ABSTRACT
Objective:To investigate the value of 18F-FDG PET/CT metabolic parameters in predicting perineural invasion (PNI) in patients with non-metastatic rectal cancer. Methods:From August 2012 to April 2020, 81 patients (51 males, 30 females, median age: 63 years) who received PET/CT examination and pathologically confirmed as rectal cancer in the Affiliated Hospital of Qingdao University were retrospectively analyzed. The 18F-FDG PET/CT metabolic parameters including SUV max, metabolic tumor volume (MTV) and total lesion glycolysis (TLG), and clinicopathological factors including gender, age, carcinoembryonic antigen (CEA), carbohydrate antigen (CA)19-9, maximum tumor diameter, degree of differentiation, T stage, lymph node metastasis, and TNM stage were recorded. Mann-Whitney U test and χ2 test were used to compare the differences of each parameter between PNI positive group and PNI negative group. Multivariate logistic regression was used to analyze the independent predictor of positive PNI. ROC curve was used to analyze its predictive efficacy. Results:Of 81 patients, 32(39.51%) were PNI positive and 49(60.49%) were PNI negative. There were significant differences of T stage ( χ2=10.73, P=0.010), lymph node metastasis ( χ2=6.21, P=0.013), TNM stage ( χ2=7.61, P=0.022), MTV (14.6(10.4, 24.7)and 9.0(5.4, 14.5) cm 3; U=-3.48, P=0.001) and TLG (108.588(72.749, 182.707) and 65.365(35.593, 117.682) g; U=-2.79, P=0.005) between PNI positive group and PNI negative group. Multivariate logistic regression analysis showed that MTV was the independent predictor of positive PNI in non-metastatic rectal cancer patients (odds ratio ( OR)=1.130, 95% CI: 1.025-1.245, P=0.014). The optimal threshold of MTV was 9.53 cm 3 and AUC was 0.73 with the sensitivity of 81.82%(27/33) and the specificity of 59.18%(29/49). Conclusion:18F-FDG PET/CT metabolic parameter MTV can predict PNI in non-metastatic rectal cancer with high sensitivity.
ABSTRACT
BACKGROUND:Buffy-coat-derived platelet concentrates and plasma-rich platelet concentrates have a high incidence of invalid infusion and adverse reactions. OBJECTIVE:To observe the improved preparation of buffy-coat-derived platelet concentrates and to analyze the influential factors relevant to platelet recovery. METHODS:400 mL of blood sample extracted from 126 cases were randomly divided into improved buffy-coat group, buffer-coat group and platelet-rich plasma after 4-6 hours. The 3-step centrifugal method was used for improved preparation of buffy-coat-derived platelet concentrates:step 1, centrifugation at 2 300 r/min for 12 minutes at (22±2)℃ with a deceleration of 5;step 2, centrifugation at 910 r/min for 10 minutes at (22±2)℃;step 3, centrifugation at 2 800 r/min for 12 minutes at (22±2)℃. After centrifugation, the upper layer containing few platelets was removed, and the rest 30 mL platelet suspension was platelet concentrates. Factors affecting platelet recovery were analyzed through literature retrieval. RESULTS AND CONCLUSION:There was no difference in platelet number among the three groups before preparation of platelet concentrates (P>0.05). A higher rate of platelet recovery was found in the platelet-rich plasma group and improved buffy-coat group compared with the buffy-coat group (P0.05). There were less residual red blood cells and white blood cells in the two buffy-coat groups than the platelet-rich plasma group (P0.05). The recovery rate of prepared platelet concentrates was affected by the whole blood amount, centrifugal speed, centrifugation time and methods. Improved buffy-coat method for preparation of platelet concentrates can be generalized in blood centers or blood stations, because it can reduce residual red blood cells and white blood cells and increase rate of platelet recovery.