A 55-year-old woman has a complex adnexal mass with CA-125 of 320 U/mL. The IOTA (International Ovarian Tumor Analysis) 'simple rules' classify a mass as likely malignant if there are features of malignancy (M-features) WITHOUT features of benignity (B-features). Which of the following is an M-feature in the IOTA simple rules?
- A Smooth multilocular cyst <100 mm
- B Irregular solid tumor with ascites ✓
- C Presence of acoustic shadows
- D Bilateral simple cyst
Correct answer: B. Irregular solid tumor with ascites
Explanation
IOTA simple rules classify adnexal masses using 5 B-features (benign: unilocular cyst, solid components <7mm, acoustic shadows, smooth multilocular <100mm, no blood flow) and 5 M-features (malignant: irregular solid tumor, ascites, ≥4 papillary projections, irregular multilocular solid >100mm, very strong blood flow). An irregular solid tumor with ascites is a classical M-feature. Acoustic shadows and smooth multilocular cysts are B-features. Bilateral simple cysts are not classified under these rules.
Reference: Shaw's Textbook of Gynaecology, 17th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.