China
Africa
Explore chapters and articles related to this topic
Viral neuro-oncogenesis: Polyomaviruses and brain tumors
Published in Avindra Nath, Joseph R. Berger, Clinical Neurovirology, 2020
Martyn K. White, Sidney E. Croul, Kamel Khalili
Perhaps the most exciting recent development in polyomavirus tumorigenesis is the discovery of Merkel cell carcinoma virus (MCV). MCV is the most recent human oncogenic virus to be discovered [38] and is the only proven oncogenic human polyomavirus [39]. Merkel cell carcinoma is a rare but highly aggressive neuroectodermal tumor that may arise from mechanoreceptor Merkel cells of the skin [40]. Since immunosuppression is a predisposing factor, it was surmised that it may have an infectious etiology. Feng et al. [38] searched for viral sequences in Merkel cell carcinoma using digital transcriptome subtraction, which led to the discovery of a novel transcript with a sequence homologous to the T-antigen of polyomaviruses. The virus was designated MCV, a novel circular polyomavirus, which was clonally integrated into the cell genome in ~80% of cases of Merkel cell carcinoma MCC [38]. This integration event occurs at a single site in the cell genome indicating that integration preceded the expansion of the tumor, which is important evidence for the role of MCV in tumorigenesis. Subsequent studies confirmed that integration of MCV occurs in many cases of Merkel cell carcinoma and provided molecular evidence for a causative role of this virus in tumorigenesis [39].
Benign Lymph Node Lesions
Published in Harold R. Schumacher, William A. Rock, Sanford A. Stass, Handbook of Hematologic Pathology, 2019
Once the diagnosis of Merkel cell carcinoma was established, it was recommended to thoroughly evaluate the patient for evidence of a primary lesion in the skin. In this case, no lesion was identified. The diagnosis of metastatic Merkel cell carcinoma in a lymph node in the absence of an identifiable primary lesion in the skin is extremely rare and always difficult to explain, but there have been sporadic reports and case presentations of such occurrences. One report included eight patients with Merkel cell carcinoma with involvement of the inguinal lymph nodes (five cases), axillary lymph nodes (two cases), and submandibular lymph nodes (one case) in which no primary skin lesion was found. In all these cases, the patients underwent extensive evaluation, and rigid criteria were followed in making the diagnosis of Merkel cell carcinoma (2).
Neurogenic tumors
Published in Eckart Haneke, Histopathology of the NailOnychopathology, 2017
Merkel cell carcinoma is a rare cutaneous malignant neoplasm first described as trabecular carcinoma.60 Other synonyms are cutaneous neuroendocrine carcinoma, cutaneous APUDoma, and primary small cell carcinoma of the skin. Most patients are Caucasians;61 it is exceptional in black individuals. It is about double as frequent in men as in women. Sun-exposed skin is the main location. Etiologically, chronic sun damage and immunosuppression were thought to be responsible, but recently a specific virus, the Merkel cell polyomavirus (MCPyV), was identified in about 80% of the cases.62–65 Head and neck as well as extremities are mainly involved whereas digital localization is very rare. The tumors are solitary, dome-shaped, painless, red to violaceous, and have a fast growth rate. Most nodules are around 2 cm in diameter, but larger tumors may occur.66 Merkel cell carcinomas have a high local recurrence rate and tend to metastasize to the regional lymph nodes until they finally spread hematogenously and/or via the lymphatics.67 Early and radical surgery is indicated, and many authors recommend postoperative radiotherapy.
Avelumab: a new standard for treating metastatic Merkel cell carcinoma
Published in Expert Review of Anticancer Therapy, 2018
Mairead Baker, Lisa Cordes, Isaac Brownell
Merkel cell carcinoma is a rare and aggressive neuroendocrine skin cancer that more commonly affects sun-exposed fair skin, immunocompromised patients, and the elderly. The mean age at diagnosis is 75 and approximately 37% of patients have nodal disease at presentation whereas 5–12% present with metastatic disease [1–4]. In patients with metastatic disease, the 5-year survival rate is estimated to be 0–18% [3,5]. MCC is the second leading cause of skin cancer deaths and, per case, is twice as lethal as melanoma, with a relative mortality between 33% and 46% [4,6,7]. First described in 1972, worldwide incidence and mortality from MCC has risen dramatically over the past few decades, and MCC annual incidence is now estimated to be 0.2, 0.7, and 1.6 cases per 100,000 people in Europe, the USA, and Australia, respectively [4,8–10].
Eyelid Merkel cell carcinoma in a patient treated with golimumab
Published in Orbit, 2018
H Hanafi, R.M Verdijk, D Paridaens
Merkel cell carcinoma is a very rare type of skin malignancy. It tends to grow quickly and to metastasize (through a lymphatic route) at an early stage. A study by Herbet et al. concluded that the mainstay of treatment for Merkel cell carcinoma of the eyelid is wide local excision with margin control, whereas the use of radiotherapy is institution specific.7 Merkel cell carcinoma is associated with regional nodal and distant metastatic disease. Based on their study, they suggested for a sentinel lymph node biopsy or strict regional lymph node surveillance for all Merkel cell carcinoma of the eyelid, regardless of the category or size.7 A pathologic nodal evaluation has been shown to improve prognostic accuracy, and a study suggested that sentinel lymph nodes mapping and excision may be a useful adjunct in the treatment of Merkel cell carcinoma.8
PD-L1 inhibitors in the pipeline: Promise and progress
Published in OncoImmunology, 2018
Vito Vanella, Lucia Festino, Martina Strudel, Ester Simeone, Antonio M. Grimaldi, Paolo A. Ascierto
Merkel cell carcinoma is an aggressive cutaneous malignancy associated with poor survival. Chemotherapy has been shown to produce responses but they are seldom durable. In a single-arm, open-label, phase II trial, 88 patients with stage IV chemotherapy-refractory, histologically confirmed Merkel cell carcinoma were treated with IV avelumab 10 mg/kg every 2 weeks.35 Overall, 28 of 88 patients (31.8%) achieved an objective response, including 8 complete responses and 20 partial responses. Responses were ongoing in 23 patients (82%) at the time of analysis. Better responses were observed in the subgroup of patients who had received fewer lines of previous therapy, probably because these patients had a more functional immune system. Avelumab was well tolerated, with 5 grade 3 treatment-related AEs. The most common AEs were fatigue, diarrhea, nausea, asthenia and infusion-related reactions. Three patients permanently discontinued treatment because of an AE. These findings indicate that checkpoint inhibitors could become the standard of care as first-line treatment of advanced Merkel cell carcinoma.