Relationship between 18F-fluorodeoxyglucose PET/computed tomography metabolic parameters and clinicopathology in endometrial cancer

Abstract

Objective: Endometrial cancer (EC) is the most common invasive gynecological malignancy. This study aimed to retrospectively analyze the relationship between 18F-fluorodeoxyglucose (18F-FDG) PET/computed tomography (CT) parameters and clinicopathological factors in EC patients, and assess whether 18F-FDG PET/CT can be applied for predicting the expressed status of histologic molecular markers.

Methods: Pretreatment clinicopathological characteristics and 18F-FDG PET/CT parameters of maximum standard uptake value (SUVmax), metabolic tumor volume and total lesion glycolysis of primary lesion (MTV-P and TLG-P), and combination of primary lesion and metastases (MTV-C and TLG-C) were retrospectively reviewed in 101 patients with EC.

Results: The median age of these 101 patients was 55 years (range, 35-85 years), and 95 patients (94.1%) presented with abnormal vaginal bleeding, 26 patients (25.7%) with elevated serum cancer antigen 125 (CA-125) and 46 patients (45.5%) with increased human epididymis protein 4 (HE4). Sixty-nine cases were at International Federation of Gynecology and Obstetrics (FIGO) stage I, eight at stage II, 20 at stage III, and four at stage IV. FDG uptake was avid in all cases, and the median SUVmax, MTV-P, TLG-P, MTV-C, and TLG-C were 12.9 (range, 2.8-34.2), 8.1 (range, 0.9-547.8), 52.2 (range, 2.5-4420.6), 8.2 (range, 0.9-790.3), and 58.4 (range, 2.5-6972.2), respectively. Estrogen receptor (ER) and progesterone receptor (PR) positive expressions were in 93.1% (94/101) and 90.1% (91/101) patients, respectively. The median Ki-67 index of 101 cases was 40% (range, 0-95%). P53 pattern was tested in 89 patients and 24 cases were mutant type (27.0%). Mesenchymal-epithelial transition factor (c-Met) expression was investigated in 86 patients, and the positivity was in 36 patients (41.9%). Higher PET/CT metabolic parameters were observed in patients with elevated CA-125 and HE4, advanced FIGO stage and higher Ki-67 index (P < 0.05), but had no association with ER/PR expression, P53 pattern, and c-Met expression (P > 0.05).

Conclusion: FDG uptake in EC was associated with serum CA-125 and HE4, FIGO stage, and Ki-67 index, but no correlations were found between glucose metabolism and ER/PR, P53, and c-Met.