Role of positron emission tomography in the management of head and neck cancer in the molecular therapy era

Abstract

The utility of positron emission tomography-computed tomography has increasingly been studied during the last years. Positron emission tomography-computed tomography offers a holistic approach of cancer diagnosis as it can integrate structural, functional, metabolic, and molecular information of tumour. The technique offers three-dimensional, high-resolution, whole body, and quantitative imaging. 18F-Fluoro-2-deoxy-D-glucose still remains the only tracer widely available. Other tracers have been designed for assessment of proliferation, amino acid uptake, and hypoxia. 18F-Fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography seems the most appropriate technique for the assessment of locoregional lymph node involvement in head and neck cancer. False negativity of positron emission tomography-computed tomography in case of micrometastatic lymph node disease should be compensated by the implementation of the sentinel node scintigraphy guided biopsy. 18F-Fluoro-2-deoxy-D-glucose positron emission tomography-computed tomography has a very high sensitivity and negative predictive value in detecting residual disease after radiotherapy or early recurrent disease. Radiotherapy planning can use the 18F-fluoro-2-deoxy-D-glucose uptake distribution for increasing the accuracy of delineation of the target volumes in conformal radiotherapy. Positron emission tomography-computed tomography with other tracers such as deoxy-18F-fluorothymidine for proliferation mapping and [F-18] fluoromisonidazole for hypoxia mapping are currently being studied. Major studies have now confirmed the utility of positron emission tomography-computed tomography in the different phases of diagnostic and therapeutic phases of the management of patients with head and neck cancer.