Differential diagnosis of adnexal masses: sequential use of the risk of malignancy index and HistoScanning, a novel computer-aided diagnostic tool

Analysis of computer-aided diagnostics in the preoperative diagnosis of ovarian cancer: a systematic review

OBJECTIVES

Different noninvasive imaging methods to predict the chance of malignancy of ovarian tumors are available. However, their predictive value is limited due to subjectivity of the reviewer. Therefore, more objective prediction models are needed. Computer-aided diagnostics (CAD) could be such a model, since it lacks bias that comes with currently used models. In this study, we evaluated the available data on CAD in predicting the chance of malignancy of ovarian tumors.

METHODS

We searched for all published studies investigating diagnostic accuracy of CAD based on ultrasound, CT and MRI in pre-surgical patients with an ovarian tumor compared to reference standards.

RESULTS

In thirty-one included studies, extracted features from three different imaging techniques were used in different mathematical models. All studies assessed CAD based on machine learning on ultrasound, CT scan and MRI scan images. Per imaging method, subsequently ultrasound, CT and MRI, sensitivities ranged from 40.3 to 100%; 84.6-100% and 66.7-100% and specificities ranged from 76.3-100%; 69-100% and 77.8-100%. Results could not be pooled, due to broad heterogeneity. Although the majority of studies report high performances, they are at considerable risk of overfitting due to the absence of an independent test set.

CONCLUSION

Based on this literature review, different CAD for ultrasound, CT scans and MRI scans seem promising to aid physicians in assessing ovarian tumors through their objective and potentially cost-effective character. However, performance should be evaluated per imaging technique. Prospective and larger datasets with external validation are desired to make their results generalizable.

Usefulness of repeat pelvic ultrasonography before surgery for benign ovarian mass

OBJECTIVE

To evaluate the results of repeat pelvic ultrasonography before surgery in patients with suspicion of benign ovarian tumor.

METHODS

A retrospective study included premenopausal women who were scheduled to undergo surgery for a benign-appearing ovarian mass and who had repeat ultrasonography on the day before surgery at Samsung Medical Center, Seoul, South Korea, between January 1, 2007, and December 31, 2011, to check for any change in the mass. Ultrasonography findings and final histology were evaluated by medical record review.

RESULTS

Of 1854 women studied, regression of mass was detected before surgery for 27 patients, and 105 patients had histologically proven functional cysts; considered together, 132 patients had functional cysts, and the remaining 1722 women had benign ovarian tumors. Evaluation of the findings of initial ultrasonography revealed that mean size (P=0.008) and proportion of bilateral cysts (P<0.001) were lower in the presence of functional cysts than benign tumors. Additionally, an anechoic pattern was more common among regressed functional cysts than among histologically proven functional cysts (P<0.001). In total, 105 (5.7%) patients required surgery for a functional cyst despite repeat ultrasonography.

CONCLUSION

Repeating ultrasonography prior to surgery may have only a limited ability to prevent unnecessary surgeries for functional cysts.

A preliminary study: The sequential use of the risk malignancy index and contrast-enhanced ultrasonography in differential diagnosis of adnexal masses

The aim of this study was to explore the sequential use of risk malignancy index (RMI) combined with contrast-enhanced ultrasonography (CEUS) in identification diagnosis of adnexal masses.This study contained 2 steps: first, 151 patients were analyzed retrospectively with RMI 1, RMI 2, and RMI 3 indices; receiver operating characteristic (ROC) curves were plotted to analyze area under the curves (AUC), and then RMI cut-off value was obtained according to maximum Youden index (YI, Sensitivity + Specificity - 1) and calculating diagnostic sensitivity, specificity, positive/negative predictive value, and accuracy. Second, 151 cases were divided into 2 groups randomly (105 in study group and 46 in test group); in the study group, the lower cut-off value (LC), upper cut-off value (UC), CEUS cut-off value according to maximum YI, and then these cut-offs were validated in test group.There was no statistical significance in 3 RMI models (P = .35), and RMI1 model was established randomly for following study. When the RMI1 cut-off value was 149, the YI was maximal (0.53), and the sensitivity, specificity, positive/negative predictive value, and accuracy were 71.0%, 81.7%, 77.1%, 75.6%, and 76.2%, respectively. The LC was 15 (sensitivity was 98.0%), the UC was 3000 (specificity was 98.0%), and the CEUS cut-off value was 7 (maximal YI was 0.81). In the test group (46 cases), combining RMI1 LC (15) and UC (3000) with CEUS cut-off value (7), the sensitivity, specificity, positive/negative predictive value, and accuracy were up to 85.7%, 92.0%, 90.0%, 88.5%, and 89.1%, respectively.CEUS can help RMI to make a more effective differential diagnosis of the adnexal mass. Further validation by additional multicenter prospective trials is required.

Can Replacing CA125 with HE4 in Risk of Malignancy Indices 1-4 Improve Diagnostic Performance in the Presurgical Assessment of Adnexal Tumors?

Aims

To assess whether replacing CA125 with HE4 in the classical formulas of risk of malignancy indices (RMIs) can improve diagnostic performance.

Methods

For each of 312 patients with an adnexal mass, classical RMIs 1–4 were computed based on ultrasound score, menopausal status, and serum CA125 levels. Additionally, modified RMIs (mRMIs) 1–4 were recalculated by replacing CA125 with HE4.

Results

Malignant pathology was diagnosed in 52 patients (16.67%). There was no significant difference in diagnostic performance (area under the receiver operating characteristic curve [AUC]) between each classical RMI and its corresponding mRMI. In the entire sample, the AUC was 0.899, 0.900, 0.895, and 0.908 for classical RMIs 1–4 compared to 0.903, 0.929, 0.930, and 0.931 for mRMIs 1–4. In premenopausal patients, the AUC was 0.818, 0.798, 0.795, and 0.802 for classical RMIs 1–4 compared to 0.839, 0.875, 0.876, and 0.856 for mRMIs 1–4. In postmenopausal patients, the AUC was 0.906, 0.895, 0.896, and 0.906 for classical RMIs 1–4 compared to 0.907, 0.923, 0.924, and 0.930 for mRMI 1–4.

Conclusions

Use of HE4 instead of CA125 did not significantly improve diagnostic performance of RMIs 1–4 in patients with an adnexal mass.

Using imaging biomarkers to improve the planning of radical prostatectomies

OBJECTIVES

This exploratory pilot study aimed to evaluate whether adding imaging biomarkers to conventional staging improves complete excision rates after undergoing radical prostatectomy (RP) in the United Kingdom for patients who have not undergone population prostate specific antigen screening. We primarily considered estimates of lesion volume and location based on computer-aided analysis of ultrasound (US) raw radiofrequency (RF) data acquired during trans-rectal ultrasound. The imaging analysis device used had been shown to accurately detect tumor loci within the prostate in previous studies.

METHODS AND MATERIALS

US raw RF data were collected from motorized trans-rectal ultrasound of 68 consecutive men with operable prostate cancer. In this cohort (group 1), locations and volume measurements of lesions suspected of harboring cancer on US raw RF data analysis by prostate HistoScanning, were added to conventional presurgical staging.The unexposed control group comprised 100 men who underwent conventional presurgical staging only (group 2): 50 were operated before and 50 operated after group 1 recruitment. Changes to pre-operative surgical planning and positive lateral margins of RP prostate pathological specimens were the primary outcomes. Data were collected using a Microsoft Excel database and analyzed using Stata.

RESULTS

Baseline demographics were comparable. In group 1, consideration of the additional imaging biomarkers led to changes in 27 (19.9%) operative surgical plans. Absolute rate reduction of a positive surgical margin (PSM) attributable to the imaging-biomarkers was 13.3% (P = 0.029). For stage pT3, PSM rate was reduced from 45.8% (n = 44) to 21.2% (n = 11) (P = 0.0028).

CONCLUSIONS

Obtaining quantitative measurements of preoperative imaging biomarkers appears to improve PSM rates of patients undergoing RP. The greatest PSM rate reduction was observed for pT3 tumors.

Presurgical diagnosis of adnexal tumours using mathematical models and scoring systems: a systematic review and meta-analysis

BACKGROUND Characterizing ovarian pathology is fundamental to optimizing management in both pre- and post-menopausal women. Inappropriate referral to oncology services can lead to unnecessary surgery or overly radical interventions compromising fertility in young women, whilst the consequences of failing to recognize cancer significantly impact on prognosis. By reflecting on recent developments of new diagnostic tests for preoperative identification of malignant disease in women with adnexal masses, we aimed to update a previous systematic review and meta-analysis. METHODS An extended search was performed in MEDLINE (PubMed) and EMBASE (OvidSp) from March 2008 to October 2013. Eligible studies provided information on diagnostic test performance of models, designed to predict ovarian cancer in a preoperative setting, that contained at least two variables. Study selection and extraction of study characteristics, types of bias, and test performance was performed independently by two reviewers. Quality was assessed using a modified version of the QUADAS assessment tool. A bivariate hierarchical random effects model was used to produce summary estimates of sensitivity and specificity with 95% confidence intervals or plot summary ROC curves for all models considered. RESULTS Our extended search identified a total of 1542 new primary articles. In total, 195 studies were eligible for qualitative data synthesis, and 96 validation studies reporting on 19 different prediction models met the predefined criteria for quantitative data synthesis. These models were tested on 26 438 adnexal masses, including 7199 (27%) malignant and 19 239 (73%) benign masses. The Risk of Malignancy Index (RMI) was the most frequently validated model. The logistic regression model LR2 with a risk cut-off of 10% and Simple Rules (SR), both developed by the International Ovarian Tumor Analysis (IOTA) study, performed better than all other included models with a pooled sensitivity and specificity, respectively, of 0.92 [95% CI 0.88-0.95] and 0.83 [95% CI 0.77-0.88] for LR2 and 0.93 [95% CI 0.89-0.95] and 0.81 [95% CI 0.76-0.85] for SR. A meta-analysis of centre-specific results stratified for menopausal status of two multicentre cohorts comparing LR2, SR and RMI-1 (using a cut-off of 200) showed a pooled sensitivity and specificity in premenopausal women for LR2 of 0.85 [95% CI 0.75-0.91] and 0.91 [95% CI 0.83-0.96] compared with 0.93 [95% CI 0.84-0.97] and 0.83 [95% CI 0.73-0.90] for SR and 0.44 [95% CI 0.28-0.62] and 0.95 [95% CI 0.90-0.97] for RMI-1. In post-menopausal women, sensitivity and specificity of LR2, SR and RMI-1 were 0.94 [95% CI 0.89-0.97] and 0.70 [95% CI 0.62-0.77], 0.93 [95% CI 0.88-0.96] and 0.76 [95% CI 0.69-0.82], and 0.79 [95% CI 0.72-0.85] and 0.90 [95% CI 0.84-0.94], respectively. CONCLUSIONS An evidence-based approach to the preoperative characterization of any adnexal mass should incorporate the use of IOTA Simple Rules or the LR2 model, particularly for women of reproductive age.