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. $$ frac{{{text{e}}^{{ - 3. 6 3 7 2 { } + , 0.0 30 6 { }* , left( {text{A}} right) , + , 0.00 1 { }* , left( {text{B}} right) , + , 0.{ 876 }* , left( {text{C}} right) + 1. 5 5 1 { }* , left( {text{D}} right) , + { 1}. 7 3 7 7 { }* , left( {text{E}} right) , + { 2}. 7 6 { }* , left( {text{F}} right)}} }}{{ 1+ {text{e}}^{{ - 3. 6 3 7 2 { } + , 0.0 30 6 { }* , left( {text{A}} right) , + , 0.00 1 { }* , left( {text{B}} right) , + , 0. 8 7 6 { }* , left( {text{C}} right) , + { 1}. 5 5 1 { }* , left( {text{D}} right) , + { 1}. 7 3 7 7 { }* , left( {text{E}} right) , + { 2}. 7 6 { }* , left( {text{F}} right)}} }} $$ 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.