Utility of [18F]FDG- PET/CT in Initial Staging and Management of Patients with Esophageal Carcinoma: A Tertiary Care Center Experience.

Abstract

Aim of the study: This study aims to study the utility of 18F-fluorodeoxyglucose positron emission tomography/computed tomography (¹⁸F-FDG PET/CT) findings in the initial staging and management of patients with esophageal carcinoma.

Materials and methods: In this prospective study, we evaluated 74 patients with a mean age of 59.4 ± 11.6 with a range of 35-86 years. Comparison between the mean and standard deviation of SUV_max of primary tumor between two histopathological groups, squamous cell carcinoma (SCC) and adenocarcinoma (AC) was done using unpaired Student's t-test. The mean of SUV_max of primary tumor in relation to localized tumor to nodal to distant metastases was assessed by ANOVA test. P <0.05 was considered statistically significant. The extent of agreement between findings of contrast-enhanced computed tomography (CECT) chest and abdomen and ¹⁸F-FDG PET/CT was done using Cohen's kappa coefficient (κ).

Results: Among total n = 74 (42 males and 32 females with mean age 59.4 ± 11.4; range 35-86 years) patients, SCC was seen in 78.4% and AC in 21.6% of patients. There is a progressively increased SUV_max value of primary tumor with nodal and distant metastases. ¹⁸F-FDG PET/CT showed disease of Stage I-II in 12.1%, Stage III in 20.2%, Stage IVA in 25.6%, and Stage IVB in 41.8% patients. There is agreement between ¹⁸F-FDG PET/CT and CECT chest and abdomen in the evaluation of regional lymph nodes (37.8% vs. 36.4%; κ - 0.96), nonregional lymph nodes (24.3% vs. 20.2%; κ -0.74), and distant organ involvement (21.6% vs. 17.5%; κ -0.82). In addition, ¹⁸F-FDG PET/CT found synchronous malignancies in 4.0% of patients.

Conclusion: ¹⁸F-FDG PET/CT metabolic parameters help in identifying metastatic involvement in morphologically equivocal and clinically suspicious lesions in carcinoma esophagus patients. Being a whole-body imaging modality, ¹⁸F-FDG PET/CT has inbuilt advantage to detect occult, distant metastases, and synchronous malignancies for effective staging and improving plan of clinical management.