ABSTRACT
Abstract Merkel cell carcinoma is a rare skin cancer with neuroendocrine differentiation. The risk factors include sun exposure, advanced age, immunosuppression (such as transplant recipients, patients with lymphoproliferative neoplasms, or patients with HIV), and Merkel cell polyomavirus infection. Clinically, Merkel cell carcinoma appears as a cutaneous or subcutaneous plaque or nodule, but this tumor diagnosis is rarely made clinically. Therefore, histopathology and immunohistochemistry are usually necessary. Primary tumors without evidence of metastases are treated with complete surgical excision and appropriate surgical margins. The presence of occult metastasis in a lymph node is frequent and a sentinel lymph node biopsy should be performed. Postoperative adjuvant radiotherapy increases local tumor control. Recently, agents that block the PD-1/PD-L1 pathway have shown objective and durable tumor regression in patients with advanced solid malignancies. The first anti-PD-L1 antibody used in patients with Merkel cell carcinoma was avelumab, but pembrolizumab and nivolumab have also shown efficacy. This article describes the current state of knowledge of the epidemiology, diagnosis, and staging of Merkel cell carcinoma, as well as new strategies for its systemic treatment.
ABSTRACT
Abstract Background: Human Polyomaviruses such as MCPyV and HPyV6 are frequently found as part of healthy skin microbiota and have been associated with Merkel cell carcinoma (MCC), pruritic and dyskeratotic dermatoses, respectively. Their presence in other types of skin conditions varies greatly depending on lesion type and population. Objectives: To analyse comparatively the presence of MCPyV and HPyV6 in nonmelanoma skin cancers and healthy skin. Methods: The authors utilized qPCR techniques to quantify these pathogens in NMSC, premalignant diseases, and healthy skin of 87 patients. Results: MCPyV was detected in over 40% of samples, while HPyV6 was in 9.6%. MCPyV load was higher in squamous cell carcinomas (SCC) compared to basal cell carcinomas (BCC) (p = 0.016) and HPyV6 showed a higher percentage of infected cells in areas of low solar exposure as well as normal skin (p = 0.012). A fair agreement (kappa = 0.301) was found between MCPyV detection in lesions and their respective perilesional skin, indicating a random process of local dissemination of the virus. Study limitations: The lack of a larger sampling of different lesion types and protein expression analyses limits the correlation findings. Conclusions: This is the first report of HPyV6 detection in the healthy skin of a Brazilian population, but the role of both polyomaviruses in NMSC has yet to be demonstrated.
ABSTRACT
Abstract Viruses have been frequently identified in several human neoplasms, but the etiological role of these viruses in some tumors is still a matter of controversy. Polyomaviruses stand out among the main viruses with oncogenic capacity, specifically the Merkel cell polyomavirus (MCPyV). Recent revisions in the taxonomy of polyomaviruses have divided the Polyomaviridae family into six genera, including 117 species, with a total of 14 currently known human-infecting species. Although the oncogenicity of polyomaviruses has been widely reported in the literature since 1950, the first description of a polyomavirus as an etiological agent of a neoplasm in humans was made only in 2008 with the description of MCPyV, present in approximately 80% of cases of Merkel cell carcinoma (MCC), with the integration of its genome to that of the tumor cells and tumor-specific mutations, and it is considered the etiological agent of this neoplasm since then. MCPyV has also been detected in keratinocyte carcinomas, such as basal cell carcinoma and squamous cell carcinoma of the skin in individuals with and without immunosuppression. Data on the occurrence of oncogenic viruses potentially involved in oncogenesis, which cause persistence and tissue injury, related to the Merkel cell polyomavirus are still scarce, and the hypothesis that the Merkel cell polyomavirus may play a relevant role in the genesis of other cutaneous carcinomas in addition to MCC remains debatable. Therefore, the present study proposes to explore the current knowledge about the presence of MCPyV in keratinocyte carcinomas.
ABSTRACT
Carcinoma de células de Merkel é um tumor neuroendócrino raro e agressivo de pele que usualmente apresenta-se como lesão única na região de cabeça ou pescoço. Relata-se um caso de topografia e apresentação atípicas, com presença de múltiplos e simultâneos tumores na perna esquerda de rápida evolução, associados à linfonodomegalia inguinal palpável, com diagnóstico confirmado por meio de histopatologia e imuno-histoquímica. Realizada exérese de linfonodo inguinal esquerdo e das lesões cutâneas com margem de segurança
Merkel cell carcinoma is a rare and aggressive neuroendocrine skin tumor usually presenting as a single lesion in the head or neck region. We report a case of atypical topography and presentation, with multiple and simultaneous tumors on the left leg of rapid progression associated with palpable inguinal lymphadenopathy and diagnostic confirmation by histopathology and immunohistochemistry. Exeresis of the left inguinal lymph node and skin lesions with a safety margin was performed
ABSTRACT
Abstract Merkel cell carcinoma is an uncommon neuroendocrine carcinoma with a rising incidence and an aggressive behavior. It predominantly occurs in older patients, with onset occurring at a mean age of 75-80 years. Recognized risk factors are ultraviolet sunlight exposure, immunosuppression, and, more recently, Merkel cell polyomavirus. We report a case of Merkel cell carcinoma in a young HIV positive patient with Merkel Cell polyomavirus detected in the tumor.
Subject(s)
Humans , Male , Middle Aged , Skin Neoplasms/diagnosis , Tumor Virus Infections/diagnosis , Carcinoma, Merkel Cell/diagnosis , AIDS-Related Opportunistic Infections/diagnosis , Polyomavirus Infections/diagnosis , Merkel cell polyomavirus , Skin Neoplasms/virology , Carcinoma, Merkel Cell/virology , Immunocompromised Host , AIDS-Related Opportunistic Infections/virologyABSTRACT
O carcinoma de células de Merkel (CCM) é um tumor raro de origem neuroendócrina e epidérmica, de mau prognóstico. Está classicamente associado à imunossupressão, exposição solar e, mais recentemente, ao poliomavírus (MCPyV). Caracteristicamente, o carcinoma de células de Merkel apresenta positividade para marcadores epiteliais e neuroendócrinos. A expressão combinada desses marcadores é o dado que corrobora o diagnóstico. Tumores MCPyV- possuem prognóstico desfavorável. Relata-se um caso de carcinoma de células de Merkel com imunofenótipo atípico (CK20 negativo) e comportamento agressivo. Este relato se justifica para reforçar a importância do conhecimento, pelos dermatologistas, de diferentes imunofenótipos que podem estar associados ao carcinoma de células de Merkel.
The Merkel cell carcinoma is a rare tumor of neuroendocrine and epidermal origin and with poor prognosis. It is classically associated with immunosuppression, exposure to the sunlight and, more recently, with the polyomavirus. It is positive for epithelial and neuroendocrine markers. The combined expression of these markers confirms the diagnosis. Polyomavirus tumors have an unfavorable prognosis. The authors report a case of Merkel cell carcinoma with atypical immunophenotype (CK20 negative) and aggressive behavior. The present report is aimed at highlighting the importance of dermatologists having knowledge of different immunophenotypes that may be associated with the Merkel cell carcinoma.
ABSTRACT
Merkel cell carcinoma (MCC) is a rare neuroendocrine tumor that is highly aggressive in nature and indolent in progression. The common risk factors for MCC are senility, prolonged exposure to sunlight, and immune deficient states. Moreover, Merkel cell polyomavirus has recently been characterized to be significantly associated with pathogenesis of MCC, including the expression of Cytokeratin 20 (CK20). Diagnosis is often difficult since histopathological results require a number of differential diagnoses through immunohistochemical (IHC) stains with other cutaneous malignancies. A 67-year-old man presented with a solitary domeshaped erythematous round mass on the left upper arm for 2 months. Biopsy and IHC studies revealed findings consistent with Merkel Cell Carcinoma of neuroendocrine origin. Common IHC stains usually confirm positive findings for CK20, which is also recognized as the key component in making the diagnosis. We present a CK20 negative MCC in light of expanding the knowledge of unusually stained IHC results in MCC.
Subject(s)
Aged , Humans , Arm , Biopsy , Carcinoma, Merkel Cell , Coloring Agents , Diagnosis , Diagnosis, Differential , Keratin-20 , Keratins , Merkel cell polyomavirus , Neuroendocrine Tumors , Risk Factors , SunlightABSTRACT
Merkel cell carcinoma (MCC) is a rare neuroendocrine tumor that is highly aggressive in nature and indolent in progression. The common risk factors for MCC are senility, prolonged exposure to sunlight, and immune deficient states. Moreover, Merkel cell polyomavirus has recently been characterized to be significantly associated with pathogenesis of MCC, including the expression of Cytokeratin 20 (CK20). Diagnosis is often difficult since histopathological results require a number of differential diagnoses through immunohistochemical (IHC) stains with other cutaneous malignancies. A 67-year-old man presented with a solitary domeshaped erythematous round mass on the left upper arm for 2 months. Biopsy and IHC studies revealed findings consistent with Merkel Cell Carcinoma of neuroendocrine origin. Common IHC stains usually confirm positive findings for CK20, which is also recognized as the key component in making the diagnosis. We present a CK20 negative MCC in light of expanding the knowledge of unusually stained IHC results in MCC.
Subject(s)
Aged , Humans , Arm , Biopsy , Carcinoma, Merkel Cell , Coloring Agents , Diagnosis , Diagnosis, Differential , Keratin-20 , Keratins , Merkel cell polyomavirus , Neuroendocrine Tumors , Risk Factors , SunlightABSTRACT
BACKGROUND: Merkel cell carcinoma (MCC) is an increasingly common neuroendocrine cancer of the skin. Merkel cell polyomavirus (MCPyV) is one of the causative agents of MCC. The prevalence of MCPyV in primary MCC and sun-exposed non-MCC tumors has been known to have different results depending on where it was investigated. OBJECTIVE: This study assesses the prevalence of MCPyV from primary MCC and sun-exposed non-MCC tumors in Korea. METHODS: A molecular pathology study was performed on 7 tissue specimens of MCC, 1 tissue specimen of metastatic small cell carcinoma of the lung, and 32 tissue specimens of non-MCC tumors occurring from sun-exposed areas [8 basal cell carcinomas (BCCs), 8 squamous cell carcinomas (SCCs), 8 actinic keratoses (AKs), and 8 seborrheic keratoses (SKs)]. All specimens were analyzed to determine the presence of MCPyV-DNA using both polymerase chain reaction (PCR) and real-time quantitative PCR. Immunohistochemistry with monoclonal antibody of MCPyV large T antigen (CM2B4) was also conducted. RESULTS: Using both PCR, MCPyV sequences were detected in six of seven MCC tissue specimens (85.7%). Five (71%) of seven MCC tumors were immunoreactive for CM2B4. All five immunoreactive cases were positive for MCPyV. However, there was no association of MCPyV with BCC, SCC, AK, and SK. CONCLUSION: Our results implicate that MCPyV may contribute to the pathogenesis of primary MCC, not of non-MCC skin tumors in Korea, and the persons with MCPyV infection are unusual in Korea compared to other areas.