The impetus for undertaking this study is that we are searching for imaging methods that could potentially serve as surrogate indicators of pathological response. One such modality that we wish to investigate as it may be ultimately useful in this patient population is diffuse optical spectrometry. This modality depends on differentiating oxygenated from deoxygenated tissue but is also sensitive to other changes in tissue characteristics. It has been used before in proof-of-principle studies differentiating benign from malignant disease but we hypothesize that it may be more useful in terms of monitoring tumour responses to treatment. This is a non-invasive imaging modality that is easy to administer and relatively inexpensive.