HRCT Signs of Peripheral Lung Cancer: Its Value in Differentiating Squamous Carcinoma with Adenocarcinoma

Objective To evaluate HRCT signs in differentiating peripheral pulmonary squamous carcinoma with adenocarcinoma.Materials and Methods HRCT features of 54 cases with peripheral pulmonary squamous carcinoma and 67 cases with adenocarcinoma were retrospectively analyzed.Results (1) The mean diameter of peripheral pulmonary squamous carcinoma was significantly larger than that of adenocarcinoma (P=0.000). (2) The occurrence of deep lobulation sign, focal necrosis and widened-base attached to thoracic wall was markedly higher in peripheral pulmonary squamous carcinoma than in adenocarcinoma (P=0.000, P=0.000 and P=0.005, respectively). (3) The occurrence of pleural indentation was obviously higher in peripheral pulmonary squamous carcinoma than in adenocarcinoma (P=0.006). (4) No significant difference in the occurrence of vacuole sign, air bronchogram, broncho-vessel convergence sign, spicule sign and spinous sign was found between squamous carcinoma and adenocarcinoma (P0.05).Conclusion HRCT can display lung cancer's signs in detail. When three or two of the following sings, i.e. the deep lobulation sign, focal necrosis and widened base attached to thoracic wall, are coexisted, the diagnostic specificity for peripheral pulmonary squamous carcinoma will be up to 90%～100%.