Objective:To investigate the uptake patterns of 18F-fluorodeoxy glucose ( 18F-FDG) in the endometrium using positron emission tomography (PET) imaging and to differentiate these from stage IA endometrial cancer. Methods:From September 2022 to April 2024, a prospective inclusion of 354 women without gynecological diseases and no hormone usage who underwent 18F-FDG PET-CT examinations at the affiliated hospital of Qingdao University were set as the physiological group, while a group containing 42 cases of Stage IA endometrial carcinoma was also set. The physiological group was divided into five groups based on the menstrual cycle: menstrual period, proliferative phase, ovulatory phase, secretory phase, and menopausal phase. The images were analyzed using visual and quantitative measurements; quantitative analysis indicators were standardized uptake value maximum (SUVmax) and the region of interest/liver ratio (R/L value). Receiver operating characteristic (ROCs) curve was used to determine the optimal cutoff values for SUVmax and R/L value. A clinical model was established using binary logistic regression, and ROC curves were drawn to evaluate the predictive performance of the model. Results:The uptake of 18F-FDG in the endometrium exhibited cyclical variations throughout different physiological phases, with higher uptakes observed during the menstrual and ovulation phases (SUVmax values of 6.66±3.26 and 3.89±1.21, respectively), which are significantly higher than those in the proliferative phase [median SUVmax of 2.54 (2.02, 3.47)], secretory phase (SUVmax of 2.55±0.86), and menopausal phase [SUVmax median of 2.04 (1.69, 2.29)]. During the menstrual and ovulation phases, the radiotracer accumulation patterns were triangular in 105 cases, oval in 32 cases, and round-like in 2 cases. All 42 cases of endometrial cancer showed 18F-FDG uptake, with radiotracer accumulation patterns being round-like in 17 cases, oval in 10 cases, triangular in 9 cases, and irregular in 6 cases. There were statistically significant differences in the shapes of radiotracer concentration between the menstrual, ovulatory periods, and endometrial carcinoma (both P＜0.001). The SUVmax and R/L values in menstrual period and ovulatory period were significantly lower than that in endometrial carcinoma group ( P＜0.001). During the menstrual phase, the optimal cutoff values for SUVmax and R/L in distinguishing between endometrial and endometrial cancer were 12.59 and 3.81, respectively, with corresponding AUCs of 0.885 and 0.842. After incorporating endometrial uptake morphology into the model, the AUCs was improved to 0.969 and 0.948, respectively. During the ovulatory phase, the optimal cutoff values for SUVmax and R/L were 5.96 and 2.85, respectively, with AUCs of 0.984 and 0.968. After integrating endometrial uptake morphology into the model, the AUCs were increased to 0.999 and 0.998, respectively. Conclusions:The 18F-FDG PET imaging of the endometrium shows higher uptake during the menstrual and ovulatory periods, primarily triangular in shape; endometrial carcinoma uptake is significantly higher than the physiological uptake during the menstrual and ovulatory periods, mainly in circular, oval, and irregular shapes. When SUVmax≥5.96, R/L≥2.85, combined with the physiological cycle of the subjects and the morphological characteristics of the radiotracer concentration, it is possible to effectively differentiate between physiological uptake and Stage IA endometrial carcinoma.

Objective:To investigate the uptake patterns of 18F-fluorodeoxy glucose ( 18F-FDG) in the endometrium using positron emission tomography (PET) imaging and to differentiate these from stage IA endometrial cancer. Methods:From September 2022 to April 2024, a prospective inclusion of 354 women without gynecological diseases and no hormone usage who underwent 18F-FDG PET-CT examinations at the affiliated hospital of Qingdao University were set as the physiological group, while a group containing 42 cases of Stage IA endometrial carcinoma was also set. The physiological group was divided into five groups based on the menstrual cycle: menstrual period, proliferative phase, ovulatory phase, secretory phase, and menopausal phase. The images were analyzed using visual and quantitative measurements; quantitative analysis indicators were standardized uptake value maximum (SUVmax) and the region of interest/liver ratio (R/L value). Receiver operating characteristic (ROCs) curve was used to determine the optimal cutoff values for SUVmax and R/L value. A clinical model was established using binary logistic regression, and ROC curves were drawn to evaluate the predictive performance of the model. Results:The uptake of 18F-FDG in the endometrium exhibited cyclical variations throughout different physiological phases, with higher uptakes observed during the menstrual and ovulation phases (SUVmax values of 6.66±3.26 and 3.89±1.21, respectively), which are significantly higher than those in the proliferative phase [median SUVmax of 2.54 (2.02, 3.47)], secretory phase (SUVmax of 2.55±0.86), and menopausal phase [SUVmax median of 2.04 (1.69, 2.29)]. During the menstrual and ovulation phases, the radiotracer accumulation patterns were triangular in 105 cases, oval in 32 cases, and round-like in 2 cases. All 42 cases of endometrial cancer showed 18F-FDG uptake, with radiotracer accumulation patterns being round-like in 17 cases, oval in 10 cases, triangular in 9 cases, and irregular in 6 cases. There were statistically significant differences in the shapes of radiotracer concentration between the menstrual, ovulatory periods, and endometrial carcinoma (both P＜0.001). The SUVmax and R/L values in menstrual period and ovulatory period were significantly lower than that in endometrial carcinoma group ( P＜0.001). During the menstrual phase, the optimal cutoff values for SUVmax and R/L in distinguishing between endometrial and endometrial cancer were 12.59 and 3.81, respectively, with corresponding AUCs of 0.885 and 0.842. After incorporating endometrial uptake morphology into the model, the AUCs was improved to 0.969 and 0.948, respectively. During the ovulatory phase, the optimal cutoff values for SUVmax and R/L were 5.96 and 2.85, respectively, with AUCs of 0.984 and 0.968. After integrating endometrial uptake morphology into the model, the AUCs were increased to 0.999 and 0.998, respectively. Conclusions:The 18F-FDG PET imaging of the endometrium shows higher uptake during the menstrual and ovulatory periods, primarily triangular in shape; endometrial carcinoma uptake is significantly higher than the physiological uptake during the menstrual and ovulatory periods, mainly in circular, oval, and irregular shapes. When SUVmax≥5.96, R/L≥2.85, combined with the physiological cycle of the subjects and the morphological characteristics of the radiotracer concentration, it is possible to effectively differentiate between physiological uptake and Stage IA endometrial carcinoma.

Abstract: Objective To analyze the epidemiological characteristics of viral hepatitis E in Fujian Province from 2012-2021, and to provide scientific evidence for the prevention and control of hepatitis E in the future. Methods Descriptive epidemiological method was used to analyze hepatitis E cases in Fujian Province from 2012 to 2021. Results From 2012 to 2021, a total of 8 877 cases of hepatitis E were reported in Fujian Province from 2012-2021. The overall incidence rate showed a decreasing trend (χ2trend =458.14, P<0.001), with the lowest incidence rate of 1.32/100 000 in 2020 and an annual average incidence rate of 2.29/100 000 per year. The incidence was higher in winter and spring, with the months of March and April having the highest number of reported cases (2 146, 24.17%) and the fewest cases were reported in September (571, 6.43%). The difference in reported incidence rates between cities was statistically significant (χ2=1 877.75, P<0.01). The comprehensive experimental zone of Pingtan had the highest average reported incidence rate of 6.03/100 000, while Zhangzhou had the lowest at 0.94/100 000. The number of male cases was higher than the number of female cases, with a male to female ratio of 2.04∶1. The disease was most prevalent among middle-aged and elderly individuals, with the age group of 40-<65 years having the highest number of reported cases, accounting for 57.44% (5 099/8 877) of all cases. The age group of 50-<55 years had the highest reported incidence, with the number of reported cases increasing with age below 50 years, but decreasing with age over 50 years. As for occupational distribution, peasants had the highest proportion of the disease, accounting for 34.49% (3 062 cases) of the total cases. Conclusions The reported incidence rate of hepatitis E in Fujian showed a downward from 2012 to 2021. Due to the impact of COVID-19, incidence of the lowest was 2020, but it did not reflect the true situation of the disease, which may have affected trend of hepatitis E. In order to control and reduce the incidence of hepatitis E, efforts should be made to increase publicity and education on health knowledge and vaccination among key areas and populations, strengthen monitoring and diagnostic capability, and implement comprehensive prevention and control measures.