Skip to main content


Table 1 Benign and malignant ultrasonic features used in simple ultrasound-based rules as proposed by Timmerman et al. [9]

From: Investigating the performance and cost-effectiveness of the simple ultrasound-based rules compared to the risk of malignancy index in the diagnosis of ovarian cancer (SUBSONiC-study): protocol of a prospective multicenter cohort study in the Netherlands

10 Simple ultrasound-based rules
B-features (for predicting a benign tumor)
B1 Unilocular
B2 Presence of solid components, of which largest solid component has largest diameter <7 mm
B3 Presence of acoustic shadows
B4 Smooth multilocular tumor with largest diameter <100 mm
B5 No blood flow (color score 1)
M-features (for predicting a malignant tumor)
M1 Irregular solid tumor
M2 Presence of ascites
M3 At least four papillary structures
M4 Irregular multilocular solid tumor with largest diameter ≥100 mm
M5 Very strong blood flow (color score 4)
  1. Rule 1: If ≥ 1 M-features are present in absence of B-feature(s), the mass is classified as malignant
  2. Rule 2: If ≥ 1 B-features are present in absence of M-feature(s), the mass is classified as benign
  3. Rule 3: If both M-features and B-features are present, or if no B- or M-features are present, the result is inconclusive and a second stage test is recommended