Merkel Cell Carcinoma of the Head and Neck: A Single Institutional Experience

Hindawi Publishing Corporation Journal of Skin Cancer Volume 2013, Article ID 325086, 7 pages http://dx.doi.org/10.1155/2013/325086 Research Article Merkel Cell Carcinoma of the Head and Neck: A Single Institutional Experience G. Morand,1 D. Vital,1 T. Pézier,1 D. Holzmann,1 M. Roessle,2 A. Cozzio,3 and G. F. Huber1 1 Division of Otolaryngology, Head and Neck Surgery, University Hospital Zurich, Frauenklinikstraße 24, 8091 Zurich, Switzerland Institute of Surgical Pathology, University Hospital Zurich, Frauenklinikstraße 24, 8091 Zurich, Switzerland 3 Division of Dermatology, University Hospital Zurich, Frauenklinikstraße 24, 8091 Zurich, Switzerland 2 Correspondence should be addressed to G. Morand; Received 28 October 2012; Accepted 22 December 2012 Academic Editor: Boban M. Erovic Copyright © 2013 G. Morand et al. is is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Merkel cell carcinoma (MCC) is a rare cutaneous malignancy occurring mostly in older immunocompromized Caucasian males. A growing incidence of MCC has been reported in epidemiological studies. Treatment of MCC usually consists of surgical excision, pathological lymph node evaluation, and adjuvant radiotherapy. is paper reports the experience of a single tertiary center institution with 17 head and neck Merkel cell carcinoma patients. Median followup for the cohort was 37.5 months. Aer �ve years, recurrence-free survival, disease speci�c survival, and overall survival were 85%, 90%, and 83%, respectively. Our limited data support the use of adjuvant radiotherapy. We also report two cases of MCC located at the vestibule of the nose and two cases of spontaneous regression aer diagnostic biopsy. About 40% of our patients were referred to our center for surgical revision and pathological lymph node evaluation. Increased awareness of MCC and an interdisciplinary approach are essential in the management of MCC. 1. Introduction In 1875, Merkel, professor of anatomy at the University of Rostock, Germany, for the �rst time described “Tastzellen” (touch cells)—later known as Merkel cells—in the epidermis of domestic animals and humans [1]. In 1972, Toker �rst reported a case series of �ve patients with “trabecular carcinoma” and recognized a “distinct pathological entity,” with a “capricious clinical behaviour” [2]. It took Tang and Toker another six years to determine that trabecular carcinoma “most probably” derives from Merkel cells [3]. More recently, in 2008, a previously unknown polyomavirus was found to be integrated in Merkel cell carcinoma (MCC) [4]. Now known as Merkel Cell polyomavirus (MCV), this virus is indeed thought to be a causative agent in MCC [5, 6] and has been associated with about 80% of MCC cases [4, 7–10]. A previous study from our institution reported similar prevalence of MCV in MCC [11]. Con�icting evidence exists about the prognostic value of MCV status [7, 8, 12–14]. Important differential diagnoses of MCC are basal cell carcinoma, small cell melanoma, lymphoma, small blue round cell tumours, and especially metastatic small cell lung carcinoma [15]. A thorough histo- or cytopathological workup including immunohistochemistry (e.g., CK20, TTF1, and neuroendocrine markers) [16] combined with entire examination and clinical history usually allows to differentiate the above mentioned entities. A recent study by Smith et al. [17] drawn from an USpopulation based database (SEER) with over 4,300 MCC patients showed that 48% of all MCC are primarily located in the head and neck area (HN-MCC), with men representing about 61% of the patient population. e overwhelming majority of patients were Caucasian. Hodgson [18] reported a incidence of Merkel cell carcinoma of 0.44/100,000/year in 2001 from the same database. Interestingly, there seems to be a sharp increase in the number of cases being reported. Hodgson performed a comparative analysis and showed an 8% estimated annual percentage change (EAPC) in MCC incidence from 1986 until 2001. is change was attributed to the ageing of population and the growing prevalence of immunocompromized 2 patients, two known risk factors for MCC [18–22]. Furthermore, the authors noted that this change might also result from increased awareness and reporting of MCC [18]. A further risk factor for MCC is UVB exposure, as shown in epidemiological studies [23] and mutations analysis of TP53 [24]. Expression of p53 has been correlated to MCV-negative MCC [13, 14, 25], thus suggesting a different pathogenesis in MCV-positive and MCV-negative MCC. e authors of another epidemiological study from e Netherlands [19] reported similar incidence trends of MCC with an EAPC of 8%. For the same period, the EAPC for melanoma and squamous cell carcinoma of the skin were 4% and about 2%, respectively. e prognosis of MCC remains poor, with a 5-year relative survival for local, regional, and metastatic disease of about 75%, 50%, and 20%, respectively [19]. Smith et al. reported a 5-year disease speci�c survival for pN0, pN1, and M1 in HN-MCC patients of 83.3%, 58.3%, and 31.3%, respectively [17]. Epidemiological analyses have established several prognostic factors in HN-MCC [17]: male sex, >T2primaries, N-positive, M-positive, and tumour location at the lip were shown to be independent negative risk factors. Unlike for nonhead and neck-MCC (NHN-MCC), increasing tumour size was not a prognostic factor for HN-MCC [17]. Lemos et al. have shown the critical impact of pathological lymph node evaluation for MCC patients [26]. For example, in the management of cutaneous melanoma, sentinel lymph node biopsy (SLNB) is now a standard of care [27]. Analogically, SLNB has gained popularity in the past years in the management of MCC, currently being recommended as standard treatment [28], independently of the size of the primary tumour [29–32], as SLNB permits a pathological lymph node evaluation with less morbidity compared to elective neck dissection [33, 34]. SLNB studies have shown that about 30% of cN0 MCC patients harbour occult metastasis [35, 36], with up to 20% false negative rate [37, 38]. Prophylactic irradiation is usually accepted as an alternative in the management of the clinically negative neck [39]. e superiority of adjuvant radiotherapy in local and regional control has been shown in a meta-analysis of observational studies [40]. A recent multicentric prospective randomized controlled trial conducted in France again showed improved locoregional control [41]. Both studies could not prove a signi�cant advantage of adjuvant radiotherapy on disease speci�c survival. For inoperable patients, an in-�eld control rate of 75% has been reported with radiotherapy alone, with 55 Gy as a minimum dose for macroscopic disease [42]. Other studies also show acceptable results for radiotherapy alone [43, 44]. e aim of this (...truncated)