Comparison by dynamic enhancement in spiral CT to differentiate peripheral squamous cell carcinoma from adenocarcinoma of the lung

Objective To compare the manifestations of peripheral lung squamous cell carcinoma by CT dynamic enhancement with that of adenocarcinoma, and evaluate the difference of CT dynamic enhancement to distinguish peripheral lung squamous cell carcinomas from adenocarcinoma. Methods Thirty peripheral lung squamous cell carcinomas and 40 adenocarcinomas were examined with dynamic contrasted CT, enhancement at various phases recorded, based on which the time-intensity curves were produced. The enhancement patterns were compared and analyzed. Results There was no statistically significant difference in the enhancement degree and peak time between peripheral lung squamous cell carcinoma and adenocarcinoma (P0.05). The difference in enhancement pattern between these two different types of carcinoma was not statistically significant when the lesion was larger than 3 cm in diameter(P0.05), whereas it became statistically significant when the lesion is less than 3 cm (P0.05). Most of the squamous cell carcinoma showed heterogenous enhancement or peripheral enhancement in the tumor zone, however, most of the adenocarcinomas had homogenous enhancement. Conclusion The maximum enhancement and the peak time are not helpful in differentiating peripheral lung squamous cell carcinoma from adenocarcinoma. When the lesion is less than 3 cm in diameter, the enhancement pattern of peripheral squamous cell carcinomas is different from that of adenocarcinoma.