title: Merkel cell carcinoma of unknown primary site; case presentation and review of the literature.
abstract: Merkel cell carcinoma (MCC) is a rare skin malignancy associated with sun exposure and considered as a Neuroendocrine Tumor due to its characteristic histologic features. However there is increasing number of reports of Unknown Primary MCC's (UPMCC). Although initially UPMCC was considered a variant of known primary MCC, there is growing evidence that it could represent a different clinical entity. We present the case of a 60 year-old male patient who was referred to our department for surgical management of lymph node disease for UPMCC. The patient had undergone excisional biopsy of an inguinal lump, which was found to be an infiltrated lymph node by MCC. The patient underwent full imaging staging including a PET/CT, which failed to identify a primary site, and revealed only intra-abdominal lymph node disease. The patient underwent extended retroperitoneal and inguinal lymph node dissection and remains free of recurrence 16 months postoperatively.
authors.affiliation: 2nd Department of Surgery, Aretaieio Hospital, University of Athens, School of Medicine, Athens, Greece.
authors.forename: Elissaios
authors.initials: E
authors.lastname: Kontis
authors.affiliation: 2nd Department of Surgery, Aretaieio Hospital, University of Athens, School of Medicine, Athens, Greece.
authors.forename: Antonios
authors.initials: A
authors.lastname: Vezakis
authors.affiliation: 2nd Department of Surgery, Aretaieio Hospital, University of Athens, School of Medicine, Athens, Greece.
authors.forename: Eirini
authors.initials: E
authors.lastname: Pantiora
authors.affiliation: Department of Pathology, Aretaieio Hospital, University of Athens, School of Medicine, Athens, Greece.
authors.forename: Sotiria
authors.initials: S
authors.lastname: Stasinopoulou
authors.affiliation: 2nd Department of Surgery, Aretaieio Hospital, University of Athens, School of Medicine, Athens, Greece.
authors.forename: Andreas
authors.initials: A
authors.lastname: Polydorou
authors.affiliation: 2nd Department of Surgery, Aretaieio Hospital, University of Athens, School of Medicine, Athens, Greece.
authors.forename: Dionysios
authors.initials: D
authors.lastname: Voros
authors.affiliation: 2nd Department of Surgery, Aretaieio Hospital, University of Athens, School of Medicine, Athens, Greece.
authors.forename: Georgios P
authors.initials: GP
authors.lastname: Fragulidis
keywords: AJCC, American Joint Committee on Cancer; HPF, high, power field; Lymphadenopathy; MCC, Merkel cell carcinoma; Merkel cell; NET, neuroendocrine tumor; PET/CT, positron emission tomography/computed tomography; SUV, standardized uptake value; Surgical management; UPMCC, unknown primary Merkel cell carcinoma; Unknown primary site