MRI and PET scans for primary staging and detection of cervical cancer recurrence

Worldwide, cervical cancer is the second most common malignancy in women, and is a major cause of morbidity and mortality. Accurate tumor staging is essential for optimal treatment planning and prognosis. Cervical cancer is staged by clinical examination according to the International Federation of Gynecology and Obstetrics staging system. However, clinical staging has inherent deficiencies in evaluating several parameters that are critical for treatment planning. It is now widely accepted that cross-sectional imaging, and in particular MRI, has an important role to play in the staging of these tumors. MRI is an excellent modality for depicting invasive cervical cancer: it can provide objective measurement of tumor size and provides a high negative predictive value for parametrial invasion and stage IVA disease. MRI and positron emission tomography (PET)/computed tomography (CT) play key roles in identifying recurrent disease. PET/CT is also useful in detecting nodal and distant metastases and in radiotherapy planning. Diffusion-weighted MRI is an emerging imaging technique that is currently being evaluated for the detection of primary and recurrent disease and in the assessment of treatment response.