RESUMO
Esophageal cancer is one of the most common malignant tumors in the digestive tract. Its morbidity and mortality rates are high. Local advanced esophageal cancer relapses easily after operation and has a poor prognosis. Operation-based comprehensive treatment plays an important role in reducing the recurrence rate and increasing the survival rate. Radiotherapy is an important part of comprehensive treatment. From conventional radiotherapy two dimeusional conformal (2DCRT) to three dimensional conformal ra-diotherapy (3DCRT), intensity modulated radiation therapy (IMRT), image guide radiation therapy (IGRT), and volumetric modulated arc therapy (VMAT), radiotherapy technologies have experienced significant development. This development optimized the dose distri-bution and improved the accuracy of radiation. It has also provided a new understanding of the methods of radiotherapy, such as pre-operation radiotherapy, post-operation radiotherapy, and radiotherapy combined with chemotherapy. The progress of radiotherapy re-search on esophageal cancer is reviewed in this paper.
RESUMO
Glioma is the most frequently observed primary tumor of the central nervous system in adults. Among the glioma cases, more than three quarters of patients suffer from high-grade gliomas. High-grade glioma is not only a high-degree malignant tumor but is also an easily recurring disease after surgery with a very poor prognosis. Radiotherapy plus concomitant chemotherapy after operation is the standard treatment strategy for high-grade gliomas, which could increase the survival rate of patients. However, the curative effect is really not satisfactory because it could only guarantee a limited survival time. Over the recent years, molecular-targeted treatment has increasingly drawn the attention of scholars with the continuous development in glioma treatment, thereby becoming the hotspot among researchers. Vascular endothelial growth factor (VEGF) is highly expressed in glioma and in the tissues surrounding the cancer cells. VEGF could regulate tumor growth by inducing endothelial cell proliferation, growth, migration, and by increasing the vascular permeability. Hence, VEGF becomes an effective target for the treatment of glioma. Bevacizumab is a monoclonal antibody that can specifically prevent the combination of VEGF and its receptor, thereby inhibiting the formation of tumor blood vessels. At the same time, bevacizumab can normalize the tumor blood vessels, improve the permeability of blood vessels, and increase the effectiveness of drug concentration in the tumor tissues, thereby achieving anticancer efficacy. In this paper, the mechanism of bevacizumab is introduced. The research progress in the application of bevacizumab alone, as well as in combination with chemotherapy or other drugs, for the high-grade glioma treatment will be summarized.