There has been no established qualitative system of interpretation for therapy response assessment using PET/CT for head and neck cancers. The Cohen κ coefficient (κ) was determined to measure interreader agreement. Overall survival (OS) and progression-free survival (PFS) were analyzed by Kaplan-Meier plots having a Mantel-Cox log-rank test and Gehan Breslow Wilcoxon test for comparisons. Results Of the 214 individuals 175 were males and 39 were women. There was 85.98% 95.33% 93.46% and 87.38% agreement between the readers for overall remaining neck right neck and Tivozanib (AV-951) primary tumor site response scores respectively. The related κ coefficients for interreader agreement between readers were 0.69 0.68 0.69 and 0.79-0.86 for overall remaining neck right throat and main tumor site response respectively. The level of sensitivity specificity positive predictive value negative predictive value and overall accuracy of the therapy assessment were 68.1% 92.2% 71.1% 91.1% and 86.9% respectively. Cox multivariate regression analysis showed human being papillomavirus (HPV) status and PET/CT interpretation were the only factors associated with PFS and OS. Among the HPV-positive individuals (= 123) there was Tivozanib (AV-951) a significant difference in PFS (risk percentage [HR] 0.14 95 confidence interval 0.03 = 0.0063) and OS (HR 0.01 95 confidence interval 0 = 0.0006) between the individuals who had a score negative for residual tumor versus positive for residual tumor. A similar significant difference was observed in PFS and OS for those individuals. There was also a significant difference in the PFS of individuals with PET-avid residual disease in one site versus multiple sites in the neck (HR 0.23 log-rank = 0.004). Summary The Hopkins 5-point qualitative therapy response interpretation criteria for head and neck PET/CT has considerable interreader agreement and excellent bad predictive Tivozanib (AV-951) value and predicts OS and PFS in individuals with HPV-positive HNSCC. = 214) The median follow-up of the study human population was 27 mo (range 1 mo) from your date of the PET/CT study and 38 individuals (17.7%) died within the period of the study. Of the 214 individuals 63 were found to have disease progression during the follow-up period from your Tivozanib (AV-951) date of the check out to death or the last patient encounter at our institution. Of these progression was confirmed in 25 (39.7%) individuals by tissue analysis and 38 (60.3%) individuals by imaging and clinical follow-up. The average duration to progression from your date of the scan was 10.8 ± 11.5 mo. The median survival of the 45 positive individuals was 16 mo (range 2 mo) and 19 individuals (42.2%) died within this group. In contrast in the overall negative PET/CT group the median survival was 29 mo (range 1 mo) and 18 individuals (10.6%) died with this group. The Kaplan-Meier survival analysis showed a significant difference in the overall survival (OS) between individuals who were classified bad for residual tumor from the 5-point scale interpretation compared with those who were obtained positive for residual Tivozanib (AV-951) tumor (log-rank Mantel-Cox < 0.0001) having a risk percentage (HR) of 0.046 (95% confidence interval [CI] 0.018 (Fig. 3). For progression-free survival (PFS) the Kaplan-Meier survival analysis also showed a significant difference between individuals who were obtained bad for residual tumor compared with those who were obtained positive for residual tumor (log-rank Mantel-Cox < 0.0001) with an HR of 0.05 (95% CI 0.02 (Fig. 3). FIGURE 3 Kaplan-Meier survival curves for those individuals. OS (A) and PFS (B) differed significantly between individuals with negative PET result (score 1-3) and positive PET result (score 4 or 5 5) relating to therapy assessment scoring system. There was no significant difference between the OS of the individuals who experienced residual disease at a single site in the neck (main site or right side throat or left part neck) and those with multiple sites of residual disease (log-rank Mantel-Cox = 0.072) with an HR of 0.38 (95% CI 0.13 However there was a significant difference in the PFS between these 2 groups of individuals (log-rank Mantel-Cox = 0.004) with an HR of 0.23 (95% CI 0.085 (Fig. 4). Number 4 Kaplan-Meier survival curves Rabbit Polyclonal to Prostate-specific Antigen. for individuals with 18F-FDG-avid lesions at solitary site (main site or ideal neck or remaining throat) versus multiple sites. (A) OS did not display significant difference between the 2 organizations. Tivozanib (AV-951) (B) PFS differed significantly … Kaplan-Meier Survival Curves: Therapy Assessment Score and Survival End result in HPV-Positive Individuals (= 123) Among the 214 individuals included in the study 123 individuals experienced a positive HPV test. Among these 16 (13.0%) were positive and 107 (87.0%).