Clinical utility of positron emission tomography/computed tomography in the evaluation of suspected recurrent ovarian cancer in the setting of normal CA-125 levels.
OBJECTIVE
This study was conducted to estimate the accuracy of [18F]-fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) as compared with contrast-enhanced CT (CECT) in detecting cancer in patients who have normal cancer antigen (CA)-125 (<35 U/dL) but are suspected of having a recurrent disease based on clinical symptoms.


METHODS
We retrospectively reviewed the records of patients who had undergone primary cytoreductive surgery and subsequently underwent CECT and FDG-PET/CT for suspected recurrence. [18F]-fluorodeoxyglucose positron emission tomography/computed tomography and CECT interpretation to evaluate a recurrent disease was carried out independently by 2 experienced radiologists who were blinded to the final diagnosis for the suspected recurrence. Long-term follow-up imaging (12 months) and biopsy reports were used to assess the true status of the suspected recurrence seen on FDG-PET/CT or CECT. Sensitivity and specificity of all modalities were estimated. McNemar test was used to compare pairs of modalities. All tests were 2-sided, and P < or = 0.05 was considered statistically significant.


RESULTS
Sixty-six patients met the eligibility criteria for inclusion in our analysis. Fifty-eight percent (18/31) and 54% (17/31) of the patients with normal CA-125 levels had evidence of a recurrent disease on FDG-PET/CT and CECT, respectively. Thirty-one percent (6/19) of the patients with no indication of cancer on CECT had evidence of disease on FDG-PET/CT images, which was supported by pathological proof.


CONCLUSIONS
[18F]-Fluorodeoxyglucose positron emission tomography/computed tomography is capable of detecting ovarian cancer recurrence in symptomatic patients with normal CA-125 levels and, in this setting, has slightly better sensitivity than CECT and can be considered as the frontline modality for all such patients.
Bhosale
Priya
P
Department of Diagnostic Radiology, The University of Texas M. D. Anderson Cancer Center, Houston, TX 77030, USA. Priya.bhosale@di.mdacc.tmc.edu
Peungjesada
Silanath
S
Wei
Wei
W
Levenback
Charles F
CF
Schmeler
Kathleen
K
Rohren
Eric
E
Macapinlac
Homer A
HA
Iyer
Revathy B
RB
D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D014408:Biomarkers, Tumor / Q000097:blood*; D018394:CA-125 Antigen / Q000097:blood*; D015331:Cohort Studies; D005260:Female; D019788:Fluorodeoxyglucose F18; D006801:Humans; D008875:Middle Aged; D009364:Neoplasm Recurrence, Local / Q000097:blood / Q000000981:diagnostic imaging*; D010051:Ovarian Neoplasms / Q000097:blood* / Q000000981:diagnostic imaging* / Q000473:pathology / Q000628:therapy; D049268:Positron-Emission Tomography / Q000379:methods; D011237:Predictive Value of Tests; D019275:Radiopharmaceuticals; D012016:Reference Values; D012189:Retrospective Studies; D012680:Sensitivity and Specificity; D014057:Tomography, X-Ray Computed / Q000379:methods
D014408:Biomarkers, Tumor; D018394:CA-125 Antigen; D019275:Radiopharmaceuticals; D019788:Fluorodeoxyglucose F18