We illustrate the color Doppler sonographic findings in primary cutaneous Merkel cell carcinoma. Eight cases (4 female and 4 male; mean age, 75.4 years) were collected. The most common affected regions were the face (63%) and the hip/buttock (25%). The mean transverse diameter and thickness were 21 and 14 mm, respectively. Fifty percent were oval, and 50% were dome shaped. All lesions were hypoechoic, with variable degrees of heterogeneity. All but 2 lesions were poorly defined. An acoustic reinforcement artifact was present in 3 and epidermal thickening in 2. All tumors had prominent and chaotic hypervascularity with arterial vessels (mean peak velocity, 11 cm/s; mean resistive index, 0.57).Key Words-dermatologic ultrasound; Merkel cell carcinoma; neuroendocrine tumors; oncology; skin ultrasound; soft tissue masses; superficial structures F irst described in 1972, Merkel cell carcinoma is a relatively rare cutaneous tumor of neuroendocrine origin. Most patients are older than 50 years, with a mean age at diagnosis of around 70 years, and there is a moderate prevalence of male patients. 1-5 Merkel cell carcinoma has been reported as more common in patients with light-skin, under immunosuppression status and/or with history of malignancies. 2,[6][7][8] The number of Merkel cell carcinoma cases is rising, probably because of a growing elderly population and the more frequent use of immunosuppressive therapies. 9 Additionally, Merkel cell carcinoma frequently had an aggressive behavior, with a high incidence of local recurrence as well as nodal and distant metastatic disease. The 5-year survival rates are 64% for local disease, 39% for regional nodal involvement, and 18% for distant metastatic disease. 10 Consequently, early diagnosis and prompt assessment of the locoregional extent are of paramount importance to improve patient survival. 11 Merkel cell carcinoma tends to be overlooked in the early stage. 12 Sonography is being used with increasing frequency in the assessment of skin tumors. [13][14][15][16] It supports the clinical diagnosis and provides information on the exact tumor location, extension, vascularization, and deeper tissue involvement. These data are useful for the surgeon to obtain the best oncologic as well as cosmetic results.
Materials and MethodsWe performed a multicenter collection of histopathologically proven cases of primary cutaneous Merkel cell carcinoma provided by members of the DERMUS (dermatologic ultrasound) international group.