Merkel Cell Carcinoma
Dongyou Liu in Tumors and Cancers, 2017
Merkel cell carcinoma (MCC) is an aggressive neuroendocrine cancer that is associated with the Merkel cell polyomavirus. MCC gets its name because it has ultrastructural features similar to normal Merkel cells present in the skin that are involved in mediating the sensation of fine touch. Diagnosis of MCC typically requires biopsy because MCC tumors often have a non-specific, minimally concerning appearance. MCC cells can express both neuroendocrine and epithelial proteins, and proliferation markers are frequently seen. Pathological detection/confirmation of nodal disease may be via sentinel lymph node biopsy, lymphadenectomy, or fine needle biopsy; and pathological confirmation of metastatic disease may be via biopsy of the suspected metastasis. Surgical excision with adjuvant radiotherapy has been associated with better survival and fewer recurrences than excision alone, and is often recommended except for very low-risk cases. Immunotherapeutic approaches are also showing exciting early success in MCC. Like other virus-associated cancers, MCPyV-positive MCC is highly immunologically responsive due to viral antigens expressed by tumor cells.
Non-Melanoma Skin Cancer
Pat Price, Karol Sikora in Treatment of Cancer, 2020
This chapter discusses the common non-melanoma skin cancers (NMSCs), basal cell carcinoma and squamous cell carcinoma (SCC), and explains some of the rarer tumors, including primary cutaneous lymphoma; Merkel cell carcinoma, extra-mammary Paget’s disease, and Langerhans cell histiocytosis. A mild clinical phenotype, XP variant, is recognized, which can be missed clinically but is usually associated with early onset of NMSC and marked photodamage. The risk of post-transplant skin SCC is related to the degree of immunosuppression. The long-term effects of radiation can be significant, with skin and soft-tissue atrophy and telangiectasia as well as induction of malignancy. The development of pre-malignant and malignant skin tumors will depend on the complementation group and the level of ultraviolet exposure that the patient is subjected to. High-energy pulsed carbon dioxide lasers have been used extensively to resurface wrinkled and photo-damaged skin with a low-risk of scarring.
Cutaneous Infiltrates: Non-Lymphoid
Omar P. Sangueza, Sara Moradi Tuchayi, Parisa Mansoori, Saleha A. Aldawsari, Amir Al-Dabagh, Amany A. Fathaddin, Steven R. Feldman in Dermatopathology Primer of Cutaneous Tumors, 2015
Mastocytosis comprises a spectrum of related diseases in which there is an increase in mast cells in one or more organs. It is classified into cutaneous and systemic. Cutaneous mastocytosis includes: urticaria pigmentosa, solitary mastocytoma, diffuse cutaneous mastocytosis and telangectasia macularis eruptive perstans. Systemic mastocytosis can be with or without cutaneous lesions. Juvenile xanthogranuloma is the most common non-Langerhans cell type of histiocytosis. Usually it is a self-limited disease. Xanthomas are group of infiltrates of foamy macrophages. They are often associated with hyperlipidemias although others may be normolipemic. Langerhans cell histiocytosis is a histioctytic disorder characterized by proliferation and accumulation of Langerhans cells into a variety of organs. Merkel cell carcinoma is a rare malignant primary cutaneous neoplasm with epithelial and neuroendocrine differentiation. The cell of origin remains unresolved.
Eyelid Merkel cell carcinoma in a patient treated with golimumab
Published in Orbit, 2018
H Hanafi, R.M Verdijk, D Paridaens
Purpose: To describe a clinical case of biopsy-proven Merkel cell carcinoma of the eyelid following golimumab therapy for rheumatoid arthritis (RA). Methods: Interventional case report. Results: A 73-year-old woman with a history of chronic RA presented with a right upper eyelid mass. She had been treated with golimumab (tumor necrosis factor (TNF) inhibitors) injection therapy for the past 6 months. A biopsy showed findings suggestive of a Merkel cell carcinoma of the eyelid. Conclusions: Merkel cell carcinoma may be associated with anti-TNF treatment and should be included in the differential diagnosis of an eyelid tumor in patients treated with TNF inhibitors.
A case series of Merkel cell carcinoma of the eyelid: a rare entity often misdiagnosed
Published in Orbit, 2019
Adriana Iuliano, Fausto Tranfa, Lidia Clemente, Federica Fossataro, Diego Strianese
Merkel cell carcinoma (MCC) is one of the rarest eyelid tumors, with high mortality rate due to lymphatic and metastatic spread. We hereby report six cases of patients with histological diagnosis of MCC referred to our Orbit Unit between 2012 and 2018, focusing on diagnosis, treatment, and subsequent follow up. All patients underwent surgical excision and systemic work-up. Both MCC TNM and eyelid MCC TNM were used to stage lesions. MCC of the eyelid is usually misdiagnosed as benign or other malignant lesions. A prompt examination and a wide local excision are mandatory. A close follow-up of these patients is advised due to high recurrence rate and lymphatic spread.
Immune evasion mechanisms and immune checkpoint inhibition in advanced merkel cell carcinoma
Published in OncoImmunology, 2017
Dirk Schadendorf, Paul Nghiem, Shailender Bhatia, Axel Hauschild, Philippe Saiag, Lisa Mahnke, Subramanian Hariharan, Howard L. Kaufman
Merkel cell carcinoma (MCC) is a rare skin cancer caused by Merkel cell polyomavirus (MCPyV) infection and/or ultraviolet radiation–induced somatic mutations. The presence of tumor-infiltrating lymphocytes is evidence that an active immune response to MCPyV and tumor-associated neoantigens occurs in some patients. However, inhibitory immune molecules, including programmed death-1 (PD-1) and programmed death-ligand 1 (PD-L1), within the MCC tumor microenvironment aid in tumor evasion of T-cell–mediated clearance. Unlike chemotherapy, treatment with anti–PD-L1 (avelumab) or anti–PD-1 (pembrolizumab) antibodies leads to durable responses in MCC, in both virus-positive and virus-negative tumors. As many tumors are established through the evasion of infiltrating immune-cell clearance, the lessons learned in MCC may be broadly relevant to many cancers.