Merkel cell carcinoma: a case report

Abstract

Merkel cell carcinoma is a rare and aggressive cutaneous neuroendocrine malignancy that presents as a persistent red-purplish, asymptomatic and rapidly growing nodule. It typically affects sun-exposed skin of white elderly individuals. In addition, risk factors for Merkel cell carcinoma include immunosuppression, as well as the presence of multiple myeloma or a history of chronic lymphocytic leukemia. To diagnose Merkel cell carcinoma, five criteria of the AEIOU algorithm proposed in 2008 by a group of scientists at the University of Washington are used. From the methods of laboratory diagnostics a detailed analysis of blood is used, also a histological and immunohistochemical study is carried out. Among the methods of instrumental diagnostics, ultrasound examination of the primary tumor and groups of lymph nodes of the appropriate localization, abdominal and pelvic organs; chest X-ray and skeletal bone scintigraphy; positron emission tomography combined with X-ray computed tomography are mandatory. A sentinel node biopsy followed by histological and immunohistochemical examination is recommended in the absence of metastatic lymph node lesions. We herein contribute by reporting a case of Merkel cell carcinoma affecting the forearm of a 51-year-old female. This clinical case confirms the aggressiveness of this type of the skin cancer as well as high possibility of misdiagnosis due to the scarce occurrence of Merkel cell carcinoma and lack of professional knowledge. Therefore, it is important for the practitioners involved in the care of skin lesions to be aware of this condition and the need for a multidisciplinary treatment approach.