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Objective:To evaluate the effect of image-guided with cone-beam computed tomography (CBCT) based on volumetric modulated arc therapy (VMAT)-flattening filter free (FFF) on the setup errors of stereotactic body radiotherapy (SBRT) in patients with spinal metastatic tumors.Methods:The clinical data of 15 patients with spinal metastatic tumors who underwent SBRT in Jilin Cancer Hospital from August 2020 to January 2022 were retrospectively analyzed. The radiotherapy dose of bone metastasis was 32 Gy per 4 times and CBCT scanning was performed before and after radiotherapy. Every patient received radiotherapy 4 times; all 15 patients underwent SBRT 60 times in total and 120 CBCT volume images were finally obtained and analyzed. The systematic error (Σ) and random error (σ) were calculated at different correction threshold levels. The translational setup error and rotational setup error at the left-right (X axis), head-foot (Y axis) and front-back (Z axis) directions before and after radiotherapy were compared, which were expressed as Σ ± σ.Results:The pre-SBRT and post-SBRT translational setup errors were (0.14±0.27) cm and (0.07±0.19) cm, respectively ( P<0.001) in the X direction, (-0.05±0.33) cm and (0.00±0.19) cm, respectively ( P = 0.001) in the Y direction, (-0.13±0.19) cm and (-0.02±0.14) cm, respectively ( P = 0.012) in the Z direction. The pre-SBRT and post-SBRT rotational setup errors were (-0.31±0.76)° and (-0.09±0.34)°, respectively ( P < 0.001) in the X direction, (-0.13±0.88)° and (-0.07±0.36) °, respectively ( P < 0.001) in the Y direction, (0.10±0.51)° and (0.16±0.38)°, respectively ( P < 0.001) in the Z direction. Conclusions:CBCT correction could reduce Σ and σof the translational setup and rotational setup, increase the accuracy of SBRT based on VMAT-FFF for patients with spinal metastatic tumors.
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Objective:To compare the dosimetric differences between accelerated partial breast irradiation intensity modulated radiation therapy (APBI-IMRT) and whole breast irradiation with simultaneous integrated boost intensity modulated radiotherapy (WBI-SIB-IMRT) for early-stage breast cancer after breast-conserving surgery.Methods:A total of 35 patients with early-stage breast cancer in Jilin Province Cancer Hospital between July 2009 and December 2014 after breast-conserving surgery were enrolled. The targeted regions of APBI-IMRT and WBI-SIB-IMRT were created for each patient. The dosimetric difference comparison of the targeted region and normal tissues was evaluated by using dose volume histogram (DVH).Results:There was no significant difference in the dosimetric comparison of gross tumor volume (GTVtb) and planning gross tumor volume (PGTVtb) after correction of cumulative radiation effect (CRE) between WBI-SIB-IMRT group and APBI-IMRT group (both P > 0.05). The dose of clinical target volume (CTV) and planning target volume(PTV) in APBI-IMRT group was higher than that in WBI-SIB-IMRT group [CTV: (4 720±71) cGy vs. (3 889±79) cGy, t = 3.184, P = 0.027; PTV: (4 675±164) cGy vs. (3 807±199) cGy, t = 2.751, P = 0.032] after CRE correction. Compared with WBI-SIB-IMRT group, the dose of ipsilateral lung tissue and left heart tissue in APBI-IMRT group was decreased after CRE correction [(558.5±8.9) cGy vs. (1 304.9±34.4) cGy, t = -7.328, P = 0.001; (35.5±5.3) cGy vs. (843.0±41.5) cGy, t = -8.137, P = 0.001]. V 5/3.6 Gy, V 10/7.3 Gy, V 15/10.9 Gy, V 20/14.6 Gy, V 25/18.2 Gy and V 30/21.9 Gy of the ipsilateral lung and V 30/21.9Gy, V 40/29.2Gy of left heart in all breast cancer patients after two chemotherapy treatments had significant differences (all P = 0.001). Conclusion:Compared with WBI-SIB, APBI-IMRT can improve the dose distribution in target area and reduce the volume of high dose irradiation in organs at risk.
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Surgery,radiotherapy and chemotherapy are three traditional treatments for malignant tumors.With the development of medicine,immunotherapy has been gradually adopted as an emerging therapy of malignancies.Recent clinical studies have demonstrated that the combination of radiotherapy and immunotherapy can induce the abscopal effect and improve the prognosis of patients.Compared with the conventional radiotherapy,stereotactic radiotherapy has a larger single dose and higher accuracy,which is more likely to induce the bystander effect and anti-tumor response.The combination of stereotactic radiotherapy and immunotherapy has been proven to be a more promising therapy in certain clinical trials.However,not all types of tumors can benefit from such combined therapy in clinical practice.The optimal dose,fraction pattern and lesion of radiotherapy,immune enhancement and safety remain to be further clarified.In this article,the research progress,related controversies and future research direction of stereotactic radiotherapy combined with immunotherapy for malignancies were reviewed.
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Since the first application of whole brain radiation therapy (WBRT) to brain metastases in 1950 s,it has been regarded as a standard treatment for brain metastases of non-small cell lung cancer (NSCLC).Recently,more accurate radiotherapy technique and more effective systemic therapy have been developed.Especially,the molecular targeted drugs are upgraded rapidly with stronger targeting capability and better permeability of the central nervous system.With the prolonged survival of patients,long-term damage to the nervous system induced by WBRT causes widespread concerns.This article will review the related controversies and research progress in the application of WBRT to NSCLC with brain metastases in modern integrated therapy.
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Objective: To analyze the efficacy of apatinib in the treatment of a patient with lung squamous cell carcinoma who couldn' t tolerare the chemotherapy and review the literature, and to clarify the effectiveness of apatinib in order to provide the treatment reference. Methods: The patient was clearly diagnosed as stage Flung squamous cell carcinoma. After four cycles of chemotherapy, there was no significant change of the tumor volume, while the patient couldn' t tolerate the side effects caused by chemotherapy. Then the disease progressed rapidly. The primary lesion and multiple metastases responded significantly to the radiotherapy. However, the lesions were too extensive to radiotherapy, therefore, apatinib (500 mg • d-1, 40 d) was used to inhibit the progression of disease. Results: After the application of apatinib, the volumes of both lesions in chest wall and lung shrank greatly compared wtih before administration. The patient developed myelosuppression (grade E thrombocytopenia) and stopped taking apatinib. Then the volume of lesion in chest wall was increased. The dosage of apatinib reduced to 250 mg . d-1 , and the progression free survival (PFS) of the patient reached to 5 months. Conclusion: For the patients with lung squamous cell carcinoma who couldn ' t tolerate chemotherapy or fail in multiple lines of chemotherapy, apatinib has better efficacy with controllable side effects.