肺腺癌实性结节肿瘤间质与多排螺旋CT早期增强间的关系研究

The correlation between stroma analysis and MDCT early phase contrast enhancement in small solid lung adenocarcinoma

Objective: To evaluate correlations between proportion and distribution of tumor stroma and MDCT early phase enhancement character in solid lung adenocarcinoma, and compare with microvessel density and histological subtypes.Methods: Thirty-one patients with lung adenocarcinoma shown as solid solitary pulmonary nodules underwent routine contrast-enhanced MDCT followed by surgical resections. CT character included net enhancement and distribution of enhancement. The largest cut surface of tumor specimens were stained by hematoxylin and eosin. About 25 fields of view of each specimen were scanned as digitized pictures at low magnification. Semi-auto segmentation software was used to calculate mean stroma proportion. Pearson correlation coefficient was used to represent the relationships between extent of tumor enhancement, proportion of tumor stroma and MVD respectively. Fisher's exact test was used to analyze statistical differences in degree of CT enhancement among groups of different histological subtypes. Results: Proportion of invasive tumor stroma (13.2%-54.5%, mean 26.2 ± 8.8%) was correlated positively with net enhancement (8-60.8 HU, mean 31.2 ± 13.6 HU; r =0.483, P= 0.006) which was more than MVD. 58.1% cases showed homogenous enhancement, 32.3% cases showed peripheral inhomogenous enhancement, 3.2% cases showed central inhomogenous enhancement, 3.2% cases showed asymmetrical inhomogenous enhancement, and 3.2% cases showed no enhancement. 58.1% cases' stroma showed mixed distribution,35.5% cases showed peripheral distribution, 3.2% cases showed central distribution, and 3.2% cases showed asymmetrical distribution. Significantly more adenocarcinomas classified with "net enhancement ＞ 20 HU" were found in the acinar group than in the solid with mucin subtype (P = 0.005). Conclusion: Extent of CT enhancement reflects underlying not only the tumor angiogenesis but also stroma proliferation in solid small lung adenocarcinoma. Tumor stroma proportion could reflect the histopathologic basis of small lung adenocarcinoma's CT enhancement substantially than MVD. Distribution between enhancement and tumor stroma have good correspondence. Most of acinar adenocarcinomas have higher degree of CT net enhancement than solid with mucin adenocarcinomas.