DCE-CT in lung cancer: perfusion characterisation of adenocarcinoma and squamous carcinoma subtypes

Purpose: To evaluate tumour baseline characteristics in blood flow (BF) values of two lung cancer subtypes, adenocarcinoma (AC) and squamous cell carcinoma (SCC). In addition, since literature shows discordant results, we also investigate possible motivations, so as to find out a clearer outcome. Methods and Materials: 27 patients (age range 36-81 years) with primary NSCLC, subdivided into 20 AC and 7 SCC, were enrolled in this study and underwent a CT perfusion at the diagnosis stage. BF values were computed according to the maximum slope method and values undergoing high fitting errors were automatically removed. The one-tail Welch's t-test (p<0.001) was employed for statistical assessment. Results: At baseline, mean BF values of AC group [81.4±30.1] result significantly greater than those of SCC subtype [59.6±31.7] (p<<10-5). Excluding unreliable BF values enforced the outcome. However, a few cases deviate from the mean value of the corresponding histological group. Two SCC lesions present a higher perfusion because of beam hardening artefacts coming from the pulmonary artery. Analogously, four AC cases show a lower perfusion, two of which are large and central lesions. The others, in the subpleural parenchyma, have a predominant pulmonary component underestimated by a delayed acquisition. Conclusion: At diagnosis, AC histological type has a significantly greater perfusion than SCC one. This clear behaviour may be attenuated by lesion position, central or peripheral, pulmonary artery artefacts and not appropriate acquisition protocol. Although these findings are clear, they should be enforced by a larger dataset, being of relevant importance for treatment strategies.