Role of [18F]FDG PET/CT in the assessment of suspected recurrent ovarian cancer: correlation with clinical or histological findings.

PURPOSE: To evaluate the accuracy of integrated positron emission tomography (PET) and computed tomography (CT) for depiction of suspected recurrent ovarian carcinoma after treatment, with use of clinical or histological findings as the reference standard.

METHODS: Seventy-seven women (median age, 51 years) with ovarian carcinoma treated with primary cytoreductive surgery followed by platinum-based combination chemotherapy were included, and [18F]fluorodeoxyglucose (FDG) PET/CT was performed for suspected recurrence. In all patients, imaging findings were compared with results of histological examination after surgical exploration or clinical follow-up to determine the diagnostic accuracy of PET/CT in the evaluation of disease status. Fisher's exact test was used to measure the ability of PET/CT to predict recurrent lesions.

RESULTS: Forty-five (58.4%) of the 77 patients had documented recurrence during surgical exploration or clinical follow-up, while 32 (41.6%) had no evidence of recurrent tumour. Of the 45 patients with recurrent disease, 27 (60%) were confirmed to have recurrence by surgical biopsy. A correlation was found between PET/CT and histological or clinical analyses (kappa = 0.894). The overall sensitivity, specificity, accuracy, positive predictive value and negative predictive value of PET/CT were 93.3%, 96.9%, 94.8%, 97.7% and 91.2%, respectively. PET/CT modified the diagnostic or treatment plan in 19 (24.7%) patients, by leading to the use of previously unplanned therapeutic procedures in 11 (57.9%) patients and the avoidance of previously planned diagnostic procedures in eight (42.1%) patients.

CONCLUSION: Integrated FDG PET/CT is a sensitive post-therapy surveillance modality for the detection of recurrent ovarian cancer; it aids decisions on treatment plans and may ultimately have a favourable impact on prognosis.