PURPOSE: In routine practice, the tumor response in head-and-neck cancer (HNC) is assessed 3-4 months after radiotherapy (RT). We compared the results of fluorodeoxyglucose-positron emission tomography (FDG-PET) during (47 Gy) and 4 months after RT. METHODS AND MATERIALS: In 40 patients with HNC, PET was performed before (PET1), at the end of Week 4 (47 Gy) (PET2), and 4 months after RT (PET3). Visual analysis classified patients as having a complete response (CR) or a non-CR (NCR). The sensitivity, specificity, accuracy, negative predictive value, and positive predictive value for PET2 and PET3 were determined. The 2-year overall survival (OS) rate for a CR and NCR was calculated for both response evaluation points. RESULTS: After a median follow-up of 26 months, 10 patients had died, 6 had residual disease, and 24 remained disease free. The overall sensitivity, specificity, negative predictive value, positive predictive value, and accuracy of PET2 vs. PET3 for the detection of a CR was 28.6%, 81.8%, 31.0%, 80.0%, and 42.5% vs. 78.6%, 75.0%, 60.0%, 88.0%, and 77.5%, respectively. The 2-year OS rate determined at 47 Gy was 90.0% and 71.8% for a CR and NCR, respectively, and did not appear to be significantly different (p = .50). For the study, at 4 months, the OS was significantly better in the CR group (91.8%) than in the NCR group (49.9%; p = .0055). CONCLUSION: The high specificity and positive predictive value for the evaluation of tumor response with PET2 and PET3 might avoid unnecessary salvage surgery in patients with a CR. In contrast to PET3, the sensitivity of PET 2 was low, and the difference in OS between the CR and NCR groups was not significantly different. Therefore, the evaluation of the tumor response with FDG-PET at 4 months after RT completion cannot be replaced by FDG-PET during RT at 47 Gy.
PURPOSE: In routine practice, the tumor response in head-and-neck cancer (HNC) is assessed 3-4 months after radiotherapy (RT). We compared the results of fluorodeoxyglucose-positron emission tomography (FDG-PET) during (47 Gy) and 4 months after RT. METHODS AND MATERIALS: In 40 patients with HNC, PET was performed before (PET1), at the end of Week 4 (47 Gy) (PET2), and 4 months after RT (PET3). Visual analysis classified patients as having a complete response (CR) or a non-CR (NCR). The sensitivity, specificity, accuracy, negative predictive value, and positive predictive value for PET2 and PET3 were determined. The 2-year overall survival (OS) rate for a CR and NCR was calculated for both response evaluation points. RESULTS: After a median follow-up of 26 months, 10 patients had died, 6 had residual disease, and 24 remained disease free. The overall sensitivity, specificity, negative predictive value, positive predictive value, and accuracy of PET2 vs. PET3 for the detection of a CR was 28.6%, 81.8%, 31.0%, 80.0%, and 42.5% vs. 78.6%, 75.0%, 60.0%, 88.0%, and 77.5%, respectively. The 2-year OS rate determined at 47 Gy was 90.0% and 71.8% for a CR and NCR, respectively, and did not appear to be significantly different (p = .50). For the study, at 4 months, the OS was significantly better in the CR group (91.8%) than in the NCR group (49.9%; p = .0055). CONCLUSION: The high specificity and positive predictive value for the evaluation of tumor response with PET2 and PET3 might avoid unnecessary salvage surgery in patients with a CR. In contrast to PET3, the sensitivity of PET 2 was low, and the difference in OS between the CR and NCR groups was not significantly different. Therefore, the evaluation of the tumor response with FDG-PET at 4 months after RT completion cannot be replaced by FDG-PET during RT at 47 Gy.
Authors: Philippe Lambin; Ruud G P M van Stiphout; Maud H W Starmans; Emmanuel Rios-Velazquez; Georgi Nalbantov; Hugo J W L Aerts; Erik Roelofs; Wouter van Elmpt; Paul C Boutros; Pierluigi Granone; Vincenzo Valentini; Adrian C Begg; Dirk De Ruysscher; Andre Dekker Journal: Nat Rev Clin Oncol Date: 2012-11-20 Impact factor: 66.675
Authors: Peter Lin; Myo Min; Mark Lee; Lois Holloway; Dion Forstner; Victoria Bray; Allan Fowler Journal: Eur J Nucl Med Mol Imaging Date: 2016-12-21 Impact factor: 9.236
Authors: Charlotte S Schouten; Remco de Bree; Lisa van der Putten; Daniel P Noij; Otto S Hoekstra; Emile F I Comans; Birgit I Witte; Patricia A Doornaert; C René Leemans; Jonas A Castelijns Journal: Quant Imaging Med Surg Date: 2014-08