Computed tomography adnexal mass score to estimate risk for ovarian cancer

Objective: We wish to develop a CT scan-based scoring system which estimates the probability of adnexal mass malignancy. Methods: Patients (324) undergoing adnexal mass surgery were recruited into the study from June 1, 2002, to January 1, 2009. All study patients had a preoperative CT scan and serum CA-125 test. CT scan abnormalities included any solid tumor components, ascites, and pelvic or abdominal lymphadenopathy and omental caking. Results: There were 225 (70 %) benign and 99 (30 %) malignant ovarian masses. Using logistic regression with the area under the curve of the receiver operating curve of 82 %, the cancer probability was determined by the equation. e^{-3.6372+0.0306*(A) + 0.001*(B) + 0.876*(C) + 1.551 *(D) + 1.7377*(E) + 2.76*(F)}/ 1+ ^{-3.6372+0.0306 *(A) + 0.001*(B) + 0.876*(C) + 1.551*(D) + 1.7377 *(E) + 2.76*(F)} where A = age, B = CA-125, C = solid adnexal mass is 1 and cystic is 0, D = ascites is 1, E = omental caking is 1 and absence is 0, F = node size ≥1 cm is 1 and <1 cm is 0 value. The natural logarithm e is a constant [2.718281828]. For example, for a woman of age 60, CA-125 = 50 U/mL, with solid adnexal mass, ascites, omental caking, and lymphadenopathy, the probability is 0.994. Hence, this woman has a 99.4 % probability of having cancer. Conclusion: The computed tomography adnexal mass score combines CT scan findings, CA-125, and patient age into an equation to predict the malignant probability of an adnexal mass.