The Risk of Malignancy Index (RMI) combines ultrasound score (U), menopausal status (M), and CA-125. An ultrasound shows a multilocular cyst with solid areas bilaterally, with ascites and metastases (U=3, M=3 for postmenopausal, CA-125=180). RMI = U × M × CA-125. The calculated RMI and appropriate management are:
- A RMI = 540; refer to gynecological oncologist
- B RMI = 180; manage conservatively with repeat USS in 3 months
- C RMI = 1620; refer to gynecological oncologist ✓
- D RMI = 540; reassure and discharge
Correct answer: C. RMI = 1620; refer to gynecological oncologist
Explanation
RMI = U × M × CA-125. The ultrasound score U is coded as: U=0 (no features), U=1 (one feature), U=3 (two or more features). This cyst has multilocularity, solid areas, bilaterality, ascites, and metastases — five features, but the U score caps at U=3. Menopausal status M=3 for postmenopausal. RMI = 3 × 3 × 180 = 1620. An RMI >250 indicates high risk of malignancy and mandates referral to a gynaecological oncologist for further management.
Reference: Shaw's Textbook of Gynaecology, 17th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.