Fused radioimmunoscintigraphy for treatment planning

Advances in imaging technologies, including computerized tomography (CT) and single-photon emission tomography (SPECT), are improving the role of imaging in prostate cancer diagnosis and treatment. Hybrid (SPECT/CT) imaging, in particular, shows an increased sensitivity for identification of prostate cancer. Published studies have also recently proposed a new paradigm in the administration of radiation therapy for prostate cancer, favoring dose-escalation strategies to improve tumor control for localized disease. Conventional dose-escalation protocols have previously relied primarily on margin extension to the entire prostate gland to achieve dose-escalation; extending increased risk to radiosensitive normal structures. A newer strategy proposes use of advanced imaging to confine dose-escalation to biological target volumes identified on capromab pendetide SPECT/CT -fused image sets or image-guided radiation therapy (IGRT). This strategy defines a shift in radiation dosimetry and planning from uniform glandular prescription dosing with dose-escalation applied generically to the peripheral regions and margin extension; to dose-escalation confinement to discrete regions of known disease as defined by focal uptake on radioimmunoscintigraphy fusion with anatomic image sets, with minimal margin extension. The introduction of advanced imaging for IGRT in prostate cancer has also introduced an improved capability for the early-identification of patients at risk for metastatic disease, where more aggressive therapeutic interventions may prove beneficial.