Predicting Complete Cytoreduction with Preoperative [18F]FDG PET/CT in Patients with Ovarian Cancer: A Systematic Review and Meta-Analysis

Abstract

The cornerstone of ovarian cancer treatment is complete surgical cytoreduction. The gold-standard option in the absence of extra-abdominal metastases and intra-abdominal inoperable circumstances is primary cytoreductive surgery (CRS). However, achieving complete cytoreduction is challenging, and only possible in a selected patient population. Preoperative imaging modalities such as [¹⁸F]FDG PET/CT could be useful in patient selection for cytoreductive surgery. In our systematic review and meta-analysis, we aimed to evaluate the role of preoperative [¹⁸F]FDG PET/CT in predicting complete cytoreduction in primary and secondary debulking surgeries. Publications were pooled from two databases (PubMed, Mendeley) with predefined keywords "(ovarian cancer) AND (FDG OR PET) AND (cytoreductive surgery)". The quality of the included studies was assessed with the Prediction model Risk Of Bias Assessment Tool (PROBAST). During statistical analysis, MetaDiSc 1.4 software and the DerSimonian-Laird method (random effects models) were used. Primary and secondary cytoreductive surgeries were evaluated. Pooled sensitivities, specificities, positive predictive values (PPVs), and negative predictive values (NPVs) were calculated and statistically analyzed. Results were presented in forest plot diagrams and summary receiver operating characteristic (SROC) curves. Overall, eight publications were included in our meta-analysis. Four publications presented results of primary, three presented results of secondary cytoreductions, and two presented data related to both primary and secondary surgery. Pooled sensitivities, specificities, and positive and negative predictive values were the following: in the case of primary surgeries: 0.65 (95% CI 0.60-0.71), 0.73 (95% CI 0.66-0.80), 0.82 (95% CI 0.77-0.87), 0.52 (95% CI 0.46-0.59); and in the case of secondary surgeries: 0.91 (95% CI 0.84-0.95), 0.48 (95% CI 0.30-0.67), 0.88 (95% CI 0.81-0.93), 0.56 (95% CI 0.35-0.75), respectively. The PPVs of [¹⁸F]FDG PET/CT proved to be higher in cases of secondary debulking surgeries; therefore, it can be a valuable predictor of complete successful secondary cytoreduction.

Keywords: complete debulking; cytoreductive surgery; ovarian cancer; prediction; preoperative [18F]FDG PET/CT.

Figure 1

Flow diagram of literature search and study selection summary.

Figure 2

Forest plot analyses of sensitivities. Primary (A) and secondary (B) cytoreductive cases are presented separately. Results of the individual studies are represented by the circles. Circle sizes represent the weight of the studies. Pooled sensitivities are shown by the squares. Horizontal lines indicate the confidence intervals [21,22,23,24,25,26,27,28].

Figure 3

Forest plot analyses of specificities. Primary (A) and secondary (B) cytoreductive cases are presented separately. Results of the individual studies are represented by the circles. Circle sizes represent the weight of the studies. Pooled specificities are shown by the squares. Horizontal lines indicate the confidence intervals [21,22,23,24,25,26,27,28].

Figure 4

Forest plot analyses of positive predictive values. Primary (A) and secondary (B) cytoreductive cases are presented separately. Results of the individual studies are represented by the circles. Circle sizes represent the weight of the studies. Pooled PPVs are shown by the squares. Horizontal lines indicate the confidence intervals [21,22,23,24,25,26,27,28].

Figure 5

Forest plot analyses of negative predictive values. Primary (A) and secondary (B) cytoreductive cases are presented separately. Results of the individual studies are represented by the circles. Circle sizes represent the weight of the studies. Pooled NPVs are shown by the squares. Horizontal lines indicate the confidence intervals [21,22,23,24,25,26,27,28].

Figure 6

Summary receiver operating characteristic (SROC) curves. Primary cytoreductive cases (A) are separated from secondary cytoreductive cases (B). Results of the individual studies are represented by the circles. Circle sizes represent the weight of the studies. Q* indicates the point in which the value of sensitivity equals to the value of specificity [21,22,23,24,25,26,27,28].