%0 Journal Article
%T Extensive central nervous system involvement in Merkel cell carcinoma: a case report and review of the literature
%A Kasim Abul-Kasim
%A Kristina S£żderstr£żm
%A Lennart Hallsten
%J Journal of Medical Case Reports
%D 2011
%I BioMed Central
%R 10.1186/1752-1947-5-35
%X A 65-year-old Caucasian man presented with a sudden onset of severe headache and a three-month history of balance disturbance. Magnetic resonance imaging revealed a large meningeal metastasis. The radiologic workup showed retroperitoneal and inguinal lymph node metastases. Biopsy of the inguinal lymph nodes showed metastases of Merkel cell carcinoma. Biopsy from three different suspected skin lesions revealed no Merkel cell carcinoma, and the primary site of Merkel cell carcinoma remained unknown. Leptomeningeal metastases, new axillary lymph node metastases, and intraspinal (epidural and intradural) metastases were detected within six, seven and eight months, respectively, from the start of symptoms despite treating the intracranial metastasis with gamma knife and the abdominal metastases with surgical dissection and external radiotherapy. This indicates the aggressive nature of the disease.To the best of our knowledge, this is the first report in the literature of an intracranial meningeal metastasis of Merkel cell carcinoma treated with gamma knife and of intraspinal intradural metastases of Merkel cell carcinoma. Despite good initial response to radiotherapy, recurrence and occurrence of new metastases are common in Merkel cell carcinoma.Merkel cell carcinoma (MCC) is a rare malignant neoplasm of the skin that is locally invasive and frequently metastasizes to lymph nodes, liver, lungs, bone and brain [1]. The tumor was first described by Toker in 1972 [2] as a trabecular cell carcinoma. The fact that MCC is now considered a neuroendocrine tumor is supported by the presence of calcitonin and neuron-specific enolase within the tumor [1]. The diagnosis of MCC is based on the clinical findings of aggressive cutaneous tumors and the histopathologic examination of specimens using light and electron microscopy with a defined panel of immunoperoxidase stains [3]. Hodgson [4] reported that the incidence of MCC has increased threefold between 1986 and 2001 (the rate of M
%U http://www.jmedicalcasereports.com/content/5/1/35