The Role of Positron Emission Tomography/ Computed Tomography (PET/CT) in assessment of therapeutic response in Non-Hodgkin lymphoma

Abstract

ymphoid neoplasms are broadly divided into Hodgkin disease (HD) and non-Hodgkin’s lymphoma (NHL). Non-Hodgkin lymphoma accounts for about 5% of all cases of cancer with greater tendency to extend to extra-nodal sites. Aggressive NHL usually detected by nodal and or extra-nodal involvement and although it is an aggressive lymphoma, many cases show complete remission explained that it is a chemo-sensitive tumor. Most radiologic procedures map the anatomy and morphology of tumors with little or no information about their metabolism. In recent years, imaging with positron emission tomography (PET) for tumor staging and therapy control has been introduced. Rather than anatomical information, it provides physiologic information on glucose uptake and metabolism. The main limitation of PET in tumor imaging is mainly complete absence of anatomical landmarks, which is obscured the localization of lesions. The major advantage of PET/CT is that both metabolic and anatomic information for the same body region, which are obtained at the same time. The PET and CT devices are physically aligned and the PET/CT viewer software allows close correlation of the images.