Application of 4DCT-based lung functional imaging in radiotherapy for lung cancer / 中华放射肿瘤学杂志

Radiation pneumonia is a side effect that cannot be ignored in the current radiation therapy for lung cancer. At present, there are studies and reports of the introduction of functional imaging technology into lung cancer radiotherapy plans, in which 4DCT has better application prospects in radiotherapy for lung cancer because of its advantages of simple operation, high spatial resolution and no additional cost, etc. Compared with single-photon emission computed tomography (SPECT)-CT, positron emission tomography (PET)-CT, MRI has a better application prospect in radiotherapy of lung cancer. The use of 4DCT to obtain the patient's lung function status can predict radiation pulmonary toxicity and assist clinicians to deliver prompt interventions. Moreover, it can help carry out radiotherapy for functional lung avoidance, mitigate the damage of normal lung tissues, and alleviate chest toxicity, which may have wider application value in the future. In this article, research progress on functional lung imaging algorithms based on 4DCT and the application of radiation therapy for lung cancer was reviewed.

Impacts of different tracking methods on short-term therapeutic effect of cyberknife in treatment of lung cancer / 中华放射肿瘤学杂志

Objective To investigate the impacts of fiducial tracking and X-sight tracking on the short-term therapeutic effect of cybernikife in the treatment of lung cancer.Methods Retrospective analysis was performed on 64 lung cancer patients (72 lesions),including 40 primary tumor patients (41 lesions) and 24 metastatic tumor patients (31 lesions),who were treated with cyberknife.Fiducial tracking was used for 45 lesions,while X-sight tracking was used for 27 lesions.The planning target volume was covered by 70％-94％ (median 80％) isodose contour.The irradiation dose was 60 Gy/3 fractions.The relationship between short-term therapeutic effect and tracking method was determined.Results Overall,the lesions undergoing fiducial tracking showed significantly higher response rate than those undergoing X-sight tracking (93％ vs.74％,x2 =6.84,P=0.033),and so was in lower lung lesions (15％ vs.7％,x2 ＝7.18,P=0.028).But the two tracking methods achieved similar effects in upper lung lesions (28％ vs.12％,x2 =2.36,P =0.310).In the lesions with treatment volumes smaller than 15 cm3,the fiducial tracking achieved significantly higher response rate than the X-sight tracking (25 ％ vs.12％,x2 =6.53,P =0.038),but the two tracking methods achieved similar effects in the lesions with treatment volumes not smaller than 15 cm3 (17％ vs 8％,x2 =1.57,P =0.460).Overall,the lesions undergoing X-sight tracking had significantly highertreatment failure rate than fiducial tracking (1 9 ％ vs.2 ％,x2 =6.33,P =0.021).Conclusions Different tracking methods may lead to different therapeutic effects of cyberknife in the treatment of lung cancer,which are related to lesion location and treatment volume.