Sun Z, et al. - The physicians conducted this study to assess the efficacy of neoadjuvant chemotherapy in patients with advanced gastric adenocarcinoma using low-dose computed tomography (CT) perfusion imaging technology and to determine whether any of the perfusion parameters could predict tumor response to chemotherapy. They concluded that low-dose CT perfusion imaging was a valuable tool that permitted microcirculation evaluation and thus, in patients with advanced gastric adenocarcinoma, could evaluate the efficacy of neoadjuvant chemotherapy.

• For this study, 40 patients with gastric adenocarcinoma (T3-4NxM0) received 3 cycles of neoadjuvant chemotherapy and low-dose spiral CT perfusion imaging prior to and after the first and third series of chemotherapy.
• Using commercial software, the physicians calculated tissue blood flow (BF) and blood volume (BV).
• They used one-way analysis of variance (ANOVA) to detect any significant variation of the tested parameters between different times of scanning.
• They used Spearman's test to assess the correlation among perfusion parameters, tumor size and pathological efficacy grade, and clinical response after chemotherapy, respectively.
• They used a receiver-operating characteristic analysis to determine the optimal diagnostic cutoff value for changes in perfusion parameters and tumor size.

• Between those before and after chemotherapy, one-way ANOVA demonstrated significant differences in BF and BV values (p < 0.01).
• After three series of chemotherapy, the BF, BV and size reduction rate were significantly correlated with pathological efficacy grade.
• After the first and third series of chemotherapy, BF and BV values were also significantly correlated with clinical response (p < 0.01, respectively).
• Compared with those of size reduction rate, the diagnostic sensitivity and specificity of the BV reduction rate were higher.