Comparative study of F18 FDG PET CT Metabolic Volume Vs Anatomical Volume in Extracranial Head and Neck Malignancies for Assessing their Efficacy using Qualitative and Quantitative Parameters in detecting Primary Tumors Nodal Metastases as well as Planning Therapy and Monitoring Response

Abstract

This research is on head and neck cancer patients by 18F-FDG PET-CT imaging with respect to anatomical and metabolical tumor volumes application in various aspects of management of upper aerodigestive tract-primary and metastatic nodal disease originating from extra cranial sites. Head and Neck malignancies are the most common cancer in India, especially in males. It requires precise diagnosis, treatment, predictability of prognosis, monitoring treatment response etc., in order to provide radical treatment for good quality of life. Imaging modalities like US, CT, MRI and PET-CT have a vital role in the management of Head and Neck malignancy. It is inferred that PET-CT has a relatively stronger role in the above patients. Hence, an attempt is made to compare the metabolic volume with that of anatomic volume in extracranial head and neck malignancy patients. Their efficacy is also assessed by qualitative and quantitative parameters in detecting primary tumor, nodal metastasis, radiotherapy planning and monitoring treatment response. This study involves 154 head and neck patients of extracranial origin. They had 18F-FDG PET-CT with standard protocol wherein anatomical, metabolic tumor volume (ATV and MTV) and tumor size were measured by WHO and RECIST methods. The FDG avidity by SUVmax and qualitative visual analysis were carried out. This study is divided into 6 categories to fulfill the objective of the research. The obtained results were analyzed with suitable statistical parameters. This includes student pair t test, Cox Regression analysis, correlation efficient ratio, receiver operating characteristics curve and Kaplan Meier methods. Finally, the PET-CT has a definitive role in head and neck malignancy. Both quantitative and semi-quantitative parameters are found useful in diagnosis, planning treatment and predicting prognosis. The study also throws light that the PET-CT may alter the clinical protocols, in order to benefit the patient community, especially in head and neck cancer.