Correlation of ¹⁸F-FDG PET/CT metabolic parameter, inflammatory indexes and SCC-Ag with clinical staging and pathological features of locally progressive cervical squamous carcinoma

Objective To investigate the correlation of ¹⁸F-fluorodeoxyglucose (FDG) PET/CT metabolic parameters, inflammatory indexes, and squamous cell carcinoma antigen (SCC-Ag) with the International Federation of Obstetrics and Gynecology (FIGO) clinical stage and pathological characteristics in locally advanced cervical squamous carcinoma and provide a reference for the evaluation of pathological features and accurate clinical staging of cervical squamous carcinoma.

Methods The clinical data of 56 patients with cervical squamous carcinoma who were aged (56.0±9.3) years and treated in Qingdao Central Hospital from August 2015 to October 2023 were retrospectively analyzed. All patients were diagnosed as having cervical squamous carcinoma (Stage ⅡB−ⅣA) on the basis of histopathological findings and underwent ¹⁸F-FDG PET/CT and serological examination before treatment to obtain the maximum standardized uptake value (SUV_max), mean standardized uptake value (SUV_mean), metabolic tumor volume (MTV), total lesion glycolysis (TLG), lymph node SUV_max (nSUV_max), SCC-Ag, and inflammatory indexes. Spearman rank correlation analysis was used to analyze the correlation among ¹⁸F-FDG PET/CT metabolic parameters, serum tumor markers, inflammatory indexes, and clinicopathological features of ⅡB−ⅣA cervical squamous carcinoma.

Results Of the 56 patients, 13(23.21%) were at stage ⅡB, 34(60.71%) were at stage Ⅲ, and 9(16.07%) were at stage ⅣA. Thirty-eight (67.86%) of the patients had lymph node metastasis at the initial stage. Some ¹⁸F-FDG PET/CT metabolic parameters, such as nSUV_max, MTV, TLG, tumor-to-liver ratio SUV_max, and node-to-liver ratio SUV_max, were positively correlated with FIGO staging (r=0.317–0.571, all P<0.05), and inflammation indicators neutrophil-to-lymphocyte ratio and platelet-to-lymphocyte ratio were positively correlated with FIGO staging (r=0.311, 0.285; both P<0.05). Meanwhile, lymphocyte-to-monocyte ratio and albumin (ALB) were negatively correlated with FIGO staging (r=−0.481, −0.547; both P<0.05). All of the ¹⁸F-FDG PET/CT metabolic parameters were positively correlated with lymph node metastasis (r=0.300–0.823, all P<0.05), and ALB was negatively correlated with lymph node metastasis (r=−0.303, P<0.05). SCC-Ag was positively correlated with FIGO stage and lymph node metastasis in cervical squamous carcinoma (r=0.515, 0.433; both P<0.05). ¹⁸F-FDG PET/CT metabolic parameters, inflammatory indexes, and SCC-Ag were not statistically significant correlated with pathologic grade (r: from –0.083 to 0.141, all P>0.05).

Conclusions The ¹⁸F-FDG PET/CT metabolic parameters of the primary foci of cervical squamous carcinoma, inflammatory indexes, and serum tumor markers have different degrees of correlation with clinicopathological features and FIGO grading and can reflect the biological and pathological characteristics of tumors in patients with cervical squamous carcinoma. They are conducive to the evaluation of pathological features and accurate clinical staging of cervical squamous carcinoma.