Optimal postoperative surveillance strategies for cancer survivors with gastric neuroendocrine carcinoma based on individual risk: a multicenter real-world cohort study.

BACKGROUND: The best follow-up strategy for cancer survivors after treatment should balance the effectiveness and cost of disease detection while detecting recurrence as early as possible. Due to the low incidence of gastric neuroendocrine carcinoma and mixed adenoneuroendocrine carcinoma [G-(MA)NEC], high-level evidence-based follow-up strategies is limited. Currently, there is a lack of consensus among clinical practice guidelines regarding the appropriate follow-up strategies for patients with resectable G-(MA)NEC. MATERIALS AND METHODS: The study included patients diagnosed with G-(MA)NEC from 21 centers in China. The random forest survival model simulated the monthly probability of recurrence to establish an optimal surveillance schedule maximizing the power of detecting recurrence at each follow-up. The power and cost-effectiveness were compared with the National Comprehensive Cancer Network, European Neuroendocrine Tumor Society, and European Society for Medical Oncology Guidelines. RESULTS: A total of 801 patients with G-(MA)NEC were included. The patients were stratified into four distinct risk groups utilizing the modified TNM staging system. The study cohort comprised 106 (13.2%), 120 (15.0%), 379 (47.3%), and 196 cases (24.5%) for modified groups IIA, IIB, IIIA, and IIIB, respectively. Based on the monthly probability of disease recurrence, the authors established four distinct follow-up strategies for each risk group. The total number of follow-ups 5 years after surgery in the four groups was 12, 12, 13, and 13 times, respectively. The risk-based follow-up strategies demonstrated improved detection efficiency compared to existing clinical guidelines. Further Markov decision-analytic models verified that the risk-based follow-up strategies were better and more cost-effective than the control strategy recommended by the guidelines. CONCLUSIONS: This study developed four different monitoring strategies based on individualized risks for patients with G-(MA)NEC, which may improve the detection power at each visit and were more economical, effective. Even though our results are limited by the biases related to the retrospective study design, we believe that, in the absence of a randomized clinical trial, our findings should be considered when recommending follow-up strategies for G-(MA)NEC.

Clinical significance of expression of proliferating cell nuclear antigen and E-cadherin in gastric carcinoma.

AIM: to investigate the expression of proliferating cell nuclear antigen (PCNA) and E-cadherin in gastric carcinoma and to analyze their clinical significance. METHODS: A total of 146 patients were selected for this study, including 38 patients with intestinal metaplasia, 42 with dysplasia, and 66 with primary gastric cancer. In addition, 40 patients with normal gastric tissues were selected as controls. The expression of PCNA and E-cadherin was detected by immunohistochemistry. Differences in PCNA and the E-cadherin labeling indexes among normal gastric mucosa, intestinal metaplasia, dysplasia, and gastric carcinoma were compared. Subjects with normal gastric tissues were assigned to a normal group, while gastric cancer patients were assigned to a gastric cancer group. The difference in PCNA and E-cadherin expression between these two groups was compared. The relationship between expression of PCNA and E-cadherin and clinicopathological features was also explored in gastric cancer patients. Furthermore, prognosis-related factors, as well as the expression of PCNA and E-cadherin, were analyzed in patients with gastric cancer to determine the 3-year survival of these patients. RESULTS: The difference in PCNA and the E-cadherin labeling indexes among normal gastric mucosa, intestinal metaplasia, dysplasia, and gastric carcinoma was statistically significant (P < 0.05). During the transition of normal gastric mucosa to gastric cancer, the PCNA labeling index gradually increased, while the E-cadherin labeling index gradually decreased (P < 0.05). The PCNA labeling index was significantly higher and the E-cadherin labeling index was significantly lower in gastric cancer than in dysplasia (P < 0.05). The expression of PCNA was significantly higher in the gastric cancer group than in the normal group, but E-cadherin was weaker (P < 0.05). There was a negative correlation between the expression of PCNA and E-cadherin in gastric carcinoma (r = -0.741, P = 0.000). PCNA expression differed significantly between gastric cancer patients with and without lymph node metastasis and between patients at different T stages. E-cadherin expression also differed significantly between gastric cancer patients with and without lymph node metastasis (P < 0.05). High T stage and positive PCNA expression were risk factors for the prognosis of patients with gastric cancer (RR > 1), while the positive expression of E-cadherin was a protective factor (RR < 1). The sensitivity, specificity, and accuracy of PCNA positivity in predicting the 3-year survival of patients with gastric cancer were 93.33%, 38.89%, and 0.64, respectively; while these values for E-cadherin negativity were 80.0%, 41.67%, and 0.59, respectively. When PCNA positivity and E-cadherin negativity were combined, the sensitivity, specificity, and accuracy were 66.67%, 66.67%, and 0.67, respectively. CONCLUSION: Combined detection of PCNA and E-cadherin can improve the accuracy of assessing the prognosis of patients with gastric cancer.

Love-mode surface acoustic wave devices based on multilayers of TeO2/ZnO(112¯0)/Si(100) with high sensitivity and temperature stability.

A multilayer structure of TeO2/interdigital transducers (IDTs)/ZnO(112¯0)/Si(100) was proposed and investigated to achieve both high sensitivity and temperature-stability for bio-sensing applications. Dispersions of phase velocities, electromechanical coupling coefficients K2, temperature coefficient of delay (TCD) and sensitivity in the multilayer structures were simulated as functions of normalized thicknesses of ZnO (hZnO/λ) and TeO2 (hTeO2/λ) films. The fundamental mode of Love mode (LM) - surface acoustic wave (SAW) shows a larger value of K2 and higher sensitivity compared with those of the first mode. TeO2 film with a positive TCD not only compensates the temperature effect induced due to the negative TCD of ZnO(112¯0)/Si(100), but also enhances the sensitivity of the love mode device. The optimal normalized thickness ratios were identified to be hTeO2/λ=0.021 and hZnO/λ=0.304, and the devices with such structures can which generate a normalized sensitivity of -1.04×10-3m3/kg, a TCD of 0.009ppm/°C, and a K2 value of 2.76%.