Comparison of CT based and integrated f 18 FDG pet CT scan based gross tumour volume in head and neck cancers and evaluation of the different segmentation method for delineation of the target on pet scan.

Abstract

Head and neck malignancy are a major cause of morbidity and mortality throughout the world. The incidence of head and neck malignancies are very high in India and it ranks third commonest, after breast and cervical cancer. The SBR technique was superior to the fixed threshold technique using SUV 40% and SUV 50% for target volume delineation and therefore should be the method for autocontouring on PET scan. Creating metabolic tumour volume from PET alone without considering the anatomical part from the CT scan can fail in most cases to give an accurate delineation of tumour. Integrating the metabolic tumour volume obtained with autocontouring using the SBR technique on the PET scan along with anatomical part on CT which does not show uptake on the PET scan and clinical findings probably will be the best method of target volume delineation