown a sensitivity of 86%, a specificity of 81% and NPV of 91% for prostate cancer diagnosis. ACHIEVEMENTS: Most studies show that these new ultrasound modalities demonstrate a 1.5 to 2.5 times higher detection of prostate cancer per biopsy specimen compared with systematic biopsy. Multicenter studies results are at present lacking but are, however ongoing. PRACTICAL RECOMMENDATIONS: In patients with suspected prostate cancer (elevated PSA, suspicious DRE) these new ultrasound techniques should be used. These techniques can detect prostate cancer and allow a targeted biopsy approach.     

Diagnosis of thyroid cancer in children: value of gray-scale and power doppler US

PURPOSE: To prospectively analyze the accuracy of various diagnostic criteria for cancer in solid thyroid nodules in children on the basis of gray-scale and power Doppler ultrasonographic (US) findings. MATERIALS AND METHODS: The study protocol was approved by the institutional review board, and patient's parents gave full informed consent. One hundred three consecutive pediatric patients with solid thyroid nodules were included in the study. Thirty-five patients had thyroid cancer (mean age, 14.6 years +/- 2.6 [standard deviation]; range, 10-18 years), and 68 patients had benign thyroid nodules (mean age, 14.2 years +/- 2.9; range 9-18 years). Three-dimensional US was used to determine the volume of thyroid gland and thyroid nodules. Results of nodule cytologic and histologic examination and long-term clinical and US follow-up were used as a proof of final diagnosis. The following US characteristics were evaluated: location, echogenicity, echotexture, outline, presence of a halo, microcalcifications, and type of vascularization. Multivariate logistic regression analysis was used to evaluate the accuracy of US criteria for thyroid cancer in lesions with diameter of 15 mm and smaller and lesions with diameter larger than 15 mm. Qualitative variables were compared by using the chi(2) test and quantitative variables were compared by using the Student t test. Significance was defined at P < .05. RESULTS: In thyroid nodules with diameter of 15 mm and smaller, the most reliable diagnostic criteria for malignancy were an irregular outline (sensitivity, 69.6%; specificity, 86.4%; P < .001), subcapsular location (sensitivity, 65.2%; specificity, 86.4%; P < .001), and increased intranodular vascularization (sensitivity, 69.6%; specificity, 87.9%; P < .01). For thyroid nodules larger than 15 mm in diameter, the accuracy of US diagnosis was much lower than that for smaller nodules. The only reliable criterion for cancer in this group was hypoechogenicity (sensitivity, 60.0%; specificity, 84.0%; P < .01). CONCLUSION: Study findings indicate that US is most helpful in diagnosis of thyroid malignancy in thyroid nodules with diameter of 15 mm and smaller, with detection of irregular tumor outline, subcapsular location, and increased intranodular vascularization.     

Prostate cancer: three-dimensional sonoelastography for in vitro detection

PURPOSE: To prospectively evaluate the accuracy of three-dimensional (3D) sonoelastographic imaging, relative to that of gray-scale ultrasonography (US), in the in vitro detection of prostate cancer. MATERIALS AND METHODS: The study was approved by the institutional review board and was HIPAA compliant. Informed consent was obtained from all patients. Nineteen prostatectomy specimens from patients aged 46-70 years with biopsy-proved prostate cancer were scanned in three dimensions by using conventional B-mode US and sonoelastography with vibrations of more than 100 Hz. Step-sectioned whole-mount histologic specimens were used to create a 3D volume of the prostate and the tumors within it. B-mode US scans and regions of low vibration on the sonoelastographic images (hard regions) were formatted in three dimensions. The lesions in the 19 cases were classified into two groups, as follows: G1 lesions were pathologically confirmed tumors with a volume of at least 1.0 cm3, and G2 lesions were pathologically confirmed tumors smaller than 1.0 cm3. G1 lesions were evaluated with B-mode US and sonoelastography and classified as true-positive, false-positive, true-negative, or false-negative; G2 lesions were evaluated only with sonoelastography. Findings at histologic examination were used as the reference standard. True-positive findings necessitated 3D lesion correlation between pathologic and imaging data. Conventional definitions of accuracy and sensitivity were used for statistical analysis. RESULTS: For G1 lesions (seven lesions with a volume of at least 1.0 cm3), sonoelastography had an accuracy of 55% and a sensitivity of 71% and B-mode US had an accuracy of 17% and a sensitivity of 29%. The mean tumor volume was 3.1 cm3 +/- 2.1 (standard deviation). For G2 lesions (22 lesions with a volume of less than 1.0 cm3), the mean tumor volume was 0.32 cm3 +/- 0.21. Sonoelastography had an accuracy of 34% and a sensitivity of 41%; there were six false-positive findings. CONCLUSION: Sonoelastography performed considerably better than did gray-scale US in the depiction of prostate cancer for tumors with volumes of more than 1 cm3.     

Breast lesions: imaging with contrast-enhanced subharmonic US--initial experience

PURPOSE: To prospectively compare accuracy of gray-scale subharmonic imaging (SHI) with that of standard gray-scale ultrasonography (US), power Doppler US (with and without contrast material), and mammography for the diagnosis of breast cancer, with histopathologic or clinical follow-up results as the reference standard. MATERIALS AND METHODS: This HIPAA-compliant pilot study had institutional review board approval; all subjects gave written informed consent. Fourteen women (age range, 37-66 years) had 16 biopsy-proved breast lesions. In SHI, pulses are transmitted at one frequency, but only echoes at half that frequency (the subharmonic) are received. A US scanner was modified to perform gray-scale SHI (transmitting at 4.4 and receiving at 2.2 MHz). Precontrast imaging (gray-scale US and power Doppler) was followed by contrast material-enhanced power Doppler and gray-scale SHI. A reader blinded to mammographic and pathologic findings assessed diagnosis on a six-point scale. Sensitivity, specificity, accuracy, and receiver operating characteristic (ROC) curves were computed for mammography, gray-scale and power Doppler imaging (pre- and postcontrast), and SHI. RESULTS: Of the 16 lesions, four (25%) were malignant. Mammography had 100% sensitivity and 20% specificity. Sensitivity and specificity, respectively, were 50% and 92% for precontrast imaging and 75% and 75% for contrast-enhanced power Doppler. SHI had 75% sensitivity and 83% specificity. Specificity was higher for all US modes than for mammography (P<.04). There were no significant differences in specificity among US modes or in sensitivity (P>or=.50). Area under the ROC curve for the diagnosis of breast cancer was 0.64 for standard gray-scale US and power Doppler US, 0.67 for contrast-enhanced power Doppler US, 0.76 for mammography, and 0.78 for SHI (P>.20). Contrast enhancement was better with SHI than with power Doppler (100% vs 44% of lesions with good or excellent enhancement; P=.004). CONCLUSION: SHI appears to improve the diagnosis of breast cancer relative to conventional US and mammography, albeit on the basis of results in a very limited number of subjects.     

Ultrasound diagnosis of lymph node metastasis in head and neck cancer

The role of ultrasonic (US) examination in the detection of cervical lymph node metastasis from head and neck cancer has been evaluated. The subjects were 57 patients with carcinoma of the oral cavity, maxillary sinus or oropharynx who underwent radical neck dissection. The preoperative US and postoperative histopathological findings were compared in 181 lymph nodes (LNs) of 5 mm or more in diameter. LNs were evaluated by US with reference to their size, shape, boundary and internal echoes. The histologically positive rate was higher for larger LNs on US scans: 96% (44/46) of LNs of 15 mm or more were positive. On the other hand, 95% (18/19) of the flat LNs were negative. The positive rate was higher for well delineated than poorly delineated LNs, but similar among the homogeneous, heterogeneous and reflective core patterns of internal echoes. No LNs were detected by US in six of the 57 patients, of which four were true negative and the other two false negative. In the two false negative patients, histopathological examination showed a total of four LNs with two showing extensive extranodal spread of tumour and fibrosis of the surrounding tissue due to previous radiotherapy. Whether LNs are metastatic or not is difficult to determine directly by US. However, the positive rate can be enhanced by evaluation of the size, shape and boundary of the LN. US is indispensable for diagnosing cervical lymph node metastasis in patients with malignant head and neck tumours.     

Can ultrasound elastography distinguish metastatic from reactive lymph nodes in patients with primary head and neck cancers?

Objectives

The purpose of this study was to evaluate the diagnostic utility of real-time elastography (RTE) in differentiating between reactive and metastatic cervical lymph nodes (LN) in patients with primary head and neck cancer in comparison with the conventional B mode and power Doppler parameters.

Methods

A total of 127 lymph nodes in 78 patients with primary head and neck cancer were examined by B-mode sonography, power Doppler ultrasound and elastography. Elastographic patterns were determined on the distribution and percentage of the lymph node area with low elasticity (hard), with pattern 1 being an absent or very small hard area to pattern 5, a hard area occupying the entire lymph node. Patterns 3–5 were considered metastatic. Ultrasound guided aspiration cytology was done for 57 lymph nodes. Excision biopsy was done for 52 lymph nodes. Eighteen lymph nodes responded to conservative treatment, and were considered reactive.

Results

The majority (85.3%) of the metastatic lymph nodes had elastography pattern 3–5. This finding was observed in only 5% of the benign lymph nodes (P < 0.001). The elastography pattern had sensitivity of 85.3%, specificity of 95.5%, PPV of 97.2%, NPV of 78.1% and overall accuracy of 88.9% in differentiation between benign and malignant lymph nodes. On the other hand, for the B mode criteria, the best accuracy was given to abnormal hilum (83%). The accuracy of power Doppler ultrasound pattern was 70.8%.

Conclusions

The accuracy of sonoelastography is higher than usual B mode and power Doppler ultrasound parameters in differentiation between benign and malignant nodes. The integration of lymph node sonoelastography in the follow up of patients with known head and neck cancer may reduce the number of biopsies.     

FDG-PET in the Locoregional Lymph Node Staging of Non-small Cell Lung Cancer. A Comprehensive Review of the Leuven Lung Cancer Group Experience

Exact staging of locoregional lymph node (LN) disease in non-small cell lung cancer (NSCLC) is of considerable clinical interest. Computed tomography (CT) is not very accurate for this purpose. In the past years, we performed several prospective studies examining the role of [18F]fluoro-2-deoxy-D-glucose-positron emission tomography (FDG-PET) in this setting. We compared the accuracy of CT, PET, and PET read with the anatomical aid of CT images in the distinction of early-stage operable cases (i.e., without metastatic LN or with only hilar metastatic LN) versus locally advanced cases (with metastatic mediastinal LN). LNs on PET were recorded as metastatic if the FDG-uptake was more intense than the mediastinal blood pool activity. In 105 patients (or an analysis of 980 LN stations), the accuracy of PET (85%) was significantly better than that of CT (64%; P = 0.0003). Visual correlation with CT images further improved the results to an accuracy of 90%. We also examined the value of different acquisition protocols and interpretation algorithms. The use of Standardized Uptake Values (SUVs) of LNs, or of anatometabolic PET-CT-fusion images, did not prove to be of additional value compared to visual PET-reading and correlation with the CT images. On the condition that positive-LN findings on PET are always confirmed by mediastinoscopy, a simple whole-body acquisition protocol is adequate. We conclude that FDG-PET plays an important role in LN-staging in NSCLC. The very high negative predictive value of mediastinal FDG-PET is able to reduce the need for invasive surgical staging substantially.     

Detection of axillary lymph node metastasis with diffusion-weighted MR imaging

The feasibility of detecting axillary lymph node (LN) metastases with diffusion-weighted MR imaging was retrospectively evaluated. The relative ADC (with b values of 0 and 1000 s/mm²) between LNs in each axillary space was calculated (n=75). The area, the long and short diameter of the metastatic LNs were compared to those of non-metastatic LNs. The relative ADC value of metastatic LNs was significantly lower than that of non-metastatic LNs (P=.00). The long and short diameter LN diagnostic performance was superior to that of mean ADC and relative ADC (AUC: 0.84, 0.80 versus 0.64, 0.03), suggesting usefulness of diameter over ADC.     

Diagnostic role of F-18 FDG PET/CT for preoperative lymph node staging in thyroid cancer patients; A systematic review and metaanalysis

PurposeAlthough ultrasonography (US) is a standard technique for the assessment of cervical lymph node (LN) metastasis, the role of F-18 fluorodeoxyglucose (FDG) positron emission tomography-computed tomography (PET-CT) is increasingly reported. The purpose of this study is to assess the diagnostic accuracy of F-18 FDG PET-CT for detection of cervical LN metastasis in thyroid cancer (TCa) patients through a meta-analysis.Patients and methodsThe PubMed, Cochrane Database, and Embase from the earliest available date of indexing through September 31, 2019, were searched for studies evaluating the diagnostic performance of F-18 FDG PET-CT for detection of LN metastasis in TCa. We determined the sensitivities and specificities across studies, calculated positive and negative likelihood ratios (LR+ and LR-), and constructed summary receiver operating characteristic curves.ResultsAcross 9 studies (759 patients), the pooled sensitivity for F-18 FDG PET-CT for all cervical LN metastasis in TCa was 0.30 (95% CI; 0.26–0.35) a pooled specificity of 0.94. For central LN metastasis, the pooled sensitivity was 0.28 (95% CI; 0.21–0.34) and a pooled specificity was 0.87 (95% CI; 0.83–0.90). For lateral LN metastasis, the pooled sensitivity was 0.56 (95% CI; 0.50–0.62) and a pooled specificity was 0.94.ConclusionsF-18 FDG PET-CT shows a low sensitivity and high specificity for the detection of metastatic LNs in patients with TCa. The current data suggests that F-18 FDG PET-CT is not indicated in the work up of patients with thyroid cancer or biochemical evidence of recurrent disease.     

Diagnosis supporting algorithm for lymph node metastases from colorectal carcinoma on 18F-FDG PET/CT

Objective We studied the improvement of the detect-ability of lymph node (LN) metastases from colorectal cancer in ¹⁸F-fluorodeoxyglucose positron emission tomography (FDG PET)/computed tomography (CT) by analyzing the acquired counts with a statistical method. Methods Thirty-nine metastatic LNs from 32 cases with colorectal cancer were included in this study. “Uptake region” was defined as the site where counts were higher than the average plus 3 standard deviations (SDs) on each transaxial image of FDG PET. After the initial uptake regions were selected, these high accumulation areas were automatically excluded from consideration thereafter. This method was repeated and new uptake regions were identified. This method was repeated up to five times. After that, the stacked-up uptake regions were compared with computed tomography (CT) images, and the high accumulation areas that were superimposed on the normal structures, such as intestine, vessels, and ureters, were excluded from the consideration. The remaining uptake regions were diagnosed as metastatic LNs, and the detectability of LN metastases was calculated. We then compared these statistical results with the results obtained on the basis of visual assessments by radiologists. Results Our proposed method showed the best results when the procedures were repeated three times in the light of detectability. After being repeated three times, this method detected 15/23 (65.2%) metastatic LNs in the first LN group, 16/16 (100%) in the second-third LN groups and 31/39 (79.4%) in the total LNs, whereas the radiologists diagnosed 8/23 (34.8%) of metastatic first LNs, 12/16 (75.0%) in the second-third LNs and 20/39 (51.3%) in the total LNs. A statistically significant difference was observed between the result of iteration number 3 and that by radiologists as for the second—third LNs and the total LNs. Conclusions This study suggests that our proposed statistical method could improve the detectability of LN metastases from colorectal cancer. Our method will help radiologists to detect small metastatic lesions such as LN metastases.     

Doppler power with contrast media in the characterization of renal masses

PURPOSE: To report the results of a prospective study investigating the potentials of contrast-enhanced power Doppler in the diagnosis of expansive renal lesions. MATERIAL AND METHODS: From 1997 to October 30, 1999, we studied 59 expansive renal lesions (28 malignant, 31 benign) in 48 patients (mean age 55 years, range 10-79) with power Doppler US before and after the administration of an echo-enhancing agent (Levovist, Schering AG, Berlin, Germany). We identified 5 patterns of vascular architecture of the lesions, both before and after contrast agent administration, following the classification by Jinzaki e Coll. RESULTS AND DISCUSSION: Power Doppler US showed vascular structures in 34 patients. The administration of Levovist revealed vessels in 12/25 lesions which had none at baseline studies and in 6 cases vascularity was particularly evident. Color signals were enhanced in all the 34 vascularized lesions, which allowed better definition of vascular patterns. The characterization of vascular patterns with baseline power Doppler US helped improve diagnostic accuracy compared to gray-scale US (58% versus 32%) for hyperechoic lesions, complex cysts and pseudomasses. Independent of contrast agent administration, the integration of gray-scale and power Doppler modes increased diagnostic accuracy even further (76% correct diagnoses). CONCLUSIONS: In our series, the US contrast agent did not increase the diagnostic accuracy of power Doppler in the differential diagnosis of hyperechoic renal lesions; conversely, Levovist can be advantageous for the characterization of suspected pseudomasses and complex cysts.     

Indeterminate ovarian mass at US: incremental value of second imaging test for characterization--meta-analysis and Bayesian analysis

PURPOSE: To compare value of current diagnostic strategies in assessment of changes in posttest probability of ovarian cancer when menopausal status and combination and sequence of diagnostic imaging tests are considered. MATERIALS AND METHODS: Prevalence of ovarian cancer according to menopausal status in women with an ovarian mass and performance of combined gray-scale and Doppler ultrasonography (US), computed tomography (CT), and non-enhanced magnetic resonance (MR) imaging and contrast material-enhanced MR imaging after indeterminate results at gray-scale US were derived from meta-analysis by using MEDLINE database and institutional data. Study was approved by the institutional review board of University Hospital Geneva, Geneva, Switzerland; informed consent was waived. Posttest probability values were computed through Bayesian analysis and Monte Carlo simulation after initial gray-scale US and secondary combined gray-scale and Doppler US, CT, or MR imaging, while dependence of test results among imaging modalities was considered. Changes in posttest probability were compared among imaging modalities with summary receiver operating characteristic curves. RESULTS: Prevalence of ovarian cancer was 8.75% in premenopausal women and 32.40% in postmenopausal women with an ovarian mass. After characterization with initial gray-scale US, posttest probability in pre- and postmenopausal women changed, respectively, to 25% and 63% for indeterminate results and to 2% and 7% for benign results. Subsequent use of combined gray-scale and Doppler US, CT, or MR imaging had significant higher positive and lower negative posttest probability than did use of gray-scale US alone. In women with an indeterminate initial US result, posttest probability decreased after secondary testing with benign results for all imaging modalities to 2% in premenopausal women and to 8%-10% in postmenopausal women. After secondary testing for suspicious lesions, posttest probability increased more after non-enhanced (premenopausal women, 70%; postmenopausal women, 92%) or contrast-enhanced MR imaging (premenopausal women, 80%; postmenopausal women, 95%) than it did after combined gray-scale and Doppler US (premenopausal women, 30%; postmenopausal women, 69%) or CT (premenopausal women, 38%; postmenopausal women, 76%) (P < .001). CONCLUSION: In women with an indeterminate ovarian mass at gray-scale US, MR imaging results contributed to change in probability of ovarian cancer in both pre- and postmenopausal women more than did CT or combined gray-scale and Doppler US results.     

Role of ultrasound in the preoperative staging of patients with breast cancer

The aim of this study was to evaluate the ability of axillary ultrasound (US) and US-guided fine-needle aspiration biopsy (FNAB) to detect axillary LN metastases. Between January 2001 and September 2003, axillary US was performed in 165 patients with cytologically or histologically proven breast cancer and clinically non-palpable axillary LNs. In patients with US suspicious LNs, US-guided FNAB was performed and patients with cytologically proven malignant LNs proceeded directly to the ALND. In 49/90 patients with US suspicious LNs, US-guided FNAB was performed. It was positive in 33/49 patients. Definitive histology report revealed LN metastases in 65/165 patients. The sensitivity, specificity, positive and negative predictive value of the US-FNAB, were 84, 91, 97 and 62%. Axillary US in a combination with US-FNAB is a valuable method in preoperative staging of patients with breast cancer. Almost 50% of patients with LN metastases can be spared the second operation. However, it is very much operator-dependent and equipment-dependent.     

Heterogeneity Analysis of 18F-FDG Uptake in Differentiating Between Metastatic and Inflammatory Lymph Nodes in Adenocarcinoma of the Lung: Comparison with Other Parameters and its Application in a Clinical Setting

Purpose

Lymph node (LN) characterization is crucial in determining the stage and treatment decisions in patient with lung cancer. Although ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) has a higher diagnostic accuracy in LN characterization than anatomical imaging, differentiating between metastatic and inflammatory LNs is still challenging because both could show high ¹⁸F-FDG uptake. The purpose of this study was to assess if the heterogeneity of the ¹⁸F-FDG uptake could help in differentiating between inflammatory and metastatic LNs in lung cancer, and to compare with other parameters.

Methods

A total of 44 patients with adenocarcinoma of the lung, who underwent preoperative ¹⁸F-FDG PET/CT without having any previous treatments and were revealed to have ¹⁸F-FDG-avid LNs, were enrolled. There were 52 pathology-proven metastatic lymph nodes in 26 subjects. The pathology-proven metastatic LNs were compared with 42 pathology-proven inflammatory/benign LNs in 18 subjects. The coefficient of variation (CV) was used to assess the heterogeneity of ¹⁸F-FDG uptake by dividing the standard deviation of standardized uptake value (SUV) by mean SUV. The volume of interest was manually drawn based on the combined CT images of ¹⁸F-FDG PET/CT (no threshold is used). Comparisons were made with the maximum standardized uptake values (SUVmax), visual assessment of ¹⁸F-FDG uptake, longest diameter, and maximum Hounsfield units (HUmax).

Results

Metastatic lymph nodes tended to have higher CVs than the inflammatory LNs. The mean CV of metastatic LNs (0.30 ± 0.08; range: 0.08–0.55) was higher than that of inflammatory LNs (0.17 + 0.06; range, 0.07–0.32; P < 0.0001). On receiver operating characteristic (ROC) curve analysis, the area under curve was 0.901, and using 0.20 as cut-off value, sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy were 88.5 %, 76.2 %, 82.2 %, 84.3, and 83.0 % respectively. Accuracy of CV was slightly higher than SUVmax and diameter, but significantly higher than visual assessment and HUmax.

Conclusions

In patients with adenocarcinoma of the lung having no prior treatments, metastatic LNs showed more heterogeneous ¹⁸F-FDG uptake than inflammatory LNs. Measuring the CV of the SUV derived from a manual volume of interest (VOI) can be helpful in determining metastatic LN of adenocarcinoma of the lung. Including diagnostic criteria of CV into the diagnostic approach can increase the accuracy of mediastinal node status.     

Comparison of DWI and PET/CT in evaluation of lymph node metastasis in uterine cancer

AIM: To investigate diffusion-weighted imaging (DWI) and positron emission tomography and computed tomography (PET/CT) with Ⅳ contrast for the preoperative evaluation of pelvic lymph node (LN) metastasis in uterine cancer. METHODS: Twenty-five patients with endometrial or cervical cancer who underwent both DWI and PET/CT before pelvic lymphadenectomy were included in this study. For area specific analysis, LNs were divided into eight regions: both common iliac, external iliac, internal iliac areas, and obturator areas. The classification for malignancy on DWI was a focally abnormal signal intensity in a location that corresponded to the LN chains on the T1WI and T2WI. The criterion for malignancy on PET/CT images was increased tracer uptake by the LN.RESULTS: A total of 36 pathologically positive LN areas were found in 9 patients. With DWI, the sensitivity, specificity, positive predictive value, negative predictive value and accuracy for detecting metastatic LNs on an LN area-by-area analysis were 83.3%, 51.2%, 27.3%, 93.3% and 57.0%, respectively, while the corresponding values for PET/CT were 38.9%, 96.3%, 70.0%, 87.8% and 86.0%. Differences in sensitivity, specificity and accuracy were significant (P < 0.0005). CONCLUSION: DWI showed higher sensitivity and lower specificity than PET/CT. Neither DWI nor PET/CT were sufficiently accurate to replace lymphadenectomy.     

多层螺旋CT对结肠癌术前淋巴结转移 诊断价值的研究

目的 探讨多层螺旋CT（MSCT）诊断结肠癌术前腹腔淋巴结转移的价值。方法 回顾性分析2015年3月-2017年1月间在我院经手术病理确诊为结肠癌的58例病人的临床及影像资料，其中男32例，女26例；年龄31~78岁，平均（49.58±14.28）岁。对术前MSCT检测到的腹腔可疑转移淋巴结进行分析，分别以淋巴结短径、相对强化值及综合上述2种参数等作为判定淋巴结转移的标准，并采用Kappa检验对MSCT诊断及术后病理结果的一致性进行分析。结果 与病理结果对照分析后发现，以淋巴结短径≥8 mm、相对强化值≥50 HU及短径≥5 mm且相对强化值≥30 HU作为判断淋巴结转移的标准时MSCT诊断与病理结果一致性相对较好（κ分别为0.809、0.764、0.786）。在不同的腹腔淋巴结分布区域，上述3种诊断标准用于肠旁淋巴结组时，诊断结果与病理结果的一致性较好（κ分别为0.816、0.802、0.800），用在肠系膜中及肠系膜根部淋巴结组时，诊断结果与病理结果的一致性中等（κ分别为0.631、0.673、0.574及0.527、0.626、0.502）。结论 MSCT可根据淋巴结大小、强化差值等参数对结肠癌病人术前淋巴结转移做出判断，从而为评估临床预后提供重要信息。     

Predictors of prostate carcinoma: accuracy of gray-scale and color Doppler US and serum markers

PURPOSE: To determine the accuracy of detecting prostate cancer by using (a) gray-scale and color Doppler transrectal ultrasonography (US), (b) serum and excess prostate-specific antigen (PSA) levels, and (c) targeted and sextant transrectal US-guided biopsy. The relationship between US-detected neovascularity and tumor biologic activity was also evaluated. MATERIALS AND METHODS: Between 1995 and 1999, 544 patients with elevated PSA levels and/or abnormal digital rectal examination underwent transrectal US-guided sextant biopsy and targeted biopsy of US abnormalities. Sensitivity, specificity, and accuracy of gray-scale US, color Doppler US, targeted biopsy, and PSA and excess PSA were calculated. RESULTS: Gray-scale US depicted 78 (41.1%) of 190 cancers, whereas color Doppler US depicted 30 (15.8%) additional cancers. Targeted biopsy was used to detect 108 (56.8%) cancers, whereas sextant biopsy was used to detect 82 (43.2%) additional cancers. Although US-visible cancers had a higher Gleason grade than did cancers discovered at sextant biopsy (P <.05), 25 of the 66 cancers identified with sextant biopsy alone were Gleason grade 6 or higher. Color Doppler US-depicted hypervascularity correlated with biologically aggressive tumors. Excess PSA was normal in 58 (30.5%) cancers, with an accuracy of 67.3%, resulting in better prediction of prostate tumors than with serum PSA level alone. CONCLUSION: Gray-scale transrectal US, even coupled with color Doppler US, is inadequate for prostate carcinoma screening; therefore, targeted biopsy should always be accompanied by complete sextant biopsy sampling.     

Differential diagnosis of small round cervical lymph nodes: comparison of power Doppler US with contrast-enhanced CT and pathologic results

PURPOSE: The purpose of this study was to differentiate reactive small round lymph nodes (SRLNs) from metastases by power Doppler ultrasonography (PD-US) and contrast-enhanced CT (CE-CT). MATERIALS AND METHODS: Both PD-US and CE-CT were performed in 99 cervical lymph nodes (LNs) with a maximum diameter of 1.5 cm or smaller and maximum longitudinal/transverse ratio of 1.5 or smaller in 76 patients with head and neck cancer. At pathologic examinations, 45 were reactive and 54 were metastatic LNs. The vascular patterns on PD-US were classified as hilar, avascular, peripheral, and miscellaneous vascular patterns. The enhancement patterns on CE-CT were classified as homogeneous, heterogeneous, and ring enhancement. RESULTS: On PD-US, the hilar pattern was more frequently associated with benignancy (91%) and the peripheral, miscellaneous vascular pattern with malignancy (91%). The avascular pattern included both benign (58%) and malignant (42%) LNs. On PD-US, accuracy was 85%. On CE-CT, ring enhancement showed metastasis (100%), and these LNs showed avascular or peripheral patterns on PD-US. On CE-CT, accuracy was 77%. When information on CE-CT results was added to PD-US results, the accuracy rate increased significantly, to 94% (p=0.01). CONCLUSION: Vascular patterns evaluated with PD-US and enhancement patterns on CE-CT can characterize SRLNs. For an avascular pattern on PD-US, information on CE-CT results can significantly increase the accuracy of characterization.     

Neue Ultraschalltechnologien f��r die Diagnostik des Prostatakarzinoms

Clinical/methodological issue

Prostate cancer is the most common cancer in men. The diagnosis is based on prostate-specific antigen (PSA), digital rectal examination (DRE) and transrectal ultrasound (TRUS) guided biopsy. These techniques have considerable limitations, which result in unnecessary biopsies. Furthermore the biopsies are associated with morbidity and costs.

Standard radiological methods

Standard gray-scale ultrasound has a low sensitivity and specificity for prostate cancer detection.

Methodological innovations

New ultrasound technologies, including color- and power Doppler ultrasound, contrast enhanced US and real-time sonoelastography have shown to improve prostate cancer diagnosis.

Performance

Contrast-enhanced ultrasound has shown a sensitivity of 100% (95% CI, 95%), a negative predictive value (NPV) of 99.8% and a positive predictive value (PPV) of 88.8% for prostate cancer detection. Real-time sonoelastography has shown a sensitivity of 86%, a specificity of 81% and NPV of 91% for prostate cancer diagnosis.

Achievements

Most studies show that these new ultrasound modalities demonstrate a 1.5 to 2.5 times higher detection of prostate cancer per biopsy specimen compared with systematic biopsy. Multicenter studies results are at present lacking but are, however ongoing.

Practical recommendations

In patients with suspected prostate cancer (elevated PSA, suspicious DRE) these new ultrasound techniques should be used. These techniques can detect prostate cancer and allow a targeted biopsy approach.