Head-to-head comparison of [¹⁸F]-FDG and [⁶⁸ Ga]-DOTA-FAPI-04 PET/CT for radiological evaluation of platinum-sensitive recurrent ovarian cancer.

Abstract

Precise radiological evaluation is pivotal for the management of platinum-sensitive recurrent ovarian cancer. We aimed to compare the value of [⁶⁸ Ga]-FAPI and [¹⁸F]-FDG PET/CT for the detection of relapsed lesions. Twenty-nine suspected platinum-sensitive recurrent ovarian cancers were enrolled from January 2022 to July 2022. [¹⁸F]-FDG and [⁶⁸ Ga]-FAPI PET/CT were obtained within 1 week for radiological evaluation. Treatment strategies, visual scores, and Eisenkop scores were recorded. A paired T test was used to compare differences between two scans. Sensitivity, specificity, PPV, NPV, and accuracy were also evaluated. Up to 22 (75.86%) patients displayed inconsistency between two scans. Among them, 4 patients with negative [¹⁸F]-FDG imaging had measurable lesions in [⁶⁸ Ga]-FAPI scans. The treatment strategies were changed in 5 patients (17.24%) due to discrepancies. Finally, 15 (35.7%) patients underwent surgeries, and 14 patients achieved complete resection, except for 1 patient who had milliarc residual disease. TBR, but not SUVmax, of [⁶⁸ Ga]-FAPI was significantly higher than that of [¹⁸F]-FDG in recurrent lesions. Compared with [¹⁸F]-FDG, [⁶⁸ Ga]-FAPI PET presented higher sensitivity and accuracy for lesion detection (96.30% vs. 49.07% and 97.40% vs. 63.87%, respectively). Additionally, [⁶⁸ Ga]-FAPI PET showed a much higher visual score than [¹⁸F]-FDG PET (41 vs. 4), especially for peritoneal metastasis (35 vs. 1). [⁶⁸ Ga]-FAPI PET also presented a larger tumor burden than [¹⁸F]-FDG according to the Eisenkop score (27 vs. 16, p = 0.025). [⁶⁸ Ga]-FAPI was superior to [¹⁸F]-FDG PET/CT for the detection of recurrent lesions, which is pivotal for the individualized management of platinum-sensitive recurrent ovarian cancer.