Contribution of morphological assessment of the vessel tree by three-dimensional ultrasound to a correct diagnosis of malignancy in ovarian masses

Ultrasound evaluation of ovarian masses and assessment of the extension of ovarian malignancy

The current review sums up the literature on the diagnostic performance of models to predict malignancy in adnexal masses and the ability of ultrasound to make a specific diagnosis in adnexal masses. A summary of the role of ultrasound in assessing the extension of malignant ovarian disease is also provided.

Vessel morphology depicted by three-dimensional power Doppler ultrasound as second-stage test in adnexal tumors that are difficult to classify: prospective diagnostic accuracy study

OBJECTIVES

To assess whether vessel morphology depicted by three-dimensional (3D) power Doppler ultrasound improves discrimination between benignity and malignancy if used as a second-stage test in adnexal masses that are difficult to classify.

METHODS

This was a prospective observational international multicenter diagnostic accuracy study. Consecutive patients with an adnexal mass underwent standardized transvaginal two-dimensional (2D) grayscale and color or power Doppler and 3D power Doppler ultrasound examination by an experienced examiner, and those with a 'difficult' tumor were included in the current analysis. A difficult tumor was defined as one in which the International Ovarian Tumor Analysis (IOTA) logistic regression model-1 (LR-1) yielded an ambiguous result (risk of malignancy, 8.3% to 25.5%), or as one in which the ultrasound examiner was uncertain regarding classification as benign or malignant when using subjective assessment. Even when the ultrasound examiner was uncertain, he/she was obliged to classify the tumor as most probably benign or most probably malignant. For each difficult tumor, one researcher created a 360° rotating 3D power Doppler image of the vessel tree in the whole tumor and another of the vessel tree in a 5-cm³ spherical volume selected from the most vascularized part of the tumor. Two other researchers, blinded to the patient's history, 2D ultrasound findings and histological diagnosis, independently described the vessel tree using predetermined vessel features. Their agreed classification was used. The reference standard was the histological diagnosis of the mass. The sensitivity of each test for discriminating between benign and malignant difficult tumors was plotted against 1 - specificity on a receiver-operating-characteristics diagram, and the test with the point furthest from the reference line was considered to have the best diagnostic ability.

RESULTS

Of 2403 women with an adnexal mass, 376 (16%) had a difficult mass. Ultrasound volumes were available for 138 of these cases. In 79/138 masses, the ultrasound examiner was uncertain about the diagnosis based on subjective assessment, in 87/138, IOTA LR-1 yielded an ambiguous result and, in 28/138, both methods gave an uncertain result. Of the masses, 38/138 (28%) were malignant. Among tumors that were difficult to classify as benign or malignant by subjective assessment, the vessel feature 'densely packed vessels' had the best discriminative ability (sensitivity 67% (18/27), specificity 83% (43/52)) and was slightly superior to subjective assessment (sensitivity 74% (20/27), specificity 60% (31/52)). In tumors in which IOTA LR-1 yielded an ambiguous result, subjective assessment (sensitivity 82% (14/17), specificity 79% (55/70)) was superior to the best vascular feature, i.e. changes in the diameter of vessels in the whole tumor volume (sensitivity 71% (12/17), specificity 69% (48/70)).

CONCLUSION

Vessel morphology depicted by 3D power Doppler ultrasound may slightly improve discrimination between benign and malignant adnexal tumors that are difficult to classify by subjective ultrasound assessment. For tumors in which the IOTA LR-1 model yields an ambiguous result, subjective assessment is superior to vessel morphology as a second-stage test. © 2020 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.

Past, present and future ultrasonographic techniques for analyzing ovarian masses

Ultrasonography is today the method of choice for distinguishing between benign and malignant adnexal pathologies. Using pattern recognition several types of tumors can be recognized according to their characteristic appearance on gray-scale imaging. Color Doppler imaging should be used only to perform a semiquantitative color score or evaluate the flow location. International Ovarian Tumor Analysis group had standardized definitions characterizing adnexal masses and suggested the use of 'simple rules' in premenopausal women. Recently, the use of 3D vascular indices has been proposed but its potential use in clinical practice is debated. Also computerized aided diagnosis algorithms showed encouraging results to be confirmed in the future.

Management of epithelial ovarian cancer from diagnosis to restaging: an overview of the role of imaging techniques with particular regard to the contribution of 18F-FDG PET/CT

Epithelial ovarian carcinoma is a major form of cancer affecting women in the western world. The silent nature of this disease results in late presentation at an advanced stage in many patients. It is therefore important to assess the role of imaging techniques in the management of these patients. This article presents a review of the literature on the role of (18)F-FDG-PET/CT in the different stages of management of epithelial ovarian cancer. Moreover, a comparison with other imaging techniques has been made and the relationship between (18)F-PET/CT and the assay of serum CA-125 levels has been discussed.

Assessing repeatability of 3D Doppler indices obtained by static 3D and STIC power Doppler: a combined in-vivo/in-vitro flow phantom study

OBJECTIVES

To compare the variability in vascularization flow index (VFI) seen in serial acquisitions obtained using spatiotemporal image correlation (STIC) and using conventional static three-dimensional (3D) power Doppler (PD), for both in-vitro and in-vivo models, and to evaluate whether the curves formed by VFI values obtained from successive 'frames' in a STIC dataset are consistent and resemble the waveforms obtained by spectral Doppler analysis.

METHODS

The study was divided into two parts: in the first part (the in-vitro model) we scanned a flow phantom, while in the second part (the in-vivo model) we scanned a common carotid artery. Conventional static 3D and STIC-PD datasets were alternately acquired from these two models. VFI values were assessed from 0.38-cm(3) spherical samples of the main flow region in the static 3D datasets and in every frame of the STIC datasets. The variance of the minimum, mean and maximum VFI values from each STIC dataset was compared with the variance of VFI values from the static 3D datasets.

RESULTS

Ten static 3D and 10 STIC datasets were acquired from each model. Analysis of the in-vitro and in-vivo models showed a significant reduction in the variance of VFI values obtained using STIC as compared to static datasets. Additionally, we observed that the curves formed by VFI values obtained from successive frames in each STIC dataset were consistent across different datasets and that they resembled the waveforms obtained by spectral Doppler in both models.

CONCLUSIONS

3D-PD indices derived from STIC are more stable than those obtained from conventional static 3D-PD datasets. The curves of VFI throughout a reconstructed cardiac cycle using STIC are repeatable and resemble those obtained by spectral Doppler analysis of the vessel.

Unilocular adnexal cysts with papillary projections but no other solid components: is there a diagnostic method that can classify them reliably as benign or malignant before surgery?

OBJECTIVES

To develop a logistic regression model for discrimination between benign and malignant unilocular solid cysts with papillary projections but no other solid components, and to compare its diagnostic performance with that of subjective evaluation of ultrasound findings (subjective assessment), CA  125 and the risk of malignancy index (RMI).

METHODS

Among the 3511 adnexal masses in the International Ovarian Tumor Analysis (IOTA) database there were 252 (7%) unilocular solid cysts with papillary projections but no other solid components ('unilocular cysts with papillations'). All had been examined with transvaginal ultrasound using the IOTA standardized research protocol. The ultrasound examiner had also classified each mass as certainly or probably benign, unclassifiable, or certainly or probably malignant. A logistic regression model to discriminate between benignity and malignancy was developed for all unilocular cysts with papillations (175 tumors in the training set and 77 in the test set) and for unilocular cysts with papillations for which the ultrasound examiner was not certain about benignity/malignancy (113 tumors in the training set and 53 in the test set). The gold standard was the histological diagnosis of the surgically removed adnexal mass.

RESULTS

A model containing six variables was developed for all unilocular cysts with papillations. The model had an area under the receiver-operating characteristics curve (AUC) on the test set of 0.83 (95% CI, 0.74-0.93). The optimal risk cut-off, as defined on the training set (0.35), resulted in sensitivity 69% (20/29), specificity 79% (38/48), positive likelihood ratio (LR +) 3.31 and negative likelihood ratio (LR-) 0.39 on the test set. The corresponding values for subjective assessment when using the ultrasound examiner's dichotomous classification of the mass as benign or malignant were 97% (28/29), 79% (38/48), 4.63 and 0.04. A model containing four variables was developed for unilocular cysts with papillations for which the ultrasound examiner was not certain about benignity/malignancy. The model had an AUC of 0.74 (95% CI, 0.60-0.88) on the test set. The optimal risk cut-off of the model, as defined on the training set (0.30), resulted in sensitivity 57% (12/21), specificity 78% (25/32), LR + 2.61 and LR- 0.55 on the test set. The corresponding values for subjective assessment were 95% (20/21), 78% (25/32), 4.35 and 0.06. CA  125 and RMI had virtually no diagnostic ability.

CONCLUSIONS

Even though logistic regression models to predict malignancy in unilocular cysts with papillations can be developed, they have at most moderate performance and are not superior to subjective assessment for discrimination between benignity and malignancy.

Intra- and interobserver agreement when describing adnexal masses using the International Ovarian Tumor Analysis terms and definitions: a study on three-dimensional ultrasound volumes

OBJECTIVES

To estimate intraobserver repeatability and interobserver agreement in: (1) describing adnexal masses using the International Ovarian Tumor Analysis (IOTA) terms and definitions; (2) the risk of malignancy calculated using IOTA logistic regression model 1 (LR1) and model 2 (LR2); and (3) the diagnosis made on the basis of subjective assessment of ultrasound images.

METHODS

One-hundred and three adnexal masses were examined by transvaginal gray-scale and power Doppler ultrasound. Three-dimensional ultrasound volumes of the mass were saved. After 12-18 months the volumes were analyzed twice, 1-6 months apart, by each of two independent experienced sonologists who used the IOTA terms and definitions to describe the masses. The risk of malignancy was calculated using LR1 and LR2. The sonologists also classified the masses as benign or malignant using subjective assessment.

RESULTS

Eighty-four masses were benign, eight were borderline and 11 were invasively malignant. There was substantial variability within and between observers in the results of measurements included in LR1 and LR2 and some variability also when assessing categorical variables included in the models (agreement = 51-100% and kappa = 0.42-1.00). This resulted in substantial variability in the calculated risk of malignancy, the limits of agreement indicating that the calculated risk of malignancy could vary by a factor of 5-20 within and between observers. The reliability of the calculated risk of malignancy was moderate (LR1) or poor (LR2) when the calculated risk of malignancy was > 10% (intraclass correlation coefficients varied from 0.21 to 0.73). Interobserver agreement when classifying tumors as benign or malignant using the predetermined risk of malignancy cut-off of 10% was fair to good (agreement = 85% and kappa = 0.61 for LR1; agreement = 81% and kappa = 0.52 for LR2). Intra- and interobserver agreements for subjective assessment were 96%, 96% and 96% with kappa values of 0.89, 0.87 and 0.88, respectively.

CONCLUSIONS

Intra- and interobserver agreement in classifying tumors as benign or malignant using the risk of malignancy cut-off of 10% for LR1 and LR2 was fair or good, whilst the reproducibility of subjective assessment was excellent. The reliability of calculated risks > 10% was poor, and calculated risk > 10% cannot be used to discriminate between individuals at different risk. These results cannot be extrapolated to real-time ultrasound examinations.

Improving strategies for diagnosing ovarian cancer: a summary of the International Ovarian Tumor Analysis (IOTA) studies

In order to ensure that ovarian cancer patients access appropriate treatment to improve the outcome of this disease, accurate characterization before any surgery on ovarian pathology is essential. The International Ovarian Tumor Analysis (IOTA) collaboration has standardized the approach to the ultrasound description of adnexal pathology. A prospectively collected large database enabled previously developed prediction models like the risk of malignancy index (RMI) to be tested and novel prediction models to be developed and externally validated in order to determine the optimal approach to characterize adnexal pathology preoperatively. The main IOTA prediction models (logistic regression model 1 (LR1) and logistic regression model 2 (LR2)) have both shown excellent diagnostic performance (area under the curve (AUC) values of 0.96 and 0.95, respectively) and outperform previous diagnostic algorithms. Their test performance almost matches subjective assessment by experienced examiners, which is accepted to be the best way to classify adnexal masses before surgery. A two-step strategy using the IOTA simple rules supplemented with subjective assessment of ultrasound findings when the rules do not apply, also reached excellent diagnostic performance (sensitivity 90%, specificity 93%) and misclassified fewer malignancies than did the RMI. An evidence-based approach to the preoperative characterization of ovarian and other adnexal masses should include the use of LR1, LR2 or IOTA simple rules and subjective assessment by an experienced examiner.

Evaluation of selected ultrasonographic parameters and marker levels in the preoperative differentiation of borderline ovarian tumors and ovarian cancers

Abstract

Objectives

In young patients with borderline tumors the fertility-sparing treatment is indicated, thus the preoperative investigation is important. The aim of this study was to perform a comparative assessment of sensitivity and specificity of selected ultrasonographic and clinical parameters for the diagnoses of borderline tumors and ovarian cancers.

Methods

We retrospectively analyzed 57 patients who underwent surgical treatment in the Maria Sklodowska-Curie Memorial Cancer Center from Jan 01, 2008 to Dec 31, 2009. Ovarian cancers were diagnosed in 41 patients, and borderline ovarian tumors in 16 patients. Statistical model was developed to determine independent predictive factors that would be useful in preoperative differentiation between both tumors. The model included the following factors: menopausal status, tumor morphology, wall thickness (including outgrowths), septal thickness, echogenicity, resistive index, serum CA-125 level, and free fluid in the peritoneal cavity.

Results

Based on the statistical model developed, independent predictive factors in the differentiation between ovarian cancers and borderline tumors included the menopausal status (P = 0.005), tumor echogenicity (P = 0.047) and the presence of free fluid in the Douglas pouch (P = 0.043). With the cutoff value of 13 (with scores below 13 indicating a borderline ovarian tumor, and scores of ≥13 indicating ovarian cancer), sensitivity was 90.2 % and specificity was 87 %.

Conclusions

Our proposed model of preoperative evaluation has a sensitivity of 90 % in the differentiation between ovarian cancers and borderline tumors. When combined with intraoperative findings, it allows optimal surgical therapeutic decisions to be made in patients with borderline ovarian tumors.

Adnexal masses difficult to classify as benign or malignant using subjective assessment of gray-scale and Doppler ultrasound findings: logistic regression models do not help

OBJECTIVE

To develop a logistic regression model that can discriminate between benign and malignant adnexal masses perceived to be difficult to classify by subjective evaluation of gray-scale and Doppler ultrasound findings (subjective assessment) and to compare its diagnostic performance with that of subjective assessment, serum CA 125 and the risk of malignancy index (RMI).

METHODS

We used data from the 3511 patients with an adnexal mass included in the International Ovarian Tumor Analysis (IOTA) studies. All patients had been examined using transvaginal gray-scale and Doppler ultrasound following a standardized research protocol carried out by an experienced ultrasound examiner using a high-end ultrasound system. In addition to prospectively collecting information on > 40 clinical and ultrasound variables, the ultrasound examiner classified each mass as certainly or probably benign, unclassifiable, or certainly or probably malignant. A logistic regression model to discriminate between benignity and malignancy was developed for the unclassifiable masses (n = 244, i.e. 7% of all tumors) using a training set (160 tumors, 45 malignancies) and then tested on a test set (84 tumors, 28 malignancies). The gold standard was the histological diagnosis of the surgically removed adnexal mass. The area under the receiver-operating characteristics curve (AUC), sensitivity, specificity, positive likelihood ratio (LR+) and negative likelihood ratio (LR-) were used to describe diagnostic performance and were compared between subjective assessment, CA 125, the RMI and the logistic regression model created.

RESULTS

One variable was retained in the logistic regression model: the largest diameter (in mm) of the largest solid component of the tumor (odds ratio (OR) = 1.04; 95% CI, 1.02-1.06). The model had an AUC of 0.68 (95% CI, 0.59-0.78) on the training set and an AUC of 0.65 (95% CI, 0.53-0.78) on the test set. On the test set, a cut-off of 25% probability of malignancy (corresponding to the largest diameter of the largest solid component of 23 mm) resulted in a sensitivity of 64% (18/28), a specificity of 55% (31/56), an LR+ of 1.44 and an LR- of 0.65. The corresponding values for subjective assessment were 68% (19/28), 59% (33/56), 1.65 and 0.55. On the test set of patients with available CA 125 results, the LR+ and LR- of the logistic regression model (cut-off = 25% probability of malignancy) were 1.29 and 0.73, of subjective assessment were 1.45 and 0.63, of CA 125 (cut-off = 35 U/mL) were 1.24 and 0.84 and of RMI (cut-off = 200) were 1.21 and 0.92.

CONCLUSIONS

About 7% of adnexal masses that are considered appropriate for surgical removal cannot be classified as benign or malignant by experienced ultrasound examiners using subjective assessment. Logistic regression models to estimate the risk of malignancy, CA 125 measurements and the RMI are not helpful in these masses.

Imaging of gynecological disease (6): clinical and ultrasound characteristics of ovarian dysgerminoma

OBJECTIVES

To describe the clinical history and ultrasound findings in patients with ovarian dysgerminoma.

METHODS

This was a retrospective study of patients with a histological diagnosis of ovarian dysgerminoma who had undergone preoperative ultrasound examination. The patients were identified from the databases of 11 ultrasound centers. The tumors were described by the principal investigator at each contributing center on the basis of ultrasound images, ultrasound reports and research protocols (when applicable) using the terms and definitions of the International Ovarian Tumor Analysis (IOTA) group. In addition, three authors reviewed all available electronic ultrasound images (gray-scale images and color/power Doppler images were available for 18 patients and 14 patients, respectively) and described them using subjective evaluation of gray-scale and color Doppler ultrasound findings (here called pattern recognition).

RESULTS

Twenty-one patients with ovarian dysgerminoma were identified (including one woman with bilateral masses). Twenty patients had a primary ovarian dysgerminoma (including the one with bilateral masses) and one patient had a recurrence of dysgerminoma in her retained ovary. One of the 21 patients was pregnant. All tumors except one were pure dysgerminomas, one being a mixed germinal cell tumor with 30% dysgerminoma component. Median age was 20 (range, 16-31) years. Information on clinical symptoms was available for 18 patients. In four patients, the tumor was detected incidentally, whereas 14 patients presented with one or more of the following symptoms: acute pain (n = 4), chronic pain (n = 8), bloating (n = 8), menstrual disorders (n = 5) and infertility problems (n = 1). One (5%) patient had ascites. Using the IOTA terms and definitions, all but one dysgerminoma were moderately (43%) or very well (50%) vascularized solid tumors. One tumor was multilocular-solid. According to pattern recognition, most dysgerminomas were highly vascularized, purely solid tumors with heterogeneous internal echogenicity divided into several lobules, had a smooth and sometimes lobulated contour and were well-defined relative to the surrounding organs.

CONCLUSION

The ultrasound finding of a highly vascularized, large, solid, lobulated adnexal mass with irregular internal echogenicity in a woman 20-30 years old should raise the suspicion of ovarian dysgerminoma.

Improving the preoperative classification of adnexal masses as benign or malignant by second-stage tests

OBJECTIVE

The aim of this study was to establish when a second-stage diagnostic test may be of value in cases where a primary diagnostic test has given an uncertain diagnosis of the benign or malignant nature of an adnexal mass.

METHODS

The diagnostic performance with regard to discrimination between benign and malignant adnexal masses for mathematical models including ultrasound variables and for subjective evaluation of ultrasound findings by an experienced ultrasound examiner was expressed as area under the receiver-operating characteristics curve (AUC), sensitivity and specificity. These were calculated for the total study population of 1938 patients with an adnexal mass as well as for subpopulations defined by the certainty with which the diagnosis of benignity or malignancy was made. The effect of applying a second-stage test to the tumors where risk estimation was uncertain was determined.

RESULTS

The best mathematical model (LR1) had an AUC of 0.95, sensitivity of 92% and specificity of 84% when applied to all tumors. When model LR1 was applied to the 10% of tumors in which the calculated risk fell closest to the risk cut-off of the model, the AUC was 0.59, sensitivity 90% and specificity 21%. A strategy where subjective evaluation was used to classify these 10% of tumors for which LR1 performed poorly and where LR1 was used in the other 90% of tumors resulted in a sensitivity of 91% and specificity of 90%. Applying subjective evaluation to all tumors yielded an AUC of 0.95, sensitivity of 90% and specificity of 93%. Sensitivity was 81% and specificity 47% for those patients where the ultrasound examiner was uncertain about the diagnosis (n = 115; 5.9%). No mathematical model performed better than did subjective evaluation among the 115 tumors where the ultrasound examiner was uncertain.

CONCLUSION

When model LR1 is used as a primary test for discriminating between benign and malignant adnexal masses, the use of subjective evaluation of ultrasound findings by an experienced examiner as a second-stage test in the 10% of cases for which the model yields a risk of malignancy closest to its risk cut-off will improve specificity without substantially decreasing sensitivity. However, none of the models tested proved suitable as a second-stage test in tumors where subjective evaluation yielded an uncertain result.

Brain perfusion heterogeneity measurement based on Random Walk algorithm: choice and influence of inner parameters

A Random Walk (RW) algorithm was designed to quantify the level of diffuse heterogeneous perfusion in brain SPECT images in patients suffering from systemic brain disease or from drug-induced therapy. The goal of the present paper is to understand the behavior of the RW method on different kinds of images (extrinsic parameters) and also to understand how to choose the right parameters of the RW (intrinsic parameters) depending on the image characteristics (i.e. SPECT images). "Extrinsic parameters" are related to the image characteristics (level/size of defect and diffuse heterogeneity) and "intrinsic" parameters are related to the parameters of the method (number (N(rw)) and length of walk (L(rw)), temperature (T) and slowing parameter (S)). Two successive studies were conducted to test the influence of these parameters on the RW result. In the first study, calibrated checkerboard images are used to test the influence of "extrinsic parameters" (i.e. image characteristics) on the RW result (R-value). The R-value was tested as a function of (i) the size of black & white (B&W) squares simulating the size of a cortical defect, (ii) the intensity level gaps between the B&W squares simulating the intensity of the cortical defect and (iii) intensity (=variance) of noise, simulating the diffuse heterogeneity. The second study was constructed with simulated representative brain SPECT images, to test the "intrinsic" parameters. The R-value was tested regarding the influence of four parameters: S, T, N(rw) and L(rw). The third study is constructed so as to see if the classification by diffuse heterogeneity of real brain SPECT images is the same if it's made by senior clinicians or by RW algorithm.

RESULTS

Study 1: the RW was strongly influenced by all the characteristics of the images. Moreover, these characteristics interact with each other. The RW is influenced most by diffuse heterogeneity, then by intensity and finally by the size of a defect. Study 2: N(rw) and L(rw) values of 1000 give an optimal reproducibility of the measurement (mean standard deviation<0.1), a fast computation time (time<0.5s/image) and have a maximum difference in terms of R-value between the two extreme images corresponding to the range of the population studied. The best S and T values for SPECT images are 3 and 15, respectively. Study 3: A significant correlation was found between RW ranking and the physicians' consensus (rho=0.789; p<0.0001).

CONCLUSION

This study confirms that the RW method is able to measure the heterogeneity of brain SPECT images even in the presence of a large defect. However, the result of the method is strongly influenced by the "intrinsic" parameters, so the program should be calibrated for each different type of image.

Adding a single CA 125 measurement to ultrasound imaging performed by an experienced examiner does not improve preoperative discrimination between benign and malignant adnexal masses

OBJECTIVES

To determine whether CA 125 measurement is superior to ultrasound imaging performed by an experienced examiner for discriminating between benign and malignant adnexal lesions, and to determine whether adding CA 125 to ultrasound examination improves diagnostic performance.

METHODS

This is a prospective multicenter study (International Ovarian Tumor Analysis (IOTA) study) conducted in nine European ultrasound centers in university hospitals. Of 1149 patients with an adnexal mass examined in the IOTA study, 83 were excluded. Of the remaining 1066 patients, 809 had CA 125 results available and were included. The patients underwent preoperative serum CA 125 measurements and transvaginal ultrasound examination by an experienced ultrasound examiner blinded to CA 125 values. The examiner classified each mass as certainly or probably benign, difficult to classify, or probably or certainly malignant. The outcome measure was the sensitivity and specificity with regard to malignancy of CA 125, ultrasound imaging and their combined use, the 'gold standard' being the histological diagnosis of the adnexal mass removed surgically within 120 days after the ultrasound examination.

RESULTS

There were 242 (30%) malignancies. For 534 tumors judged to be certainly benign or certainly malignant by the ultrasound examiner the sensitivity and specificity of ultrasound examination and CA 125 (> or =35 U/mL indicating malignancy) were 97% vs. 86% (95% CI of difference, 4.7-17.2) and 99% vs. 79% (95% CI of difference, 15.7-24.2); for 209 tumors judged probably benign or probably malignant, sensitivity and specificity were 81% vs. 57% (95% CI of difference, 12.3-36.0) and 91% vs. 74% (95% CI of difference, 8.5-25.7); for 66 tumors that were difficult to classify, sensitivity and specificity were 57% vs. 39% (95% CI of difference, -9.7 to 41.1) and 74% vs. 67% (95% CI of difference, -14.6 to 27.7). Diagnostic performance deteriorated when CA 125 was used as a second-stage test after ultrasound examination.

CONCLUSIONS

Specialist ultrasound examination is superior to CA 125 for preoperative discrimination between benign and malignant adnexal masses, irrespective of the diagnostic confidence of the ultrasound examiner; adding CA 125 to ultrasound does not improve diagnostic performance. Our results indicate that greater investment in education and training in gynecological ultrasound imaging would be of value.

Preoperative diagnosis of ovarian malignancy: preliminary results of the use of 3-dimensional vascular ultrasound

OBJECTIVE

To estimate the accuracy of 3-dimensional (3D) vascular ultrasound in the preoperative assessment of pelvic masses for malignancy.

METHODS

We performed a chart review of 66 patients who underwent 3D ultrasound for pelvic masses. Each mass was preoperatively judged to be benign or malignant based upon a study of vascularity within an ovarian mass using 3D ultrasound. Masses with orderly vascular architecture were categorized as probably benign, and masses with chaotic vascular patterns were categorized as malignant. The predictive value of 3D vascular ultrasound was compared with that of 2-dimensional ultrasound and cancer antigen 125 as a predictor of malignancy.

RESULTS

Among the 66 patients examined, 34 underwent a documented surgical intervention. Of those 34 patients, 10 had primary malignant neoplasms including 2 with low-malignant potential tumors. Suspicious 3D vascular ultrasound findings predicted malignant neoplasm in 10 patients. Two patients had recurrent cancer; however, only 1 had a suspicious ultrasound finding. There was 1 case of a low-malignant potential tumor without a suspicious ultrasound finding. Excluding the recurrent cancers and the observed patients, the positive predictive value (PPV) and the negative predictive value (NPV) of 3D vascular ultrasound were 100% and 95%, respectively. The PPV and the NPV of 2-dimensional ultrasound in predicting malignancy were 37% and 100%, respectively. An abnormal level of cancer antigen 125 had a PPV and an NPV of 73% and 83%, respectively, in this patient population.

CONCLUSIONS

In this preliminary and observational study, 3D ultrasound examination of vascular architecture was discriminatory in distinguishing benign ovarian masses from malignancy. Chaotic vascular architecture correlated with malignancy in this group of high-risk patients.

3D Ultrasound in Gynecology and Reproductive Medicine

With advances occurring in medicine on a daily basis, it was only a matter of time before essential gynecological investigations, such as ultrasound, were modified. Many clinicians remain unconvinced by its reputed advantages and 3D ultrasound is not without disadvantages. These mainly relate to the cost implications and training requirements. 3D ultrasound imaging is still at a relatively early stage in terms of its role as a day-to-day imaging modality in gynecology and reproductive medicine. 3D imaging has several obvious benefits that relate to an improved spatial orientation and the demonstration of multiplanar views, of which the coronal plane is particularly useful. It offers a more objective and reproducible measurement of volume and vascularity of the region of interest, and an improved assessment of normal and pathological pelvic organs through further postprocessing modalities, including tomographic ultrasound imaging and various rendering modalities. It also has the benefit of offering reduced scanning time, the option of teleconsultation and storage of images for re-evaluation. However, other than its application in the assessment and differentiation of uterine anomalies, there is very little evidence demonstrating that 3D ultrasound results in a clinically relevant benefit or negates the need for further investigation. Future work should ensure that 3D ultrasound is compared with conventional imaging in randomized trials where the observer is blind to the outcome, only after which will we truly be able to evaluate its role in an evidence-based manner.

Three-dimensional power Doppler vascular network assessment of adnexal masses: intraobserver and interobserver agreement analysis

OBJECTIVE

The purpose of this study was to assess intraobserver and interobserver agreement for tumor vascular network evaluation as assessed by 3-dimensional (3D) power Doppler sonography for discriminating benign from malignant adnexal masses.

METHODS

Stored 3D power Doppler angiographic volume data from 39 women with a diagnosis of a vascularized adnexal mass who were evaluated and treated at our institution were retrieved from our database for analysis. Two different examiners (observer A, with 6 years of experience in 3D sonography; and observer B, with 1 year of experience) reviewed 3D sonograms blinded to each other. Three-dimensional vascular network reconstruction was done with surface rendering in the color mode. Malignancy was considered in the presence of at least 2 of the following: irregular branching, vessel caliber changes, microaneurysms, and vascular lakes. A definitive histologic diagnosis was obtained in all cases. Intraobserver and interobserver agreement rates were estimated by calculating the kappa index.

RESULTS

Twenty (51%) tumors were malignant, and 19 (49%) were benign. Intraobserver agreement was good for observer A (kappa = 0.69) and moderate for observer B (kappa = 0.54). Interobserver agreement was moderate (kappa = 0.49).

CONCLUSIONS

We found intraobserver and interobserver agreement to be moderate for 3D power Doppler assessment of the vascular network in adnexal masses.