Debulking surgery for ovarian epithelial cancer performed by a gynaecological oncologist improved survival compared with less specialised surgeons

Current uptake and barriers to wider use of the International Ovarian Tumor Analysis (IOTA) models in Dutch gynaecological practice

OBJECTIVE

Correct referral of women with an ovarian tumor to an oncology department remains challenging. The International Ovarian Tumor Analysis (IOTA) consortium has developed models with higher diagnostic accuracy than the alternative Risk of Malignancy Index (RMI). This study explores the uptake of the IOTA models in Dutch hospitals and factors that impede or promote implementation. Optimal implementation is crucial to improve pre-operative classification of ovarian tumors, which may lead to better patient referral to the appropriate level of care.

STUDY DESIGN

In February 2021, an electronic questionnaire consisting of 37 questions was sent to all 72 hospitals in the Netherlands. One pre-selected gynaecologist per hospital was asked to respond on behalf of the department.

RESULTS

The study had a response rate of 93% (67/72 hospitals). All respondents (100%) were familiar with the IOTA models with 94% using them in practice. The logistic regression 2 (LR2)-model, Simple ultrasound-based rules (SR) and Assessment of Different NEoplasias in the adneXa (ADNEX) model were used in respectively 40%, 67% and 73% of these hospitals. Respondents rated the models overall with an 8.2 (SD 1.8), 8.3 (SD 1.6) and 8.9 (SD 1.3) respectively for LR2, SR and ADNEX on a scale from 1 to 10. Moreover, 89% indicated to have confidence in the results of the IOTA models. The most important factors to improve further implementation are more training (43%), research on sensitivity, specificity and cost-effectiveness in the Dutch health care system (27%), easier usability (24%) and more consultation time (19%).

CONCLUSION

The IOTA ultrasound models are adopted in the majority of Dutch hospitals with the ADNEX model being used the most. While Dutch gynecologists have a strong familiarity and confidence in the models, the uptake varies in reality. Areas that warrant improvement in the Dutch context are more uniformity, education and more research. These findings can be helpful for other countries considering adopting the IOTA models.

IOTA Simple Ultrasound Rules for Triage of Adnexal Mass: Experience from South India

Objective

To assess the diagnostic performance of International Ovarian Tumor Analysis (IOTA) simple ultrasound rules to discriminate adnexal masses as benign or malignant.

Methods

A cross-sectional prospective study was conducted on women scheduled for elective surgery due to adnexal masses. Ultrasound examiner systematically assessed the tumors according to the IOTA simple rules to determine the risk of the tumor being malignant. If the simple rules yielded inconclusive result, pattern recognition was used to categorize the mass. Results were then compared with histologic findings after surgery. Diagnostic performance was assessed by calculating sensitivity and specificity.

Results

Two hundred and five women undergoing surgery were included. The rules were applicable in 183 (89.3%) of the tumors; and for these tumors, sensitivity was 92.8% (95% CI 77-99%) and specificity was 92.9% (95% CI 88-96.4%). Of the tumors, 144 were benign and 39 were malignant. The simple rules yielded inconclusive results in 22 masses which were analyzed by pattern recognition.

Conclusion

IOTA simple rules provide excellent discrimination between benign and malignant adnexal masses.

Improved Detection Rate of Ovarian Cancer Using a 2-Step Triage Model of the Risk of Malignancy Index and Expert Sonography in an Outpatient Screening Setting

OBJECTIVE

Preoperative assessment of adnexal masses with ultrasound has been shown to be time-, cost-effective, and specific. When used in combination with the menopausal status and the tumor marker CA125, the risk of malignancy index (RMI) can be calculated, allowing appropriate preoperative triage of patients to a gynecologist or a gynecological oncologist. Moreover, it allows for accurate planning of the required surgical procedure (laparoscopy vs laparotomy).

METHODS

A large general gynecologic ultrasonic database retrospectively identified 5218 patients for a 14-year period who presented to the outpatient clinic with an adnexal mass. Additional data (menopausal status, histology, CA125 values) were available in 1108 of these patients. Sensitivity, specificity, positive predictive value, and negative predictive value were calculated. The results were then compared with previously published data from a large Australian gynecological cancer center (GCC, n = 204).

RESULTS

With the use of an RMI cutoff of 200, malignant ovarian tumors were correctly triaged to a gynecologic oncologist in 123 of 172 cases, leading to a sensitivity of 72% and specificity of 92% in our general outpatient clinic population compared with a sensitivity of 84% and a specificity of 77% in the GCC high-risk population. The negative predictive value was 95% compared with only 85% in the GCC cohort. We hypothesize that improvement of the overall detection rate of malignancy could be improved from 72% to 85% using a 2-step model, referring patients with an ultrasonic score of 3 to an experienced sonographer who uses pattern recognition.

CONCLUSIONS

The RMI is an easy and reliable tool for the accurate triage of adnexal masses. Its value is higher in an unselected gynecological outpatient setting. Our proposed 2-step model including expert pattern recognition could influence particularly the detection rate in borderline and early-stage ovarian cancers and overcome the limitations of the tumor marker CA125.

The special role of ultrasound for screening, staging and surveillance of malignant ovarian tumors: distinction from other methods of diagnostic imaging

Ovarian cancer is the most aggressive gynecologic malignancy, with a 5-year survival rate ranging around 40%. A crucial factor influencing the prognosis is early detection of a suspicious mass and referral to a gynecologic oncology center for further diagnosis, staging and debulking surgery. Here, we present the different imaging methods ultrasound (US), magnetic resonance imaging, computer tomography (CT) and 18F-fluoro-deoxyglucose positron emission tomography (PET)/CT that are used for the characterization, diagnosis, staging and surveillance of ovarian cancer. In this review, we focus on US and discuss in detail the advantages and the limitations, as well as the appropriate indications for each of the individual imaging techniques.

Multicentre external validation of IOTA prediction models and RMI by operators with varied training

Background:

Correct characterisation of ovarian tumours is critical to optimise patient care. The purpose of this study is to evaluate the diagnostic performance of the International Ovarian Tumour Analysis (IOTA) logistic regression model (LR2), ultrasound Simple Rules (SR), the Risk of Malignancy Index (RMI) and subjective assessment (SA) for preoperative characterisation of adnexal masses, when ultrasonography is performed by examiners with different background training and experience.

Methods:

A 2-year prospective multicentre cross-sectional study. Thirty-five level II ultrasound examiners contributed in three UK hospitals. Transvaginal ultrasonography was performed using a standardised approach. The final outcome was the surgical findings and histological diagnosis. To characterise the adnexal masses, the six-variable prediction model (LR2) with a cutoff of 0.1, the RMI with cutoff of 200, ten SR (five rules for malignancy and five rules for benignity) and SA were applied. The area under the curves (AUCs) for performance of LR2 and RMI were calculated. Diagnostic performance measures for all models assessed were sensitivity, specificity, positive and negative likelihood ratios (LR+ and LR−), and the diagnostic odds ratio (DOR).

Results:

Nine-hundred and sixty-two women with adnexal masses underwent transvaginal ultrasonography, whereas 255 had surgery. Prevalence of malignancy was 29% (49 primary invasive epithelial ovarian cancers, 18 borderline ovarian tumours, and 7 metastatic tumours). The AUCs for LR2 and RMI for all masses were 0.94 (95% confidence interval (CI): 0.89–0.97) and 0.90 (95% CI: 0.83–0.94), respectively. In premenopausal women, LR2−RMI difference was 0.09 (95% CI: 0.03–0.15) compared with −0.02 (95% CI: −0.08 to 0.04) in postmenopausal women. For all masses, the DORs for LR2, RMI, SR+SA (using SA when SR inapplicable), SR+MA (assuming malignancy when SR inapplicable), and SA were 62 (95% CI: 27–142), 43 (95% CI: 19–97), 109 (95% CI: 44–274), 66 (95% CI: 27–158), and 70 (95% CI: 30–163), respectively.

Conclusion:

Overall, the test performance of IOTA prediction models and rules as well as the RMI was maintained in examiners with varying levels of training and experience.

A multicenter prospective external validation of the diagnostic performance of IOTA simple descriptors and rules to characterize ovarian masses

OBJECTIVES

To evaluate the diagnostic performance of the IOTA (International Ovarian Tumor Analysis group) (clinically oriented three-step strategy for preoperative characterization of ovarian masses when ultrasonography is performed by examiners with different background training and experience.

METHODS

A 27-month prospective multicenter cross-sectional study was performed. 36 level II ultrasound examiners contributed in three UK hospitals. Transvaginal ultrasonography was performed using a standardized approach. Step one uses simple descriptors (SD), step two ultrasound simple rules (SR) and step three subjective assessment of ultrasound images (SA) by examiners. The final outcome was findings at surgery and the histological diagnosis of surgically removed masses.

RESULTS

1165 women with adnexal masses underwent transvaginal ultrasonography, 301 had surgery. Prevalence of malignancy was 31% (n=92). SD were able to classify 46% of the masses into benign or malignant (step one), with a sensitivity of 93% and specificity of 97%. Applying SD followed by SR to residual unclassified masses by SD enabled 89% of all masses (n=268) to be classified with a sensitivity 95% of and specificity of 95%. SA was then used to evaluate the rest of the masses. Compared to the risk of malignancy index (RMI), the sensitivity and specificity for the three-step (SD+SR+SA) strategy were 93% (95% CI: 86-97%) and 92% (95% CI: 87-95%) vs. 72% (95% CI: 62-80%) and 95% (95% CI: 91-97%) for RMI, respectively.

CONCLUSION

The IOTA three-step strategy shows good test performance on external validation in the hands of ultrasonography examiners with different background training and experience. This performance is considerably better than the RMI.

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.

Increasing experience in laparoscopic staging of early ovarian cancer

We assessed the effect of increasing experience of a single surgeon (learning curve) in the laparoscopic staging procedure for women with early ovarian cancer and compared the results with the literature. We retrospectively analysed a total of 25 women with apparent early-stage ovarian cancer who underwent a laparoscopic staging procedure by the same surgeon. Three time periods, based on date of surgery, were compared with respect to operating time, amount of lymph nodes harvested and surgical outcome. There was no significant difference in operation time, estimated blood loss and hospital stay between the three periods. There was, however, a significant increase in the median number of pelvic and para-aortal lymph nodes harvested (group1 = 6.5, group 2 = 8.0 and group 3 = 21.0; P < 0.005). For the total period, median operation time was 235 min and median estimated blood loss was 100 ml. The median length of hospital stay was 4.0 days. Two intraoperative and two postoperative complications occurred. The upstaging rate was 32%. The mean interval between initial surgery and laparoscopic staging was 51.2 days. Mean duration of follow-up was 43 months, range (1–116 months). Five (20%) patients had recurrences, and two (8%) patients died of the disease. In conclusion, there is a significant learning curve for the laparoscopic full staging procedure in ovarian cancer. In our study this is mainly reflected in the amount of lymph nodes harvested and not in the total operating time.