CT-PET guided target delineation in head and neck cancer and implications for improved outcome

摘要: Aim: Fifty percent of patients with squamous cell carcinoma the Head and Neck develop loco-regional recurrence after treatment. Factors leading to this failure are most likely altered intra-tumoural glucose metabolism increased hypoxia. Tissue utilisation degree hypoxia can be visualised by CTPET imaging 18FDG hypoxic radio-nuclides. This thesis has investigated CT-PET guided target volume delineation methods attempted validate 64Cu-ATSM as a radio-nuclide in patients Neck. Materials Methods: Eight locally advanced disease underwent imaging before during curative radiotherapy or chemo-radiotherapy. Fixed (SUV cut off percentage threshold SUVmax) adaptive thresholds were investigated. The functional volumes automatically delineated these methods and SUVmax were compared at each point, between thresholds. Four disease, two seven days prior surgery, underwent 3D dynamic imaging immediately injection 64Cu- ATSM. Two also imaged 18 hours injection, two underwent contrast-enhanced CT evaluate perfusion. All received pimonidazole before surgery. pimonidazole, GLUT1, CAIX, HIF1a immuno-histochemical fractions defined. Staining was correlated retention pattern 3 time points. Hypoxic according tumour muscle, blood background ratios. Results: 18FDG primary lymph node significantly reduced with radiation dose SUV cut off method reduction in the within volume. Volume found between thresholds same delineation method. other methods not (except functional volume when defined threshold). 64Cu-ATSM staining but with blood flow. Tumour ratios time which influenced the volume. Conclusion: Dose-escalated image-guided strategies using guided functional have potential improve control Neck. CT-PET is intricately linked and threshold timing imaging. 64Cu-ATSM promising warrants further investigation.