Preoperative detection of ovarian cancer by color doppler ultrasonography and CA 125

Abstract

Purpose: Early detection of ovarian malignancy is of great clinical importance. The high mortality rate is due to the difficulties with the early detection of ovarian cancer. Current research attempted to assess the accuracy of Color Doppler Sonography and serum CA-125 level as diagnostic tool of ovarian tumor.

Materials and Methods: In this cross-sectional study, 60 consecutive patients with ovarian tumor attending the Department of Obstetrics and Gynecology of BSMMU were recruited. Of the study participants 23.3% belong to 16-25 year age group, 20% belong to 26-35 years age group and 23.30% each were of 46-55 years and > 55 years age group. All the patients recruited were from in-patient department and had undergone surgery. Following excision, routine histopathology revealed 43.30% malignant (n=26) and 56.7% (n=34) benign ovarian lesion. Data were collected from the clinical history form and bimanual pelvic examination, serum CA 125 levels, estimation of Resistance index (RI), Pulsatility Index (PI), Novel Index by CDS and post-operative histo-pathological findings were then recorded. Sensitivity, specificity, accuracy, positive and negative predictive value of the diagnosis made by CDS, CA125, in the discrimination of the benign and malignant ovarian tumors was calculated. Using Receiver operative characteristics analysis the accuracy of RI, PI, CA 125 and Novel Index in the diagnosis of ovarian tumor (benign or malignant) were assessed.

Results: With the Cut-off of <.5, Resistance Index is found to be capable of detecting 92% of malignant cases (sensitivity 91.7), and could detect 89% (specificity 88.9) of benign cases correctly which translates in to 90% accuracy in the diagnosis of ovarian tumor. Predictive values for positive (84.6) and negative (94.1) tests were also found to be quite high. Pulsatility index was found to be moderate accuracy (63.3%) with cutoff <1 for malignancy, however low predictive value for a positive test (38.5) questions its use. Both CA-125 and Novel Index showed similar level of sensitivity and specificity. Although Novel Index is derivative of CA125, Novel Index demonstrated better diagnostic accuracy and negative predictive value. The cutoff for CA 125 was mandated as 83.58. With the value the sensitivity is 76.9% and the specificity is 94.1%. RI is found to be more sensitive in detection of positive cases (Malignant) and CA125 is found to be more accurate in detection of negative cases (Benign). However a combination could be tried to make a better detection.

Conclusion: Color Doppler ultra-sonography and CA125 excels in different tasks, the study concludes in favor of concurrent use of the methods for improving efficacy and thus early detection of ovarian malignancy.

DOI: 10.3329/bmrcb.v36i2.6991

Bangladesh Med Res Counc Bull 2010; 36: 68-73