6-[F-18]fluoro-L-DOPA positron emission tomography in the imaging of Merkel cell carcinoma: preliminary report of three cases with 2-deoxy-2-[F-18]fluoro-D-glucose positron emission tomography or pentetreotide-(111In) SPECT data

• Published in: Molecular imaging and biology Vol. 7; no. 4; pp. 257 - 261
• Main Authors: Talbot, Jean-Noël, Kerrou, Khaldoun, Missoum, Filda, Grahek, Dany, Aide, Nicolas, Lumbroso, Jean, Montravers, F
• Format: Journal Article
• Language: English
• Published: United States Springer Nature B.V 01.07.2005
• Subjects: Aged; Carcinoma, Merkel Cell - pathology; Dihydroxyphenylalanine - analogs & derivatives; Female; Fluorine Radioisotopes; Glucose-6-Phosphate - analogs & derivatives; Glucose-6-Phosphate - metabolism; Humans; Male; Middle Aged; Neoplasm Staging; Positron-Emission Tomography - methods; Positrons; Radionuclide Imaging; Receptors, Somatostatin - metabolism; Somatostatin - analogs & derivatives; Somatostatin - metabolism; Tomography, Emission-Computed, Single-Photon - methods
• ISSN: 1536-1632; 1860-2002
• DOI: 10.1007/s11307-005-0006-3

Merkel cell carcinoma (MCC) is an uncommon and aggressive cutaneous neoplasm of neuroendocrine origin. Somatostatin receptor scintigraphy (SRS) and positron emission tomography (PET) using 2-deoxy-2-[F-18]fluoro-D-glucose (FDG) have been proposed to stage MCC and to detect early recurrences. As 6-[F-18]fluoro-L-DOPA (FDOPA) is taken up by other neuroendocrine tumors, we speculated that FDOPA-PET could image MCC. FDOPA-PET was performed together with FDG-PET (three patients) and SRS (two patients) in different clinical settings: localization of the primary tumor, staging, and suspicion of recurrence. Uptake of FDOPA-(18F) by MCC was observed in the two true-positive cases, with an agreement between the results of FDOPA-PET, FDG-PET, and SRS; however, the contrast was lower on FDOPA-PET than on FDG-PET images. In the last patient suspected of recurrence repeatedly on SRS and with inconclusive FDG-PET, FDOPA-PET was negative, and a 12-month follow-up demonstrated a true-negative result. MCC takes up FDOPA-(18F). The potential role of FDOPA-PET in its management warrants clarification.