LAUSR

than those without a pCR (63.8% versus 33.5%; P < 0.001). Applying an exploratory cut-off value of a 40% reduction in SULmax yielded an 86% level of sensitivity and a specificity of 55%. Most notably, this threshold also provides a high negative predictive value (88%). “These data suggest that patients who do not have a substantial reduction in SULmax by day 15 are unlikely to have a pCR to targeted therapies alone,” Connolly summarizes. This finding suggests that the majority of patients with an initial response to targeted therapy could be safely spared chemotherapy and the associated risk of adverse events. Furthermore, because these changes occur early in the course of treatment, patients who do not have a substantial reduction in SULmax could potentially be assigned to other therapies. Further clinical validation of this biomarker is necessary and eagerly awaited.