ABSTRACT
Objective: to investigate the clinical value of 18F-FDG PET-CT in the diagnosis of malignant tumor when serum carcinoembryonic antigen [CEA] level is elevated for unknown primary lesion
Study Design: a descriptive study
Place and Duration of Study: department of Nuclear Medicine, Luoyang Central Hospital Affiliated to Zhengzhou University, Henan, China, from March 2015 to March 2017
Methodology: a total of 120 cases of parallel 18F-FDG PET-CT examination with serum CEA level of patients with unexplained source examined were chosen. Those with a known disease or with incomplete record of clinical and/or relevant laboratory examinations were excluded. Pathological examination, results of clinical follow-up and other imaging tests constituted the clinical value of 18F-FDG PET-CT in the diagnosis of tumor. For patients who had underwent the determination of serum CEA more than twice, CEA doubling time [DT] was also calculated. The serum CEA level and CEA DT of benign versusmalignant 18F-FDG PET-CT imaging results were compared
Results: thirty [25.00%] cases were finally diagnosed as malignant tumors, and 90 [75.00%] cases were excluded labelled benign condition. There was one false positive case and one false negative case each with 18F-FDG PET-CT diagnosis. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value were 96.7%, 98.9%, 98.3%, 96.7% and 98.9%, respectively. The serum CEA level of patients with positive 18F-FDG PET-CT imaging was higher than that of 18F-FDG PET-CT negative patients [p<0.001]. The serum CEA DT of patients with positive 18F-FDG PET-CT imaging was shorter than that of 18F-FDG PET-CT negative patients [p<0.001]. The receiver operating characteristic [ROC] curve analysis showed that the diagnostic efficacy of 18F-FDG PET-CT was best at serum CEA of 14.31 micro g/L
Conclusion: 18F-FDG PET-CT imaging has high diagnostic value for patients with elevated serum CEA. For patients with serum CEA over 14.31 micro g/L, the diagnostic value of 18F-FDG PET-CT for malignant tumors is more reliable
ABSTRACT
Objective To investigate the relative activity of multidrug resistance P-glycoprotein in the plasma of breast cancer patients, analyze the expression of P-glycoprotein before and after chemotherapy and evaluate its clinical value. Methods The plasma of patients and chemical reagents were mixed and distributed into the 96-well plate. The plate was read at 340 nm absorbaace before and after reaction. The variation of absorbance for each well was calculated, and then relative activity of each sample was compared to the referent compound activity. The relative activity of over 30 % was taken as positive expression of the P-gp for each sample. Results The frequency of P-glycoprotein expression was significantly increased from 16.2 % before chemotherapy to 43.2 % after chemotherapy (P<0.05). The positive expression of P-glycoprotein before and after chemotherapy were 5/6 and 9/16, respectively, in patients with positive lymph node metastasis, and 1/6 and 7/16, respectively, in patients with negative lymph node metastasis. Conclusion The results of this preliminary study suggest in P-glycoprotein expression in plasma of patients play an important role in the selection of drugs, which may be useful to evaluate the prognosis for treatment of breast cancer patients.