1/9. Complete spontaneous regression of Merkel cell carcinoma: a review of the 10 reported cases.BACKGROUND: Merkel cell (neuroendocrine) carcinoma (MCC) is a very aggressive primary cutaneous neoplasm occurring most often on the head and neck of the elderly. Complete spontaneous regression (CSR) of MCC was first described in 1986. Since then other cases have been reported bringing the total to 10. OBJECTIVE: To review these 10 cases and obtain long-term follow-up data, to compare them for similarities and differences. METHOD: Each original case report was extensively reviewed and authors contacted in most cases for confirmation and updated information. RESULTS: In no case did MCC recur after CSR was noted, although follow-up information in some cases was short. When CSR occurred, it was swift and dramatic with complete regression of skin and lymph node metastasis in 1-3 months. CONCLUSION: While only 10 cases of CSR is a small number, MCC is itself a rare malignancy with just over 600 reported cases. Today most cases of MCC receive aggressive combined therapy effectively precluding diagnosis of CSR. The nature of regression in these 10 cases may point toward future immunologic therapy just as similar cases of CRS in patients with melanoma have led to advances in the immunologic treatment for that malignancy.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
2/9. Clinicopathologic and electron microscopic study of cutaneous neuroendocrine (Merkel cell) carcinoma in a cat with comparisons to human and canine tumors.Malignant neuroendocrine carcinoma of the skin (Merkel cell tumor) was diagnosed in an 18-year-old spayed female maine Coon Cat. The diagnosis was made on the basis of morphologic and electron microscopic findings. The cat was euthanatized 321 days after surgical excision of the tumor. The tumor's malignancy contrasted with the benign nature of Merkel cell tumors reported in dogs and was consistent with the malignancy of Merkel cell tumors reported in humans.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
3/9. Merkel cell carcinoma of the eyelid: a report of two new cases and a review of the literature.Merkel cell carcinoma is a cutaneous neoplasm that rarely occurs in the eyelid. The tumor has an aggressive nature with high local recurrence and metastases rates. early diagnosis and prompt complete excision with frozen section monitoring of margins are recommended.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
4/9. Merkel cell carcinoma: a case report with treatment summary and updates.Merkel cell carcinoma (MCC) is a rare primary cutaneous neoplasm known for its propensity to develop early regional and distant metastasis. Fewer than 400 cases occur annually in the united states. MCC ranks as the most deadly of cutaneous malignancies, with a fatality rate of approximately 25%. Because of its aggressive nature, MCC is often resistant to surgery, radiation, and chemotherapy regimens. Standardized treatment patterns have not been established, and difficulty arises finding appropriate treatment for the elderly, who comprise the majority of patients with MCC.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
5/9. Neuroendocrine carcinoma of the skin (Merkel cell carcinoma) in a black.Neuroendocrine carcinoma of the skin is an uncommon, small-cell neoplasm most commonly found on white, sun-exposed skin. Diagnosis by clinical and histologic means may be difficult. Immunohistochemical and ultrastructural analysis are often required. Because of the aggressive nature of neuroendocrine carcinoma of the skin, prompt diagnosis and treatment are essential. We present the rare occurrence of a neuroendocrine carcinoma of the skin on sun protected skin in a black. Clinical, histologic, immunohistochemical, and ultrastructural features are reviewed, and therapeutic options are discussed.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
6/9. Concurrent spindle cell peripheral pulmonary carcinoid tumor and Merkel cell tumor of the skin.To our knowledge this is the first reported case of concurrent Merkel cell (trabecular carcinoma) tumor and peripheral pulmonary carcinoid tumor. Both tumors are considered to neuroendocrine in nature. The significance of concurrent neuroendocrine tumors is described with respect to multiple endocrine neoplasia syndrome variants and possible pathophysiology.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
7/9. Merkel cell carcinoma.Merkel cell carcinoma is an unusual primary cutaneous tumor with an aggressive biologic nature. Following surgical treatment, 40% of patients have local recurrences develop, 55% have regional lymph node metastases develop, and 49% have distant metastases develop. We have treated four patients with Merkel cell carcinoma; only one of the four patients was alive and well after 2 years. Two patients died of metastatic disease, one at 11 months following initial treatment and one at 39 months. The fourth patient had a rapid recurrence following initial treatment and is currently in remission following chemotherapy for regional metastases. Recent reports indicate that chemotherapy may be helpful in treating patients with recurrent or metastatic Merkel cell carcinoma.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
8/9. Cutaneous lymphoma-simulating Merkel cell carcinoma-molecular genetic demonstration of a clonal disease with divergent immunophenotypes.Merkel cell carcinoma and malignant lymphoma are important differential diagnoses for undifferentiated cutaneous round cell tumors and immunohistochemistry is instrumental in their evaluation. We describe a case of a 73-year-old man who had cutaneous large cell lymphoma in the right leg (immunophenotype CD45 , CD19 , CD20 CD22 , lambda clonal, cytokeratin-, NSE-) and lymphoma in left leg simulating Merkel cell carcinoma showing absence of leukocyte antigens (CD45-, CD20-, no light chains) and focal expression of keratin and NSE. However, analysis of polymerase chain reaction amplification products of dna extracted from both lesions showed two amplifiable sharp bands indicating clonal rearrangements of both alleles of the immunoglobulin heavy chain. Cloning and sequencing of the products from left and right leg lesions showed either 100% homology (one band), or close similarity (the other band), indicating that both tumors were derived from the same B-cell lymphoma clone. This case shows the value of polymerase chain reaction and sequencing in analyzing the ultimate nature of lymphoproliferations and illustrates the potential limitations of immunophenotyping.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |
9/9. Aggressive skin cancers in a cardiac transplant recipient.skin cancers following cardiac transplantation are a serious problem that may lead to significant morbidity and mortality. While the majority of skin cancers represent minimally invasive lesions that are treated adequately by local means, a small subset exhibits a potentially life-threatening natural history. The aggressiveness of these skin cancers, despite standard treatment, is indicative of the aggressive nature displayed by a subset of secondary malignancies following cardiac transplantation. The need for lifelong maintenance immunosuppression after transplantation is a major factor in the development of these secondary malignancies. Presented here is the case study of a cardiac transplant recipient who developed multiple aggressive squamous and non-squamous cell scalp skin cancers.- - - - - - - - - - ranking = 1keywords = nature (Clic here for more details about this article) |