Monitoring of response to neoadjuvant therapy by positron emission tomography

Neoadjuvant therapy is frequently hampered by the lack of reliable non-invasive techniques for prediction and assessment of response. Positron emission tomography using the glucose analogue F-18-fluorodeoxyglucose (FDG-PET) provides a unique means of non-invasive assessment of tumor metabolism. Several recent studies have indicated that a reduction of tumor metabolic activity after neoadjuvant therapy is closely correlated with the degree of histopathological tumor regression. The reduction of metabolic activity may also allow one to predict subsequent response early during the course of therapy. Therefore FDG-PET may permit individualized therapy management. However, there is a requirement for larger-scale trials to assess this technique.