Melanocytes and dopaminergic neurons share the same ectodermal origin and can both produce melanin. Indeed, in vivo studies have shown that the radiopharmaceutical iodine-123-iodobenzamide (I-123 IBZM), which binds in vivo to dopamine D2/3 receptors, is also able to detect melanoma, and particularly melanotic melanoma. We report a case of intense IBZM uptake in nodular melanoma of the skin on the scalp. The presence of unexpected focal IBZM uptake of the skin justified histologic examination, which revealed nodular melanoma. Melanoma should be considered when one is confronted with atypical focal uptake of benzamide derivatives like IBZM, in or outside the brain.
From the Departments of *Nuclear Medicine and †Psychiatry, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands; ‡Ipse de Bruggen, Center for People with Intellectual Disability, Zwammerdam, The Netherlands; and §Department of Pathology, Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands.
Received for publication June 9, 2010; revision accepted June 28, 2010.
Department of Nuclear Medicine Academic Medical Center, University of Amsterdam, Amsterdam, The Netherlands is the Institution where this study was performed.
Reprints: Jan Booij, MD, PhD, Department of Nuclear Medicine, Academic Medical Center, University of Amsterdam, Meibergdreef 9, 1105 AZ Amsterdam, The Netherlands. E-mail: email@example.com.