BACKGROUND AND PURPOSE:

• Screening for ovarian cancer in asymptomatic, low risk women is not recommended
• However, research continues on predictive models, particularly how to assess ultrasound images in the presence of an adnexal mass
• The IOTA group, founded in 1999, is a network of approximately 50 multidisciplinary centers, worldwide with aims that include
  • Standardize terminology, definitions and measurements to describe sonographic features of adnexal masses
  • Research that focus on the development of predictive models to estimate the risk of ovarian malignancy when an adnexal mass is present
• Abramowicz et al. (AJOG, 2017) reviewed the performance characteristics of two new ultrasound-based scoring systems
  • Simple Rules
  • Assessment of Different NEoplasias in the adnexa (ADNEX)

METHODS:

• Large patient cohort studies, recruited from multiple participating centers
• Mathematical modeling, based on logistic regression

Simple Rules

• Interpretation
  • B= benign, M= Malignant
  • If ≥1 M features present, absence of B features= tumor is malignant
  • If ≥1 B features present, absence of M features= tumor is benign
  • If both B and M features present = inconclusive
• Benign features
  • Unilocular cyst
  • Solid component <7 mm in diameter
  • Presence of acoustic shadows
  • Smooth multilocular tumor with largest diameter <10cm
  • No detectable color Doppler signal
• Malignant features
  • Irregular solid tumor
  • Ascites
  • ≥4 papillary structures
  • Irregular multilocular mass >10 cm in diameter
  • Strong color Doppler signal

ADNEX:

• A model capable of estimating the risk that an adnexal tumor is benign, borderline, early stage malignant (stage 1), late stage malignant (stage II-IV), or metastatic
• ADNEX model Criteria:
  • Age
  • Serum CA125 (software still calculates risk even if no CA- 125 value is available)
  • Type of center (oncology referral center or general hospital)
  • Maximum diameter of lesion (mm)
  • Proportion of solid tissue (largest solid component diameter divided by maximum lesion diameter)
  • Presence of more than 10 cyst locules (yes/no)
  • Number of intracavitary papillary projections (0,1,2,3,>3)
  • Presence of acoustic shadows (yes/no)
  • Presence of ascites (yes/no)

RESULTS:

• Simple Rules
  • In meta-analysis, sensitivity and specificity were 93% and 81% respectively when inconclusives were considered malignant
  • Negative predictive value is 94.9% if result followed up with expert opinion
  • Model prospectively validated
  • Simple Rules performance was similar even with different levels of ultrasound experience
• ADNEX
  • Results based on clinical and ultrasound data from almost 6000 women
  • Model clinically validated
  • Sensitivity and specificity were 96.5% and 71.3% respectively
  • ROC curve AUC was 0.94
• Simple rules and ADNEX model are validated, good predictive tests for the preoperative classification of adnexal tumors

CONCLUSION:

• Purpose of Simple Rules and ADNEX is to help improve triage and provide more educated decisions regarding management and referral to gyn oncologists in the presence of an adnexal mass
  • Improved outcomes when malignant tumors are managed by gyn oncologists
• ACOG/SGO committee opinion states that
  • Sensitivity and specificity of 86% and 99% respectively for malignancy can be expected when the sonographic evaluation of an adnexal mass includes
    • Tumor size
    • Morphology
    • Wall characteristics
    • Presence of septae
  • Referral to a gyn oncology is recommended when one suspects malignancy
    • Postmenopause: Elevated CA125 or presence of ascites, nodular or fixed pelvic mass or evidence of abdominal or distant metastasis
    • Premenopause: Very elevated CA125, ascites or evidence of abdominal or distant metastasis
  • The authors conclude that Simple Rules or ADNEX would yield better results in discriminating benign from malignant adnexal masses
  • Models are simple but not yet used in the US
    • Litigation concerns result in active management of adnexal masses
    • Simple Rules and ADNEX are not yet validated in the USA
  • The study suggests the models should be validated in the US and introduced into medical practice

Learn More – Primary Sources:

Ovarian mass-differentiating benign from malignant. The value of the International Ovarian Tumor Analysis (IOTA) ultrasound rules

Simple Rules model available at: http://www.iotagroup.org/simplerules/

ADNEX software available at: http://www.iotagroup.org/adnexmodel/site%20iota.html

Related ObG Topics:

Evaluation of the Adnexal Mass

Screening for Ovarian Cancer – Fantasy or Reality?

Obstetrics Critical Care Course

USPSTF Releases Final Recommendation On Ovarian Cancer Screening

BRCA1 & BRCA2 Mutations: What Are the Risks for Developing Breast and Ovarian Cancer?