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Management of Non-melanoma Skin Cancers: Merkel Cell Carcinoma

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Melanoma

Abstract

Merkel cell carcinoma is a rare primary cutaneous carcinoma of the skin, which shows high aggressiveness, high risk of locoregional and distant spread, a mortality rate considerably higher than that of cutaneous melanoma, and a poor survival. Its incidence has increased during the past 20 years. The studies published from 2008 have introduced interesting changes in the understanding of its epidemiology, pathogenesis and consequently in the diagnostic codes and the therapeutic options. These advancements in our understanding of Merkel cell carcinoma have contributed to better defining the high-risk patients, which may require a more comprehensive approach to treatment. A multidisciplinary team approach to the overall management is crucial for the optimal treatment of patients with Merkel cell carcinoma. Surgery and radiotherapy play a fundamental role in the management of this tumor, with both associated with improved locoregional control and disease-free survival. The risk for systemic recurrence is quite high, with no truly validated prognostic factors to identify those patients who will experience a distant failure. For those that develop metastatic disease, adjuvant chemotherapy can be utilized with little benefit toward a longer survival. Newer treatment options examining the role of immunotherapy have shown great promise in ongoing clinical trials and will likely replace chemotherapy as the preferred treatment option for stage 4 Merkel cell carcinoma in the future.

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Abbreviations

CLND:

Complete lymph node dissection

CRT:

Chemoradiotherapy

CTR:

Clinical trials

DFS:

Disease-free survival

H&N:

Head and neck

IT:

Immunotherapy

LTAg:

Large tumor antigen

MCC:

Merkel cell carcinoma

MCV:

Merkel cell polyomavirus

NAFT:

Nuclear factor of activated T cells

NK:

Natural killer

OS:

Overall survival

PD-1:

Death protein-1

PD-L1:

PD-1 ligand

RT:

Radiation therapy

SEER:

Surveillance, Epidemiology, and End Results

SLNB:

Sentinel lymphatic node biopsy

sTAg:

Small tumor antigen

UV:

Ultraviolet light

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Correspondence to Isabel Prieto M.D., Ph.D. .

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Prieto, I. et al. (2018). Management of Non-melanoma Skin Cancers: Merkel Cell Carcinoma. In: Riker, A. (eds) Melanoma. Springer, Cham. https://doi.org/10.1007/978-3-319-78310-9_39

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