Good agreements were obtained between the replicated measurements (interclass correlation coefficient > 0.99)
Except for MTT & TTP, which was statistically (p <0.05) lower in malignant lesions, all CTP parameter values were significantly (P <0 .05) higher in malignant lesions when compared with the benign lesions and the background lung parenchyma.
When compared to normal parenchyma, benign lesions showed higher BF and BV but were not statistically significant(p >0.05). MTT and TTP values in benign lesions were comparable to that of normal parenchyma.
Considerable differences with higher perfusion, PE and BV and lower TTP & MTT were noted in tumor ≤30mm than in tumor > 30mm. (p < 0.05).
All necrotic tumors showed inhomogeneity on non-contrast and enhanced scans.
Necrotic tumors represented statistically significantly lower BF, PEI, and BV compared with non-necrotic tumors (p < 0.05), but MTT and TTP longer than those of non-necrotic part of the necrotic tumors (p < 0.05).
FOLLOW UP CASES:
7 out of 9 followed-up patients had tumor volume reduction(median: -76%; 95%CI: 51-83) . BF , BV and MTT changes following therapy significantly correlated with tumor volume changes.
Trend to correlation was found between baseline tumor BF , BV , MTT and tumor volume changes(Spearman: R=.71, p= .0004 and R=.60, p=.004, respectively).
Rest of the 87 patients had palliative radiotherapy and had follow up CTp was, correlation between the CTp parameters and treatment response was assessed and showed: According to the RECIST criteria, responders were 17, and non-responders were 6.
Responsive tumors had significantly higher pre-CRT (chemo +/- radiotherapy) BF and BV (P < 0.05), and had significantly shorter pre-CRT MTT (P <0.05) than non-responsive tumors.
Tumor contraction rate showed a significant correlation with BF, BV (P <0.05) and MTT (P <0.05). Values of TTP and PEI did not show any significant difference in the two groups.