Somatostatin receptor positron emission tomography/computed tomography imaging in Merkel cell carcinoma. (7th October 2015)

• Record Type: Journal Article
• Authors: Sollini, M.; Taralli, S.; Milella, M.; Erba, P.A.; Rubagotti, S.; Fraternali, A.; Roncali, M.; Moscarella, E.; Perotti, G.; Rufini, V.; Versari, A.
• Is Part Of: Journal of the European Academy of Dermatology and Venereology. Volume 30:Number 9(2016:Sep.)
• Page Start: 1507
• Page End: 1511
• Publication Date: 2015-10-07
• Subjects: Dermatology -- Periodicals; Sexually transmitted diseases -- Periodicals; 616.5
• DOI: 10.1111/jdv.13405
• Languages: English
• ISSNs: 0926-9959

Abstract

Abstract: Background: Merkel cell carcinoma (MCC) is an uncommon aggressive primary cutaneous carcinoma with neuroendocrine differentiation. However, literature data about the use of somatostatin receptor positron emission tomography/computed tomography (PET/CT) imaging in MCC are limited and its role is not clearly stated. Objective: To investigate the role of PET/CT using somatostatin analogues radiolabelled with gallium‐68 in patients with MCC. Methods: All patients affected by MCC who performed a somatostatin receptor PET/CT imaging from October 2007 to May 2014 were retrospectively analysed. The diagnostic performances of PET/CT were evaluated on a patient‐based analysis and compared to final diagnosis (histology = 3 or clinical/radiological follow‐up = 20). Results: We evaluated 23 consecutive MCC patients [18 men; median age 71 years (range 47–87)]. Primary tumour was located in ear (1/23), cheek (3/23), arm (2/23), hand (1/23), back (1/23), anal canal (1/23), gluteus (4/23), thigh (3/23) and popliteal fossa (1/23). In 6/23 patients, the site of primary tumour was unknown. PET/CT was performed to detect primary tumour site (4/23) or to stage (8/23) or re‐stage (11/23) patients. PET/CT resulted positive in 14/23 patients and according to the final diagnosis was defined true positive, true negative, false positive (FP) and false negative in 11/23, 8/23, 3/23 and 1/23 cases respectively. FP PET/CT results were due to unspecific liver uptake, post‐surgical inflammation and pancreatic neuroendocrine tumour. PET/CT was unable to detect primary tumour site in all patients with unknown primary MCC. Sensitivity, specificity and diagnostic accuracy of PET/CT were 92%, 73% and 83% respectively. Conclusions: In our experience, somatostatin receptor PET/CT imaging resulted useful in patients with MCC and presented high diagnostic performances with a significant impact in disease management although in patients with unknown primary MCC, it was unable to identify the primary tumour site.