Imaging in gynecological disease (8): ultrasound characteristics of recurrent borderline ovarian tumors

OBJECTIVES

To describe the sonographic characteristics of borderline ovarian tumor (BOT) recurrence.

METHODS

From the databases of five ultrasound centers, we retrospectively identified 68 patients with histological diagnosis of recurrent BOT who had undergone preoperative ultrasound examination. All recurrences were detected during planned follow-up ultrasound examinations. Recurrent lesions were described using the terms and definitions of the International Ovarian Tumor Analysis (IOTA) group.

RESULTS

Sixty-two patients had a serous BOT recurrence and six a mucinous BOT recurrence. All patients except one were premenopausal, 84% of them being < 40 years old. All but one patient were asymptomatic at diagnosis of the recurrence. Fertility-sparing surgery of the recurrent tumor was performed in 57/68 (84%) patients. The most frequent ultrasound feature of recurrent serous BOT was a unilocular solid cyst (49/62, 79%) and almost half of the recurrent serous BOTs (29/62, 47%) had multiple papillary projections. In 89% of the recurrent serous BOTs there was at least one papillation with irregular surface and in 73% there was at least one papillation vascularized at color Doppler examination. Recurrent mucinous BOTs appeared mainly as multilocular or multilocular solid cysts (5/6, 83%).

CONCLUSION

Sonographic features of recurrent BOT resemble those described by others for different subtypes of primary BOT.

Tissue characterization using mean gray value analysis in deep infiltrating endometriosis

OBJECTIVES

To investigate differences in tissue characterization using three-dimensional sonographic mean gray value (MGV) between retrocervical and rectosigmoid deeply infiltrating endometriosis, and to assess intra- and interobserver concordance in MGV quantification.

METHODS

In this retrospective study, stored ultrasound volumes from 50 premenopausal women (mean age, 32 years) with 57 histologically confirmed nodules of deep endometriosis were retrieved from our database for analysis. A single experienced operator had acquired all volumes. For each nodule, the MGV was evaluated using virtual organ computer-aided analysis (VOCAL) software with semiautomated sphere-sampling (1 cm3) from the central part of the nodule. In these patients the MGV was also quantified from the myometrium of the fundal part of the uterus. In addition, two observers calculated the MGV in a subset of 24 volumes in order to quantify inter- and intraobserver agreement using intraclass correlation coefficients (ICC).

RESULTS

Mean MGV was significantly higher in rectosigmoid nodules (n = 34) than in nodules with a retrocervical location (n = 23) (23.863 vs. 17.705; P < 0.001). MGV of the myometrium was significantly higher in comparison with that of nodules in both locations (P < 0.001 for both). Intra- and interobserver measurement reproducibility was excellent (ICC > 0.95).

CONCLUSIONS

Retrocervical and rectosigmoid endometriotic nodules display significantly different MGVs. Measurement of MGV is highly reproducible and its clinical value in the diagnosis and assessment of distribution of deep endometriosis should be assessed in future studies.

Role of imaging in the management of endometriosis

The imaging techniques have a fundamental role in the diagnosis of endometriosis. Ovarian endometriosis (endometrioma) and deep endometriosis can be recognized using transvaginal ultrasound and/or magnetic resonance imaging (MRI). Although transvaginal ultrasound is the first choice of imaging modality when investigating women with pelvic pain, MRI have a role for the wider field of visions. The reproducibility of both techniques has been investigated. The three-dimensional ultrasonography has been proposed. Also studies regarding unusual localizations are reported in the literature. New insights are present about the role of imaging in the detection of the malignant transformations. This review summarizes the current evidence on the diagnostic accuracy of these two techniques in the pre-surgical assessment of endometriosis.

Risk of malignancy in unilocular cysts: a study of 1148 adnexal masses classified as unilocular cysts at transvaginal ultrasound and review of the literature

OBJECTIVES

The aim of this study was to estimate the rate of malignancy in adnexal lesions described as unilocular cysts at transvaginal ultrasound examination and to investigate if there are differences in clinical and ultrasound characteristics between benign and malignant unilocular cysts.

METHODS

A total of 3511 patients with an adnexal mass underwent transvaginal ultrasound examination between 1999 and 2007. Sonologists used the International Ovarian Tumor Analysis terms and definitions to describe their ultrasound findings. Only masses operated on within 120  days after the ultrasound examination were included in the analysis and the histopathological diagnosis of the mass was used as the gold standard.

RESULTS

Of the 3511 masses, 1148 (33%) were classified as unilocular cysts on ultrasound. Of these, 11 (0.96% (95% CI, 0.48-1.71)) were malignant. The malignancy rate was lower in premenopausal than in postmenopausal women: 0.54% (5/931; 95% CI, 0.17-1.25) vs. 2.76% (6/217; 95% CI, 1.02-5.92); P = 0.009. More patients with malignant unilocular cysts had a personal history of breast cancer (18% vs. 2%; P = 0.02) or ovarian cancer (18% vs 0.6%; P = 0.003). Hemorrhagic cyst contents on ultrasound were more common in malignant than in benign unilocular cysts (18% vs. 2%; P = 0.03). In seven of the 11 malignancies judged to be unilocular cysts at scan, papillary projections or other solid components were seen at macroscopic inspection of the surgical specimen.

CONCLUSIONS

The malignancy rate in surgically removed adnexal lesions judged to be unilocular cysts at transvaginal scan is c 1%. Postmenopausal status, personal history of breast or ovarian cancer and hemorrhagic cyst contents on ultrasound increase the risk of malignancy. To avoid misclassifying adnexal lesions as unilocular cysts at scan, it is important to scrutinize unilocular cysts for the presence of solid components.

Ovarian tumor characterization using 3D ultrasound

Among gynecological malignancies, ovarian cancer is the most frequent cause of death. Preoperative determination of whether a tumor is benign or malignant has often been found to be difficult. Because of such inconclusive findings from ultrasound images and other tests, many patients with benign conditions have been offered unnecessary surgeries thereby increasing patient anxiety and healthcare cost. The key objective of our work is to develop an adjunct Computer Aided Diagnostic (CAD) technique that uses ultrasound images of the ovary and image mining algorithms to accurately classify benign and malignant ovarian tumor images. In this algorithm, we extract texture features based on Local Binary Patterns (LBP) and Laws Texture Energy (LTE) and use them to build and train a Support Vector Machine (SVM) classifier. Our technique was validated using 1000 benign and 1000 malignant images, and we obtained a high accuracy of 99.9% using a SVM classifier with a Radial Basis Function (RBF) kernel. The high accuracy can be attributed to the determination of the novel combination of the 16 texture based features that quantify the subtle changes in the images belonging to both classes. The proposed algorithm has the following characteristics: cost-effectiveness, complete automation, easy deployment, and good end-user comprehensibility. We have also developed a novel integrated index, Ovarian Cancer Index (OCI), which is a combination of the texture features, to present the physicians with a more transparent adjunct technique for ovarian tumor classification.

Clinical and sonographic features of uncommon primary ovarian malignancies

PURPOSE

To describe the gray-scale and color Doppler ultrasound features of uncommon (<5% prevalence) primary malignant ovarian tumors.

METHODS

Retrospective analysis of 98 masses in 89 patients (median age: 50.4 years old, ranging from 15 to 81 years) diagnosed as having an uncommon primary ovarian malignancy. All patients had undergone transvaginal color Doppler ultrasound according to a standardized protocol prior to surgical tumor removal. Ultrasound features analyzed were laterality, presence of ascites, tumor volume, morphologic appearance (unilocular, multilocular, unilocular-solid, multilocular-solid, and solid), and color Doppler score (subjective assessment of the amount of flow as absent, scanty, moderate, or abundant).

RESULTS

Pathological diagnoses included uncommon epithelial tumors (n = 59), germ cell tumors (n = 10), sex cord-stromal tumors (n = 11), sarcoma (n = 9), and lymphoma (n = 9). Germ cell tumors presented in younger women (p < 0.001). Germ cell tumors, sex cord-stromal tumors, sarcomas, and lymphomas were significantly more often solid as compared with epithelial malignancies, which appeared more frequently as complex (cystic-solid) tumors (p < 0.001). There were no differences in color Doppler score between the various types of tumors.

CONCLUSIONS

Germ cell tumors, sex cord-stromal tumors, sarcomas, and lymphomas tend to appear as unilateral solid tumors. Color Doppler score is not useful for discriminating among uncommon primary ovarian malignancies.

Preoperative diagnosis of metastatic ovarian cancer is related to origin of primary tumor

OBJECTIVE

To describe the gray-scale and color Doppler ultrasound features as well as some clinical and biochemical features of metastatic ovarian tumors according to the origin of the primary tumor in a large study population,

METHODS

This was a retrospective analysis of 116 masses in 92 patients (mean age, 51 years) evaluated and treated at three European university centers for a metastatic tumor in the ovary. All patients had undergone transvaginal color Doppler ultrasound according to a standardized protocol prior to surgery and tumor removal. Ultrasound features analyzed were bilaterality, tumor volume, morphologic gray-scale appearance and color score. CA 125 was also recorded.

RESULTS

Primary tumor histological diagnosis was as follows: colon-sigmoid (n = 32), stomach (n = 28), breast (n = 20), uterus (n = 17), lymphoma (n = 4), liver-pancreas-biliary tract (n = 4) and miscellaneous (n = 11). There were no differences in age, menopausal status or CA 125 values according to origin of primary tumor. Bilaterality was significantly more frequent in stomach metastases (56%) in comparison with colon-sigmoid and liver-pancreas-biliary tract metastases (18.5% and 0%, respectively, P < 0.05). Median tumor volume was significantly lower in breast metastases (33.5 mL) compared with other metastases (P < 0.05) except stomach metastases and metastatic tumors from the miscellaneous group. Ovarian metastases from breast cancers were significantly more frequently solid in comparison to stomach, colorectal and uterine cancer metastases (95.0% vs. 60.8%, 46.8% and 70.6%, respectively, P < 0.05), and tended to appear moderately or highly vascularized. There were no differences in color score among all groups, although the percentage of masses with abundant color was high (50-82%).

CONCLUSIONS

Ovarian metastases derived from breast cancers tend to be small, solid and vascularized; they seem to be the only ovarian metastases whose primary tumor origin can be suspected by ultrasonography preoperatively. Color score does not seem to help suspect the origin of the primary tumor.

Extragenital endometrial stromal sarcoma arising in endometriosis

The diagnosis rate of deep pelvic endometriosis is increasing. Endometrial stromal sarcoma (ESS) is a rare neoplasm. Extragenital ESS is an extremely uncommon event. Very few cases of extragenital ESS have been reported to date. The diagnosis of this entity is very difficult in some instances. Knowledge about its management is also limited. In this paper, we review the current literature on the clinical management, histology, immunohistochemistry, treatment and outcome of ESS arising in pelvic endometriosis.

Ovarian tumor characterization and classification: a class of GyneScan™ systems

In this work, we have developed an adjunct Computer Aided Diagnostic (CAD) technique that uses 3D acquired ultrasound images of the ovary and data mining algorithms to accurately characterize and classify benign and malignant ovarian tumors. In this technique, we extracted image-texture based and Higher Order Spectra (HOS) based features from the images. The significant features were then selected and used to train and test the Decision Tree (DT) classifier. The proposed technique was validated using 1000 benign and 1000 malignant images, obtained from 10 patients with benign and 10 with malignant disease, respectively. On evaluating the classifier with 10-fold stratified cross validation, we observed that the DT classifier presented a high accuracy of 95.1%, sensitivity of 92.5% and specificity of 97.7%. Thus, the four significant features could adequately quantify the subtle changes and nonlinearities in the pixel intensities. The preliminary results presented in this paper indicate that the proposed technique can be reliably used as an adjunct tool for ovarian tumor classification since the system is accurate, completely automated, cost-effective, and can be easily written as a software application for use in any computer.

External validation of diagnostic models to estimate the risk of malignancy in adnexal masses

PURPOSE

To externally validate and compare the performance of previously published diagnostic models developed to predict malignancy in adnexal masses.

EXPERIMENTAL DESIGN

We externally validated the diagnostic performance of 11 models developed by the International Ovarian Tumor Analysis (IOTA) group and 12 other (non-IOTA) models on 997 prospectively collected patients. The non-IOTA models included the original risk of malignancy index (RMI), three modified versions of the RMI, six logistic regression models, and two artificial neural networks. The ability of the models to discriminate between benign and malignant adnexal masses was expressed as the area under the receiver operating characteristic curve (AUC), sensitivity, specificity, and likelihood ratios (LR(+), LR(-)).

RESULTS

Seven hundred and forty-two (74%) benign and 255 (26%) malignant masses were included. The IOTA models did better than the non-IOTA models (AUCs between 0.941 and 0.956 vs. 0.839 and 0.928). The difference in AUC between the best IOTA and the best non-IOTA model was 0.028 [95% confidence interval (CI), 0.011-0.044]. The AUC of the RMI was 0.911 (difference with the best IOTA model, 0.044; 95% CI, 0.024-0.064). The superior performance of the IOTA models was most pronounced in premenopausal patients but was also observed in postmenopausal patients. IOTA models were better able to detect stage I ovarian cancer.

CONCLUSION

External validation shows that the IOTA models outperform other models, including the current reference test RMI, for discriminating between benign and malignant adnexal masses.

MRI and "tenderness guided" transvaginal ultrasonography in the diagnosis of recto-sigmoid endometriosis

PURPOSE

To compare the diagnostic accuracy of MRI and "tenderness-guided" transvaginal ultrasonography (tg-TVUS) in the identification of recto-sigmoid endometriosis.

MATERIALS AND METHODS

Institutional Review Board approval for this study was obtained, and written informed consent was given by all patients. This study is compliant with the STARD (Standards for Reporting of Diagnostic Accuracy) method. Fifty-nine patients (mean age, 33 years; range, 21-44 years) with clinical suspicion of deep pelvic endometriosis were prospectively enrolled. They underwent tg-TVUS and MRI before surgery. The characteristics of the MRI signal were analyzed. Mapping of recto-sigmoid endometriosis was performed and tg-TVUS and MR imaging results were compared with surgical and pathological findings. Sensitivity, specificity, and the positive and negative likelihood ratio (LR+ and LR-) were calculated. Inter-technique concordance was assessed using the Cohen statistic, and receiver operating characteristic (ROC) curves were obtained. Logistic regression analysis was performed.

RESULTS

The prevalence of recto-sigmoid endometriosis was 51%. The specificity, sensitivity, and LR+ and LR- were 90%, 73%, 7.089 and 0.297, respectively, for MRI and 86%, 73%, 5.317 and 0.309, respectively, for tg-TVUS. The presence of a high T1 signal spot was an excellent specific finding (100%) but was associated with a low sensitivity (30%). Inter-technique concordance using the Cohen statistic indicated a kappa value of 0.658 (± 0.098 SD). According to the logistic regression equation obtained, the use of both tg-TVUS and MRI allows optimal diagnostic performance.

CONCLUSION

MRI and tg-TVUS show similar results in the identification of recto-sigmoid endometriosis. The Cohen kappa value suggests that these methods may have complementary roles in the identification of recto-sigmoid endometriosis, depending on the site affected.

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.

Adding cancer antigen 125 screening to gray scale sonography for predicting specific diagnosis of benign adnexal masses in premenopausal women: is it worthwhile?

OBJECTIVES

The purpose of this study was to assess whether a single determination of the serum cancer antigen 125 (CA-125) level provides additional information to sonography for specific diagnosis of benign adnexal masses in premenopausal women.

METHODS

We conducted a retrospective study comprising 1058 premenopausal women (mean age, 34.8 years) with histologically proven benign adnexal masses. All women had undergone transvaginal sonography and serum CA-125 determination within 1 week before surgery and tumor removal. According to "pattern recognition" analysis, a presumptive diagnosis was provided on gray scale transvaginal sonography for all masses. Positive and negative likelihood ratios were calculated for gray scale sonography and gray scale sonography plus CA-125.

RESULTS

Eighty-five women had bilateral masses (1143 masses analyzed). In 7 women with bilateral masses, the histologic diagnoses of the masses were discordant and were excluded. Histologic diagnoses were as follows: endometrioma, n = 452; dermoid cyst, n = 180; serous cyst, n = 158; hemorrhagic cyst, n = 119; mucinous cyst, n = 54; hydrosalpinx, n = 37; and other, n = 109. The median CA-125 level was significantly higher in endometrioma (71.9 IU/mL; range: 5-2620 IU/mL) and hydrosalpinx (59.2 IU/mL; range, 5-601 IU/mL) compared to all other tumor types (P < .001). The CA-125 level was 35 IU/mL or higher in 74% of endometriomas, 58% of hydrosalpinges, 34% of hemorrhagic cysts, 18% of mucinous cysts, 14% of dermoid cysts, and 8% of serous cysts. The positive and negative likelihood ratios for sonography and sonography plus CA-125 (335 IU/mL) for each kind of tumor were not statistically different except for endometrioma, for which the positive likelihood ratio for sonography plus CA-125 (55.0; 95% confidence interval, 27.5-109.9) was significantly higher than for sonography alone (19.2; 95% confidence interval, 13.6-27.1).

CONCLUSIONS

Cancer antigen 125 screening does not add useful information for specific diagnosis of benign adnexal tumors, except for endometrioma. An elevated CA-125 level significantly increases the probability of such a lesion.

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.

Autosomal recessive bestrophinopathy: new observations on the retinal phenotype - clinical and molecular report of an Italian family

PURPOSE

To describe the genotype and phenotype in a 9-year-old boy with bilateral retinopathy.

METHODS

The patient, his healthy (by history) nonconsanguineous parents and his sister were examined by best-corrected visual acuity, matrix frequency doubling technology, monocular static field analysis, fundus autofluorescence imaging, optical coherence tomography, Ganzfeld electroretinography (ERG), pattern ERG, multifocal ERG, electro-oculography and genotyping of the BEST1 gene.

RESULTS

The patient presented with an Arden ratio of 1.25, an unremarkable ERG and fluorescent yellow deposits distributed throughout the fundus suggestive of autosomal recessive bestrophinopathy (ARB). Genotyping revealed a homozygous nonsense mutation in BEST1 (p.R200X). The parents and the sister, who were heterozygous mutation carriers, presented with normal ophthalmological function.

CONCLUSIONS

ARB is a rare retinal disorder. We contribute a novel patient report indicative of ARB, assessed by clinical examination and confirmed by genotyping of BEST1, to the short list of ARB cases in the literature.

Orbital granular cell tumor in a patient with Churg Strauss syndrome: the importance of biopsy

A 65-year-old woman presented with a long standing, progressive exophthalmos of the right eye. Her medical history was significant for Churg Strauss syndrome, and was treated with immunosuppressive therapy. She had undergone two previous orbital biopsies showing inflammatory reactive lymphoid hyperplasia. A diagnosis of orbital inflammation in Churg-Strauss syndrome was suspected, and the immunosuppressive therapy was increased. Because of the lack of response to therapy, a further biopsy was performed, by lateral orbitotomy approach. Biopsy of the mass revealed a granular cell tumor composed of S-100 positive cells with an acidophilic granular cytoplasm and peripheral lymphocytic infiltration. A granular cell tumor, which is very rare in the orbit, should be considered in the differential diagnosis of orbital tumors, and if suspected, an excisional biopsy must be undertaken. Typical histopathological aspect of the granular cell tumor is characterized by the presence of S-100 positive closely packed polygonal cells with a granular cytoplasm.

Effect of cancer prevalence on the use of risk-assessment cut-off levels and the performance of mathematical models to distinguish malignant from benign adnexal masses

OBJECTIVE

Two logistic regression models have been developed for the characterization of adnexal masses. The goal of this prospective analysis was to see whether these models perform differently according to the prevalence of malignancy and whether the cut-off levels of risk assessment for malignancy by the models require modification in different centers.

METHODS

Centers were categorized into those with a prevalence of malignancy below 15%, between 15 and 30% and above 30%. The areas under the receiver-operating characteristics curves (AUC) were compared using bootstrapping. The optimal cut-off level of risk assessment for malignancy was chosen per center, corresponding to the highest sensitivity level possible while still keeping a good specificity.

RESULTS

Both models performed better in centers with a lower prevalence of malignant cases. The AUCs of the two models for centers with fewer than 15% malignant cases were 0.97 and 0.95, those of centers with 15-30% malignancy were 0.95 and 0.93 and those of centers with more than 30% malignant cases were 0.94 and 0.92. This decrease in performance was due mainly to the decrease in specificity from over 90 to around 76%. In the centers with a higher percentage of malignant cases, a sensitivity of at least 90% with a good specificity could not be obtained by choosing a different cut-off level.

CONCLUSIONS

Overall the models performed well in all centers. The performance of the logistic regression models worsened with increasing prevalence of malignancy, due to a case mix with more borderline and complex benign masses seen in those centers. Because the cut-off of 0.10 is optimal for all three types of center, it seems reasonable to use this cut-off for both models in all centers.

The diagnosis of ovarian cancer: is color Doppler imaging reproducible and accurate in examiners with different degrees of experience?

OBJECTIVE

To evaluate the reproducibility and accuracy of color Doppler flow location in indeterminate masses after a gray-scale sonography in the diagnosis of ovarian malignancy.

METHODS

Digitally stored color Doppler sonographic images from a random sample of 130 women with an indeterminate adnexal mass submitted to surgery were evaluated by six different examiners with different degrees of experience. A mass was graded malignant if flow was shown within the excrescences or solid areas. Intraobserver agreement and interobserver agreement according to the level of experience were assessed by calculating the kappa index.

RESULTS

Intraobserver agreement was good for all examiners with different degrees of experience (kappa 0.72-0.89). Interobserver agreement was good to moderate for all operators (kappa 0.48-0.71) irrespective of degree of experience. The accuracy was comparable among different operators.

CONCLUSIONS

Our results indicate that color Doppler imaging for detection of adnexal malignancy seems to be a reproducible method even in moderately experienced examiners.