Perfusion Computed Tomography in Predicting Treatment Response of Advanced Esophageal Squamous Cell Carcinomas

Background: The purpose of this study was to prospectively evaluate the predictive value of perfusioncomputed tomography (CT) for response of local advanced esophageal carcinoma to radiotherapy andchemotherapy. Materials and
Methods: Before any treatment, forty-three local advanced esophageal squamouscell carcinomas were prospectively evaluated by perfusion scan with 16-row CT from June 2009 to January 2012.Perfusion parameters, including perfusion (BF), peak enhanced density (PED), blood volume (BV), and time topeak (TTP) were measured using Philips perfusion software. Seventeen cases received definitive radiotherapyand 26 received concurrent chemo-radiotherapy. The response was evaluated by CT scan and esophagography.Differences in perfusion parameters between responders and non-responders were analyzed, and ROCs were usedto assess predictive value of the baseline parameters for treatment response.
Results: There were 25 responders(R) and 18 non-responders (NR). Responders showed significantly higher BF (R:34.1 ml/100g/min vs NR: 25.0ml/100g/min, p=0.001), BV (23.2 ml/100g vs 18.3 ml/100g, p=0.009) and PED (32.5 HU vs 28.32HU, P=0.003) thannon-responders. But the baseline TTP (R: 38.2s vs NR: 44.10s, p=0.172) had no difference in the two groups.For baseline BF, a threshold of 36.1 ml/100g/min achieved a sensitivity of 56%, and a specificity of 94.4% fordetection of clinical responders from non-responders.
Conclusions: The results suggest that the perfusion CTcan provide some helpful information for identifying tumors that may respond to radio-chemotherapy.