CA 125, PET alone, PET-CT, CT and MRI in diagnosing recurrent ovarian carcinoma: a systematic review and meta-analysis.

BACKGROUND AND
PURPOSE: Ovarian cancer is the commonest tumor in female patients with a propensity for recurrence even after primary chemotherapy in early stage. The accuracy of CA 125, PET alone, PET-CT, CT and MRI in diagnosing the recurrent ovarian carcinoma has never been systematically assessed, and present systematic review was aimed at this issue.
METHODS: We searched for articles published from January 1995 to November 2007, inclusion criteria including: articles were reported in English or Chinese; CA 125, PET whether interpreted with or without the use of CT, CT or MRI was used to detect recurrent ovarian carcinoma; Histopathologic analysis and/or close clinical and imaging follow-up for at least 6 months. We extracted data to calculate sensitivity, specificity, SROC curves and AUC and to test for heterogeneity. RESULT: In 34 included studies, CA 125 had the highest pooled specificity, 0.93 (95% CI: 0.89-0.95); PET-CT had highest pooled sensitivity, 0.91 (95% CI: 0.88-0.94). The AUC of CA 125, PET alone, PET-CT, CT and MRI were 0.9219, 0.9297, 0.9555, 0.8845 and 0.7955, respectively. Results of pairwise comparison between each modality demonstrated AUC of PET, whether interpreted with or without the use of CT, was higher than that of CT or MR, p<0.05. The pooled sensitivity, pooled specificity and AUC showed no statistical significance between PET alone and PET-CT. There was heterogeneity among studies and evidence of publication bias.
CONCLUSION: PET-CT might be a useful supplement to current surveillance techniques, particularly for those patients with an increasing CA 125 level and negative CT or MR imaging. However, regarding to diagnostic accuracy, interpreted CT images may have limited additional value on PET in detecting recurrent ovarian cancer.