Radionuclide imaging of hypoxia: Where are we now? Special attention to cancer of the cervix uteri

Cancer of the cervix is the fourth commonest malignancy in women worldwide and it also ranks fourth as the cause of cancer related mortality in women. Hypoxia is a common characteristic of solid tumours and cervical cancer is no exception. Hypoxia is associated with increased aggressiveness, risk of invasion and metastasis. Tumour hypoxia also results in resistance to both radiation therapy and chemotherapy leading to a poorer prognosis. In-vivo measurement of tumour hypoxia is vital in oncologic practice because it can predict outcome and identify patients with a worse prognosis. Mapping of tumour hypoxia may also help select patients that may benefit from applicable treatments. While traditional methods of measuring hypoxia such as the Eppendorf probe is considered the gold standard, it is invasive and technically demanding. Non-invasive methods of measuring tumourhypoxia are ideal. Positron emission tomography/computed tomography (PET/CT) imaging with nitro-imidazole-based tracers is a highly sensitive nuclear imaging technique that is suited for non-invasive in vivo monitoring of hypoxia. Over the years various hypoxia specific PET tracers have been investigated in various malignancies including cancer of the cervix. Several fluorine-18 (