To investigate the ¹⁸F-fluorodeoxyglucose (FDG) PET/CT imaging features of appendiceal mucinous neoplasms (AMN) and the diagnostic value of PET/CT for AMN.

Sixteen patients (5 males, 11 females, age: (59.6±12.2) years) with AMN who underwent ¹⁸F-FDG PET/CT examination in the First Affiliated Hospital of Dalian Medical University between April 2013 and May 2019 were retrospectively analyzed. All AMN were divided into low-grade AMN (LAMN) group and mucinous appendiceal adenocarcinoma (MAA) group according to pathological results. The PET/CT imaging features were analyzed and compared between LAMN group and MAA group. The PET/CT imaging results were compared with histopathological results. Independent-sample t test was used for data analysis.

On PET/CT images, LAMN group showed shorter diameter ((3.31±0.74) vs (3.71±1.52) cm; t=-0.667, P<0.05) and lower cystic wall metabolic level (maximum standardized uptake value (SUV_max): 2.73±1.31 vs 6.70±5.95; t=-1.844, P<0.05) than those of MAA group. AMN usually showed slightly high density fluid ((23.88±13.14) HU) in the appendiceal region, punctate calcification (10/16) and low to moderate metabolism of the cystic wall (SUV_max: 4.71±4.64), and the pseudomyxoma peritonei incidence rate of AMN was about 7/16. Compared with the pathological results, PET/CT accurately diagnosed 11 cases of AMN, including 3 cases of AMN with pseudomyxoma peritonei, the sensitivity was 11/16, 3/7, respectively. PET/CT accurately diagnosed 7/9 patients with metastasis.

¹⁸F-FDG PET/CT examination has good diagnostic value for AMN.

Appendiceal neoplasms; Adenocarcinoma, mucinous; Positron-emission tomography; Tomography, X-ray computed; Deoxyglucose