ABSTRACT
Chimeric antigen receptor T (CAR-T) cell therapy is one of the most significant advances in cancer treatment in the last few decades, revolutionizing the treatment paradigm for patients with refractory / recurrent diffuse large B-cell lymphoma (R/R DLBCL) and effectively improving the survival rate of these patients. However, due to the high incidence of grade III-IV side effects of CAR-T cell therapy and the fact that some patients did not obtain remission after CAR-T cell therapy or developed rapid disease progression within a short period of time, researchers are attempting to explore combined therapies, such as chemotherapy, radiotherapy and immunotherapy, to reduce the incidence of side effects and prolong the duration of persistent remission in patients. Among these options, radiotherapy in combination with CAR-T cell therapy have been proven to improve clinical prognosis. In this article, the theoretical basis of synergistic treatment of radiotherapy and CAR-T cell therapy in patients with R/R DLBCL, the safety and efficacy of radiotherapy, the sequence of radiotherapy and CAR-T cell therapy, and the dose of the target area of radiotherapy were reviewed, aiming to provide more evidence for the application and optimization of radiotherapy combined with CAR-T cell therapy for R/R DLBCL.
ABSTRACT
Objective To study the impact of local fractionated irradiation on lung metastasis in H22-bearing mice, and to explore its mechanism involved. Methods Subcutaneous transplantation tumor model bearing with H22 was established. Mice were divided into three groups as healthy control, tumor control and irradiation groups. The size of subcutaneous tumors was measured and lung metastasis was observed. The expressions of PCNA, VEGF and MVD were detected immunohistochemically. The plasma levels of CD4 and CD8 were determined by using flow cytometry. Results The tumor size in irradiated group was smaller than that in tumor control group. The tumor inhibition rate in irradiated group was 30%.Lung metastasis in irradiated group was more severe than that in tumor control group (x2 = 8.31,4.48,9. 60, P＜ 0.05 ). The expressions of PCNA, VEGF and MVD in two groups were statistically different( t =23.78,-2.47, -6.43, P ＜ 0. 05). The levels of CD4 and CD8 in irradiated group were statistically different compared to healthy control group ( t = 4. 72 and 3.31, P＜ 0.05 ). Conclusions For the H22 model, radiation might inhibit the local transplantation tumor, but increase the risk of lung metastasis.
ABSTRACT
Objective We have monitored the set up errors of radiotherapy for thoracic cancer using ontime imaging system. The discrepancy of couch top between treatment machine (net bracket) and simulator (plate) was observed. Set up errors were analyzed quantitively according to variable distribution, ratio and extent of displacement. Methods Three hundred eighty nine orthogonal portal images of 30 patients were compared to the simulation films. Set up deviation in lateral, longitudinal and vertical direction were measured respectively. The systematic and random errors were evaluated. Results The distribution of set up errors in each direction approximated a normal distribution. The systematic error in lateral and longitudinal was lower with a mean of 1～2 mm, and however, it was 6.8 mm in vertical direction without immobilization device as compared to 1.5 mm with immobilization device. The random error was larger and ratio of vertical displacement was higher without immobilization. Conclusions The decline of treatment couch top (with net bracket) could result in a larger systematic error with a mean of 6.8 mm. We must pay attention to the coordination of couch top between treatment machine and simulator when radiation field is set. The use of immobilization device during thoracic radiotherapy is able to improve the geometrical quality.