The biological behavior and prognosis of
gliomas depend largely on cellular proliferation, resistance to
chemotherapy, and metastatic potential. Proliferative propensity has significant implications on patient management but its assessment requires tissue sampling; the non-invasive estimation of
brain tumor proliferation represents therefore a major goal. Pentavalent
technetium-99 m dimercapto-
succinic acid [99m Tc-(V)
DMSA] is a
tumor-seeking radiotracer displaying affinity for
gliomas; its intracellular accumulation is directly linked to cell proliferation. We performed a tomographic 99m Tc-(V)
DMSA brain scan in a 35-year-old male baring a recurrent
glioblastoma multiforme, to depict its proliferative disposition. The patient had been diagnosed 14 months earlier and had been submitted to surgery, followed by
adjuvant radiotherapy and
temozolomide-based
chemotherapy. On clinical suspicion of recurrence 5 months later, magnetic resonance imaging (MRI) revealed a lesion at the site of preceded surgery, which was treated by
imatinib mesylate. No improvement was ascertained the following months and radiographic assessment verified
tumor progression. Scintitomography revealed avid radiotracer uptake in the entirety of the lesion (the distribution of radioactivity closely conforming to the morphological
tumor boundaries), an indication that the
neoplasm demonstrated no substantial proliferation decline in response to
imatinib. The patient deceased a few weeks later. Mounting in vivo and in vitro evidence indicates that 99m Tc-(V)
DMSA is a credible non-invasive proliferation depicter, its cellular accumulation linked closely to
phosphate uptake and
kinase pathway activation. A potential role in patient management, prognosis estimation, and
therapy response monitoring could occur for this tracer.