Mischa de Ridder1,2, Zeno A R Gouw1, Arash Navran1, Olga Hamming-Vrieze1, Bas Jasperse3, Michiel W M van den Brekel4,5, Wouter V Vogel1,6, A Al-Mamgani7. 1. Department of Radiation Oncology, Antoni van Leeuwenhoek - Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands. 2. Department of Radiation Oncology, Verbeeten Instituut, Tilburg, The Netherlands. 3. Department of Radiology, Antoni van Leeuwenhoek/Netherlands Cancer Institute Amsterdam, Amsterdam, The Netherlands. 4. Department of Head and Neck Surgery, Antoni van Leeuwenhoek/Netherlands Cancer Institute Amsterdam, Amsterdam, The Netherlands. 5. Amsterdam UMC, Department of Maxillo-facial Surgery, University of Amsterdam, Amsterdam, The Netherlands. 6. Department of Nuclear Medicine, Antoni van Leeuwenhoek/Netherlands Cancer Institute Amsterdam, Amsterdam, The Netherlands. 7. Department of Radiation Oncology, Antoni van Leeuwenhoek - Netherlands Cancer Institute, Plesmanlaan 121, 1066 CX, Amsterdam, The Netherlands. a.almamgani@nki.nl.
Abstract
PURPOSE: Early detection of residual disease (RD) after (chemo)radiation for oropharyngeal (OPC) is crucial. Surveillance of neck nodes with FDG-PET/CT has been studied extensively, whereas its value for local RD remains less clear. We aim to evaluate the diagnostic value of post-treatment FDG-PET/CT in detecting local RD and the outcome of patients with local RD. METHODS: A cohort (n = 352) of consecutively treated OPC patients at our institute between 2010 and 2017 was evaluated. Patients that underwent FDG-PET/CT at 3 months post-treatment (n = 94) were classified as having complete (CMR) or partial metabolic response (PMR). PMR was defined as visually detectable metabolic activity above the background of surrounding normal tissues. Primary endpoint was diagnostic accuracy in detecting local RD. RESULTS: Local RD was seen in 19/352 patients (5%), all of them were HPV negative. The FDG-PET/CT had a sensitivity of 100% (8/8), specificity 85% (73/86), PPV 38% (8/21), NPV 100% (73/73), and accuracy 86%. Patients with local RD had significantly worse OS at 2 years, compared to those without (10 versus 88%, P < 0.001). In multivariable analysis, local RD remained a significant predictive factor for death with a hazard ratio of 11.9 (95% CI 5.8-24.3). The number of patients that underwent PET/CT increased over time (P < 0.001), whereas the number of patients that underwent EUA declined (P = 0.072). CONCLUSION: FDG-PET/CT has excellent performance for the detection of RD, with the sensitivity and negative predictive value approaching 100%. Due to these excellent results is examination under anaesthesia today in the vast majority of the PET-negative cases not necessary anymore.
PURPOSE: Early detection of residual disease (RD) after (chemo)radiation for oropharyngeal (OPC) is crucial. Surveillance of neck nodes with FDG-PET/CT has been studied extensively, whereas its value for local RD remains less clear. We aim to evaluate the diagnostic value of post-treatment FDG-PET/CT in detecting local RD and the outcome of patients with local RD. METHODS: A cohort (n = 352) of consecutively treated OPC patients at our institute between 2010 and 2017 was evaluated. Patients that underwent FDG-PET/CT at 3 months post-treatment (n = 94) were classified as having complete (CMR) or partial metabolic response (PMR). PMR was defined as visually detectable metabolic activity above the background of surrounding normal tissues. Primary endpoint was diagnostic accuracy in detecting local RD. RESULTS: Local RD was seen in 19/352 patients (5%), all of them were HPV negative. The FDG-PET/CT had a sensitivity of 100% (8/8), specificity 85% (73/86), PPV 38% (8/21), NPV 100% (73/73), and accuracy 86%. Patients with local RD had significantly worse OS at 2 years, compared to those without (10 versus 88%, P < 0.001). In multivariable analysis, local RD remained a significant predictive factor for death with a hazard ratio of 11.9 (95% CI 5.8-24.3). The number of patients that underwent PET/CT increased over time (P < 0.001), whereas the number of patients that underwent EUA declined (P = 0.072). CONCLUSION: FDG-PET/CT has excellent performance for the detection of RD, with the sensitivity and negative predictive value approaching 100%. Due to these excellent results is examination under anaesthesia today in the vast majority of the PET-negative cases not necessary anymore.
Entities:
Keywords:
Chemoradiation; Head and neck; Oropharynx; PET/CT; Radiotherapy; Recurrence
Authors: Melvin L K Chua; Daniel J Ma; Carryn M Anderson; Sana D Karam; Danielle N Margalit; Randall J Kimple Journal: Adv Radiat Oncol Date: 2020-05-15