FDG-PET in Cervical Cancer - Translational Studies

Abstract: Cervical cancer is the second most common cancer in females. The treatment, based on clinical FIGO stage, carries a significant risk of side effects. FDG-PET enables non-invasive studies of glucose metabolism. Cancer cells show an increased glucose uptake and metabolism that can be visualised and further analysed. The aims of this thesis were to evaluate FDG-PET in the clinical management of cervical cancer and to experimentally investigate the metabolic changes in a tumour following cytotoxic treatment. In a prospective study we found that FDG-PET provided important information about the extent of the disease in primary staging of locally advanced cases and in re-staging of recurrent disease. The treatment plans were altered as a result of the FDG-PET findings for one fourth of the patients. Surveillance FDG-PET 6 months after surgery for early-stage disease showed no clinical value. With a predictive FDG-PET early during radiotherapy for locally advanced disease we could identify a group of patients with an excellent prognosis. However, for the majority of the patients early prediction of outcome was not possible. Persisting hypermetabolism on FDG-PET 3 months after completed radiotherapy was associated with relapse. Experimentally, we found a transient metabolic flare in xenografted tumours on day 1 following cisplatin exposure. A metabolic flare in squamous cell carcinoma cells in vitro was found to be an early sign of response to cisplatin treatment. No increase in metabolism was detected in fibroblasts in vitro or in reactive cells in vivo. In conclusion, we have demonstrated a clinical value of FDG-PET in the management of cervical cancer, and in an experimental setting we have increased the understanding of tumour metabolism.