Objective To analyze the CT features of cavitation between primary lung adenocarcinoma and squamous cell cancer.Methods The CT findings of cavity of primary lung adenocarcinoma and squamous cell carcinoma were evaluated in 57 patients,including 33 of squamous cell carcinoma and 24 of adenocarcinoma.The clinical data and CT features were analyzed retrospectively using the independent samples t-test,Pearson Chi-square test or Fisher's exact test.Results The mean age of ptients with squamous cell carcinoma was higher than that of patients with adenocarcinoma (65.57-4-9.26 vs 58.75 ± 11.12,P =0.015).Statistical differences were found in distribution of gender and smoking habit between the two kinds of carcinomas (P =0.014 and P =0.029).The T stages were also different between the two carcinomas (P=0.003).In addition,the maximum diameter of tumor (P =0.003),the maximum diameter of cavity (P =0.029) and the maximum thickness of the cavity wall (P=0.001) of squamous cell carcinoma were higher than those of adenocarcinoma.Moreover,the presence of ground-glass opacity (P =0.010),vessel passing through the cavity (P =0.001),septum inside the cavity (P＜0.001) and tumoral bronchogram (P =0.027) in adenocarcinoma were higher than those in squamous cell carcinoma.Conclusion There are significant differences between adenocarcinoma and squamous cell carcinoma in the population distribution and image features,comprehensive analysis helps the differential diagnosis.

BACKGROUNDHigh-voltage analog X-ray examination is a main tool for pneumoconiosis, which is challenged by digital radiography (DR). The tube voltage of DR chest films required for diagnosis and staging of pneumoconiosis is concerned technically. We investigated the influence of the tube voltage on chest X-ray DR image quality of patients exposed to occupational dust.

METHODSDR images of the CDRAD2.0model, an anatomical chest phantom, and 136 exposed workers were analyzed at different tube voltages by threereaders. Image quality factors (IQF) were calculated and compared using the CDRAD2.0 model. DR images of ten anatomic positions were scored against those of the high-kilovolt chest films in anatomical phantom and clinical cases, and differences in scores were analyzed.

RESULTSIn the CDRAD2.0 model, all three readers had a minimal IQF at 120 kV (mean: 22.25 kV). The differences in the mean IQF of DR images at different tube voltages was significant (F = 13.78, P < 0.001). The IQF of DR imaging at 120 kV was similar to high kilovolt analog imaging (t = -0.58, P > 0.05). In the anatomic phantom and clinical cases, the DR images at 120 kV were closest in anatomical detail to the high kV analog images, and the means were similar (P > 0.05).

CONCLUSIONSAmong different tube voltages, DR image quality is closest to the high kilovolt analog images at 120 kV in patients exposed to occupational dust.

Adult ; Aged ; Environmental Pollution ; Female ; Humans ; Male ; Middle Aged ; Phantoms, Imaging ; Pneumoconiosis ; diagnosis ; Radiographic Image Enhancement ; methods ; Radiography, Thoracic