Introduction
Cervical cancer is a common gynecological malignancy with around 569,847
new cases and 311,365 deaths annually worldwide, and a significant
proportion of patients are diagnosed at a locally advanced
stage.1 For locally advanced cervical cancer (LACC),
concurrent chemoradiotherapy (CCRT), using cisplatin-based chemotherapy
in association with pelvic external-beam radiotherapy and subsequent
brachytherapy is considered the standard treatment.2Although the contribution of CCRT toward an improvement in survival
outcomes and reduction in recurrence has been well confirmed, the
complete clinical response of these patients is 70%–90%, and about
one-third of patients with CC experience recurrence.3,
4
Accurate prediction of recurrence is of great significance. Several
traditional clinical and pathological factors are identified as poor
prognostic factors, which include advanced International Federation of
Gynecology and Obstetrics (FIGO) stage, presence of lymph node
metastasis, parametrial invasion, histological tumor type, and a large
tumor diameter.5-7 However, there are still no
satisfactory parameters sufficient to predict prognosis accurately.
Computed tomography (CT), magnetic resonance imaging (MRI), and
fluorodeoxyglucose positron emission CT (FDG PET/CT) are the most
commonly used imaging modalities. Compared to CT or MRI, FDG PET/CT
could show metabolic information on tumors and more accurate assessment
of lymph node involvement, distant metastasis, and recurrent
disease.8 Therefore, FDG PET/CT has been widely used
in staging, therapeutic strategy, and treatment response assessment of
patients with CC.9
With the technology developed, imaging has provided the potential of a
prognostic biomarker.10 Except for the aforementioned
roles, quantitative parameters derived from FDG-PET/CT, including
maximum standardized uptake value (SUVmax), average SUV
(SUVmean), metabolic tumor volume (MTV), and total
lesion glycolysis (TLG), have recently been proposed as prognostic
biomarkers for patients with LACC who are treated with CCRT, but the
results of studies show some extent differences. For example, Im et al.
detected that the patients with high SUVmax measurement
on tumor tissue had a higher risk of recurrence or progression than
those with low SUVmax (HR= 2.14, 95%CI=1.08-4.22,
P=0.029) ,11 but Chong et al. draw the opposite
conclusion (HR=0.673, 95%CI=0.5-4.0, P=0.412) .12Therefore, we performed this meta-analysis to synthetize the relevance
of FDG PET/CT parameters as prognostic biomarkers for patients with LACC
who are treated with CCRT.