Prediction and Early Detection of Response by NMR Spectroscopy and Imaging

Pretreatment P-31 magnetic resonance (MRS) when applied to a cadre of 41 non-Hodgkin's lymphoma (NHL) regardless of disease type or stage and regardless of therapeutic regimen, was able to predict about two thirds of the patients that exhibited a complete response (CR; sensitivity 0.92, specificity 0.79). However, when the study was restricted to 27 NHL patients with the most common form of NHL, diffuse large B-cell lymphoma, all of whom were treated with RCHOP (rituximab plus CHOP chemotherapy) or RCHOP-like therapy, was able to predict CR and non-CR with a sensitivity of 1.0 and specificity of 0.90 by Fisher analysis). Patients predicted not to exhibit a CR could be directed to more vigorous therapeutic regimens followed by bone marrow transplantation or to experimental new therapeutic agents. This article highlights a general strategy for non-invasively monitoring response to inhibitors of specific signal transduction pathways by monitoring the corresponding metabolic pathway that is modified by signal transduction inhibition.