Clinical impact of pre-treatment FDG-PET/CT staging of primary ovarian, fallopian tube, and peritoneal cancers in women

Introduction: To assess the clinical impact of preoperative fludeoxyglucose (FDG) with positron emission tomography (PET) and computed tomography (CT) in women with ovarian, fallopian tube, or peritoneal cancer with focus on consequences of added findings (AFs).

Material and methods: FDG-PET/CT was implemented as a standard imaging modality for women with newly diagnosed ovarian, fallopian tube, or peritoneal cancer at our institution in 2008. After full implementation, all preoperative scans were reviewed and AFs were evaluated from January 2011 to December 2012. Decisions regarding further examination made at the first multidisciplinary team conference were recorded. Subsequent procedures were tracked via medical records, and the impact of AFs on additional examinations, delay, and change in treatment plans was evaluated.

Results: Forty-four (21.1%) of 209 women presented with AFs. Further examination was performed in 35/44 (79.5%). Malignancy was identified in 15/35 (42.9%), revealing metastases from ovarian, fallopian tube, or peritoneal cancer in 11, a synchronous primary cancer in 3, and recurrence of a previous cancer in 1 woman. The ovarian, fallopian tube, or peritoneal cancer metastases were localized in the lungs, uterus, colon, vagina, and breasts. The remaining 20 AFs revealed 2 benign lesions and 1 pre-malignant lesion, whereas no abnormality was found in 17. Further examination of AFs resulted in a significant time delay until treatment start of median 4 days (range 1-83 days, P < 0.004).

Conclusions: Further examinations of AFs by FDG-PET/CT delayed time to start of treatment by median 4 days in women with newly diagnosed ovarian, fallopian tube, or peritoneal cancer in a contemporary institution with fast-track access to additional diagnostics. The clinical implications of this must be balanced against the gain of detecting unrecognized malignancy in 15 of 209 women (7.2%).