Risk of malignancy index 4 in preoperative evaluation of patients with ovarian tumours

Sunita Singhal, Lata Rajoria, Premlata Mital, Alka Batar, Richa Ainani, Monika Agarwal, Urmila ., Kavita Chaudhary


Background: Ovarian tumors usually presents as adnexal masses which may be benign or malignant. Accurate and timely diagnosis of an adnexal mass is a challenge for the gynecologists. Currently clinical examination, ultrasonographic assessment and ovarian tumour markers (CA 125, beta hCG, AFP, LDH) are routinely done at our centre to evaluate patients with ovarian tumours. The study was designed to evaluate the ability of RMI 4 to discriminate benign ovarian tumor from malignant ovarian tumor in patients attending Department of Obstetrics and Gynaecology, S.M.S. Medical College, Jaipur.

Methods: 200 patients diagnosed to have ovarian tumours were included in the study after obtaining written consent. Ultrasonographic characteristic, menopausal status and serum CA 125 levels were documented preoperatively. Risk of malignancy index 4 was calculated and correlated with histopathological diagnosis.

Results: At a cut-off point of 450, RMI 4 had a sensitivity of 67.5% (95% CI: 50.87-81.43%), specificity of 98.75% (95.56-99.85%), positive likelyhood ratio of 54, negative likelyhood ratio of 0.33, a positive predictive value of 93.1%, negative predictive value of 92.4% and diagnostic accuracy of 92.5%.

Conclusions: RMI 4 is a simple, cost effective, reliable scoring system that is easily applicable method in primary evaluation of patients with ovarian tumours with a sensitivity of 67.5% and specificity of 98.75%.


CA 125, Malignancy, Ovarian tumour, Risk of malignancy index, Ultrasonography

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Hartenbach EM, Remington PL. Trends in united states ovarian mortality. 1979-1995.Obstet Gynecol. 1999;93:30-3.

Datasus. Available at

Gillis CR, Hole DJ, Still RM, Davis J, Kaye SB. Medical audit, cancer registration, and survival in ovarian cancer. Lancet. 1991;337:611-2.

Finkler NJ, Benacerraf B, Lavin PT, Wojciechowski C, Knapp RC. Comparison of serum CA-125, clinical impression, and ultrasound in the preoperative evaluation of ovarian masses. Obstet Gynecol. 1988;72:659-64.

Vasilev SA, Schlaerth JB, Campeau J, Morrow CP. Serum CA-125 levels in preoperative evaluation of pelvic masses. Obstet Gynecol. 1988;71:751-6.

Jacob I, Oram D, Fairbanks J, Turner J, Frost C. A risk of malignancy index incorporating CA 125, ultrasound and menopausal status for the accurate pre operative diagnosis of ovarian Cancer. Br J Obstet Gynaecol. 1990;97:922-9.

Tingulstand S, Hagen B, Onsrud M, Kiserud T. Evaluation of Risk of Malignancy Index based on. serum CA125, Ultrasound findings and menopausal status in the preoperative diagnosis of pelvic masses. Br J Obstet Gynecol. 1996;103:826-31.

Tingulstad S, Hagen B, Skjeldestad FE, Halvorsen T, Nustad K, Onsrud M. The risk‐of‐malignancy index to evaluate potential ovarian cancers in local hospitals. Obstetrics Gynecology. 1999 Mar 1;93(3):448-52.

Yamamoto Y, Yamada R, Oguri H, Maeda N, Fukaya T. Comparison of four malignancy risk indices in the preoperative evaluation of patients with pelvic masses. Euro J Obst Gynecol Reprod Biol. 2009 Jun 1;144(2):163-7.

Abdulrahman GO, McKnight L, Singh KL. The risk of malignancy index (RMI) in women with adnexal masses in Wales. Taiwanese J Obst Gynecol. 2014 Sep 1;53(3):376-81.

Mohammed AB, Ahuga VK, Taha M. Validation of the Risk of Malignancy Index in primary evaluation of ovarian masses. Middle East Fertility Society J. 2014 Dec 1;19(4):324-8.

Ashrafgangooei T, Rezaeezadeh M. Risk of malignancy index in preoperative evaluation of pelvic masses. Asian Pac J Cancer Prev. 2011 Jan 1;12(07):1727-30.

Dora SK, Dandapat AB, Pande B, Hota JP. A prospective study to evaluate the risk malignancy index and its diagnostic implication in patients with suspected ovarian mass. J ovarian research. 2017 Dec;10(1):55.

Radhamani S, Akhila MV. Evaluation of adnexal masses-correlation of clinical, sonological and histopathological findings in adnexal masses. Inter J Scientific Study. 2017;4(11):88-92.

Arun-Muthuvel V, Jaya V. Pre-operative evaluation of ovarian tumors by risk of malignancy index, CA125 and ultrasound. Asian Pac J Cancer Prev. 2014 Jan 1;15(6):2929e32.

Aktürk E, Karaca RE, Alanbay İ, Dede M, Karaşahin E, Yenen MC, Başer İ. Comparison of four malignancy risk indices in the detection of malignant ovarian masses. J gynecologic oncology. 2011 Sep 1;22(3):177-82.

Park JW, Park JH, Song ES, Lee BI, Lee JH, Kim KW, et al. Four risk of malignancy indices in evaluation of pelvic masses. Korean J Obst Gynecol. 2012 Sep 1;55(9):636-43.