Dual Time Point PET in Lymphoma

This study aims to investigate the value of dual time point PET/CT in lymphoma. Since FDG uptake is linked to glucose metabolism, PET imaging is also used to detect suspected sites for infectious and inflammatory disorders. In a clinical setting, it is a challenge to distinguish between FDG uptake in benign and malignant lesions and this gives rise to a considerable quantity of false positive results and decreased positive predictive values. Performing FDG-PET imaging sixty minutes after injection is common practice in the staging and surveillance of lymphoma but this procedure may not be optimal, especially not in settings where benign inflammatory lesions are of clinical concern.

In an attempt to find an alternative method for this discrimination, dual time point FDG-PET was introduced. This technique has shown itself to be a potentially promising method in FDG-PET imaging for distinguishing between malignant and benign lesions using SUV values. The reason for the different FDG uptake patterns between inflammatory and malignant lesions is unclear. Several factors may contribute to this phenomenon on a cellular basis. It has been shown that cancer cells exhibit increased numbers of glucose transporter and low level of glucose-6-phosphatase. Varying levels between different cancer cell types may explain the different FDG uptake curves. Because various cell types exhibit varying rates of FDG uptake we believe that kinetic investigation may prove to be of value in understanding different types of lymphoma and identifying how to perform precise imaging for staging and surveillance.