Role of perfusion computed tomography (CTp) for pretherapy assessment and induction chemotherapy monitoring (IC) in patients with squamous cell carcinoma (SCC) of the head and neck

e17015 Background: Reliable assessment of the response to IC is required to stratify further treatments, as responders are considered the best candidates for organ preservation strategies. We evaluated the role of CTp for pre-therapy assessment and IC monitoring in patients with SCC of the head and neck. METHODS: From November 2004, 28 consecutive patients with locally advanced SCC of the head and neck were enrolled, undergoing CTp and volumetric CT before and after IC with cisplatin, administered at a dose of 100 mg/m2 iv, on day 1, and 5-fluorouracil, administered at a dose of 1,000 mg/m2 ci from day 1 to day 5, q3wks for 2 or 3 cycles. Perfusion parameters were calculated for tumor: blood flow (BF), blood volume (BV), mean transit time (MTT) and capillary permeability-surface (PS). The Wilcoxon rank sum test was used to test for differences in the pre-therapy perfusion parameters between the different tumor grades, as well as between responders and nonresponders to IC. The post-therapy perfusion parameters were compared with the pre-therapy ones by the Wilcoxon signed rank test and percent changes in perfusion parameters were correlated with percent changes in tumor volume calculated by volumetric CT after IC by the Spearman correlation coefficient. RESULTS: Pre-therapy BF was significantly higher in G3 tumors, compared to G1 and G2 (p = 0.01) and G2 tumors (p = 0.03), and pre-therapy BV significantly higher in responders than in nonresponders (p = 0.01). Of the 20 patients who underwent post-therapy CTp, the 17 responders had significant reduction of BF (p = 0.003) and BV (p = 0.014) and increase of MTT (p = 0.04) in the post-therapy CTp, whereas the 3 non responders no significant changes in perfusion parameters. In the 17 responders, percent reduction in BF and BV showed correlation (Spearman R = 0.71, p = 0.0013 and R = 0.82, p = 0.00005, respectively) with percent reduction in tumor volume after IC. CONCLUSIONS: In our cohort of patients with SCC of the head and neck, CTp showed potential for pre-therapy assessment, as well as for IC monitoring; further studies are required to confirm our preliminary results. No significant financial relationships to disclose.