Comparison of FDG PET/CT with contrast-enhanced CT for the detection of peritoneal carcinomatosis in patients with ovarian cancer

Objectives The aim of this study was to compare FDG-PET/CT with contrast-enhanced CT(CECT) for the detection of peritoneal carcinomatosis from ovarian cancer by using surgical and histopathological findings as the standard of reference.

Methods Forty-nine patients(age range 30-73; mean age 52) with primary(n=33) or recurrent(n=16) ovarian cancer were reviewed for the presence of peritoneal lesions on FDG-PET/CT as well as on contrast-enhanced abdominal CT. The results were compared with the histological findings at laparotomy. Thirty seven patients had peritoneal metastases, while twelve patients had negative histological findings at laparotomy.

Results FDG PET/CT correctly diagnosed 34 in 37 patients with peritoneal metastases and CECT diagnosed 31 in 37 patients. The sensitivity, specificity and accuracy of FDG PET/CT were 91.9%,83.3%, and 89.8% whereas, that of CECT were 86.5%,91.7% and 87.8%, respectively . The positive and negative predictive value of FDG PET/CT were 94.4% and 76.9% and that of CECT were 97.0% and 68.8%. Two false posive PET/CT findings were due to the granulation tissue and the bowel implant with negative histologic finding after chemotherapy. Infrahepatic implant mimicking bowel loop, subphrenic implant, mesenteric and omental metastases caused five false negative CT findings.

Conclusions There is no statistically difference in the diagnostic accuracy of FDG PET/CT and CECT for the detection of peritoneal carcinomatosis from ovarian cancer. There were tendencies for the sensitivity of FDG PET/CT to be superior over CECT, and for the specificity of CECT to be superior over FDG PET/CT.