BETTER VISUALIZATION OF RETINOBLASTOMA METASTASES WITH TC-99M SESTAMIBI VERSUS TI-201

Tc-99m sestamibi has been shown to accumulate in several primary malig nant tumors, but data regarding its use In the detection of distant me tastases are limited, Despite its physical limitations, TI-201 now has a definite place in the routine evaluation of certain primary and met astatic tumors, This report describes the value of Tc-99m sestamibi an d its superiority to TI-201 in the visualization of distant metastases in a 2-year-old girl with bilateral retinoblastoma. Three sites of so ft tissue and bone metastasis were demonstrated by Tc-99m sestamibi im aging, Of these metastases, the one in the parieto-occipital region sh owed evident TI-201 uptake, while the other two In the right arm and c hest wall showed only slightly increased uptake, which could hardly be spotted without the confirmation of a later Tc-99m sestamibi scan, Th e scintigraphic findings were confirmed with histopathologic examinati on. Tc-99m sestamibi scan is effective and superior to TI-201 in the d etection of distant soft tissue and bone metastases from retinoblastom a.