Objective To evaluate the efficacy of CT in diagnosis of pulmonary blastoma (PB).Methods 10 patients with surgically and pathologically proved PB were collected in this study,and CT findings of the tumors were retrospectively analyzed. Results Of 10 cases,1 were central form (the tumors localized under pleura) and 9 was periphery form.The tumors were localized at right lobus in 6( including upper lobus,middle and lower lobus in 1,1 and 4,respectively) and left lobus in 4(upper lobus in 3 and lower lobus in one).The lesions were more than 3 cm in diameters in all cases.Necrosis of tumors were seen in 7 cases.The lesions had obvious enhancement after intravenous injection of contrast medium.Enlarged lymph nodes were identified at hilum of the lung and mediastinum in one,bony destruction and distant metastases were seen in one and 2,respectively.Conclusion PB is not of characteristic CT features,CT-guided percutaneous needle biopsy and the immunohistochemical method are helpful to the diagnosis of pulmonary blastoma.

ObjectiveTo analyze the application value of diffusion-weighted magnetic resonance imaging (DWMRI) in gross tumor volume (GTV) delineation of esophageal squamous cell carcinoma (SCC).MethodsTwenty-nine patients with esophageal SCC treated with radical surgery were analyzed.Routine CT scan,MRI T2-weighted and DWMRI were employed before surgery;diffusion-sensitive gradient b-values were taken 400,600 and 800 s/mm2.GTVs were delineated using CT,MRI T2-weighted images and DWMRI under different b-value images.The length of GTVs measured under different images was compared with the pathological length and confirm the most accurate imaging condition.Use radiotherapy planning system to fuse DWMRI images and CT images to investigate the possibility of delineate GTVs on fused images.ResultsThe difference of GTV length value between CT,T2 WI images and specimen was 3.36 mm and 2.84 mm.When b =400,600 and 800 s/mm2,the difference between GTV length value on the DWMRI images and on specimen was 0.47 mm,-0.47 mm and - 1.53 mm;the correlation coefficient of the measuring esophageal lengths on DWMRI images and the pathological lengths was 0.928,0.927 and 0.938.DWMRI images and CT images could fuse accurately on radiotherapy planning system.GTV margin could.show clearly on fused images.ConclusionsDWMRI images can display the esophageal carcinoma lengths and margin accurately.When DWMRI images fused with CT images,GTV margin could show clearly,it can be used to delineate GTV accurately.