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Query: UMLS:C0027627 (metastases)
 103,950 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Molecular characterization of neuroendocrine (Merkel cell) carcinoma of the skin. Review of the literature and report of three cases. Although neuroendocrine carcinoma of the skin (NECS) is comparatively a rare clinical-histological entity, numerous morphological and ultrastructural studies have been carried out since the tumor was identificated by Toker (1972). Recently immunocytochemistry has allowed a better molecular characterization (immunophenotype) of this tumor and a more exact diagnosis. The main problem for the pathologist is the differential diagnosis between NECS and skin neoplasms--both primitive and metastatic--which require a more aggressive treatment. Often the classical morphological criteria do not distinguish NECS from non-Hodgkin's lymphoma, amelanotic melanomas, cutaneous metastases of lung small cell carcinoma or of neuroblastoma. The co-expression of cytokeratins and neurofilaments constantly found in NECS, is surely the best differential criterion from non-neuroendocrine carcinomas. Furthermore, the typical paranuclear location of both the intermediate filaments in NECS is a distinctive peculiarity as opposed to lung microcytoma, where cytokeratins and neurofilaments, when present, show widespread perinuclear positivity. Chromogranin A is found only in a small percentage of tumor cells, whilst synthesis of calcitonin, somatostatin, gastrin, ACTH, is very rare. Finally, the lack of common leukocyte antigen (CLA), S-100 protein and vimentin in NECS rules out the diagnoses of lymphoma, melanoma and sarcoma respectively.
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PMID:[Molecular characterization of cutaneous neuroendocrine (Merkel cell) carcinoma. Review of the literature and presentation of a caseload]. 209 Oct 10

Between 1966 and 1987, 54 patients with non-disseminated Merkel cell carcinoma (MCC) were treated with curative intent at the University of Texas M. D. Anderson Cancer Center. The primary tumor site was in the head and neck in 38 patients. The majority of the patients (57%) were referred with locoregionally recurrent disease. For the whole group, survival was 30% after 5 years. Patients who presented with nodal involvement had a median survival of 13 months compared with 40 months for node-negative patients (p less than .04). Only 4/37 patients treated initially by surgery alone were locoregionally controlled, with a median time to recurrence of 4.9 months. Salvage with radiation therapy was attempted in 18 patients (after additional surgery in 14), but was successful in only four. The predominant failure pattern in this subgroup was distant metastases, occurring as a component of initial recurrence in 12/18 patients. Prior to 1982, the philosophy of initial therapy was to give postoperative irradiation only to patients with large primaries or nodal involvement. Subsequently, postoperative radiotherapy has been recommended routinely, and all five patients treated with this approach remain disease-free. In total, 31 patients (including 10 patients with gross disease) were irradiated at M. D. Anderson; only one developed an in-field locoregional recurrence as an initial site of failure. However, three marginal recurrences occurred. The median dose to the primary tumor, first echelon nodes, and supraclavicular nodes was 60, 51, and 50 Gy, respectively. Our current recommendation for initial treatment is excision of the primary tumor followed by irradiation with generous fields to include the primary tumor site and draining regional lymphatics to doses of 46-50 Gy in 2 Gy fractions. For gross unresected disease, 56-60 Gy is recommended. The role of adjuvant systemic therapy remains to be defined.
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PMID:The essential role of radiation therapy in securing locoregional control of Merkel cell carcinoma. 221 Dec 7

Merkel cells are clear oval cells in the epidermis and outer root sheaths of hair follicles, which are probably of epithelial origin, share ultrastructural features with neuroendocrine cells, and are found in association with touch receptors. In the eyelid, they occur singly in the epidermis and external root sheaths of hairs and eyelashes, and in specialized touch spots alternating with eyelashes. Their typical electron microscopical and antigenic features include dense-core granules, intranuclear rodlets, spinous processes, and a positive reaction for specific cytokeratins, epithelial membrane antigen, neuron-specific enolase, chromogranin and synaptophysin. Merkel cell carcinoma probably develops from precursor cells which give rise to keratinocytes and Merkel cells, and nearly one out of ten Merkel cell carcinomas occur in the eyelid and periocular region. They tend to be bulging lesions near the lid margin of elderly patients, reddish in color, and erythematous with telangiectatic vessels. The diagnosis is based on the frequent presence of neurofilaments and paranuclear aggregates of intermediate filaments in addition to features typical of normal Merkel cells. The tumor often mimics lymphoma or undifferentiated carcinoma and frequently invades lymphatic vessels. One third of Merkel cell carcinomas recur, almost two thirds give rise to regional node metastases, and up to one half metastasize widely and result in death. Initial treatment should be prompt and aggressive, with wide resection and routine postoperative irradiation. Although metastatic lesions often respond to radiation therapy and cytostatic drugs, these treatments are mainly of palliative value.
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PMID:The Merkel cell and associated neoplasms in the eyelids and periocular region. 227 47

A rare case of intestinal metastasis of a neuroendocrine carcinoma of the skin (Merkel Cell Tumor) is reported. The primary tumor was excised from the left arm two years earlier and followed an aggressive course with lymph-nodes, tonsillar and intestinal spread. Histologically, the intestinal lesion was similar to the primary tumor with small, undifferentiated cells. Undifferentiated small cell carcinoma and lymphomas of the gastrointestinal tract are to be considered in the differential diagnosis. Merkel Cells Tumor usually affects head and neck (44%) and extremities (48%), and is a highly malignant neoplasia, with early recurrence and distant metastases. Wide surgical excision of the primary lesion is the treatment of choice, while controversial is the role of prophylactic regional lymphadenectomy. Adjuvant radio- and chemo-therapy is frequently associated.
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PMID:[A rare case of Merkel's tumor with intestinal metastases]. 229 8

Merkel cell tumor is an unusual, aggressive malignancy of skin that has been considered to be derived from cutaneous Merkel cells. We are reporting a case of Merkel cell tumor overlying the left scapula with metastases to the thoracic spine and pleura. The tumor was found incidentally in a 23-year-old pregnant black woman. The tumor recurred locally 5 months after initial wide excision. Subsequently, a second wide excision of the recurrent tumor with ipsilateral axillary dissection was performed. The course of the disease was complicated by local recurrence and formation of distant metastases to pleura and spine. At the end-stage of the disease, the patient was found to have a cardiac murmur, and echocardiography revealed a mass in the anterior wall of the right ventricle that was suspicious for a metastatic lesion. The patient expired from extensive distant metastases 23 months after diagnosis.
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PMID:Merkel cell tumor of the back detected during pregnancy. 236 85

Thirteen cases of primary endocrine carcinoma of the skin (Merkel cell carcinoma) were reviewed with the aim of defining the morphological, immunohistochemical and ultrastructural criteria for diagnosis. The tumour cells were characterized by their scanty cytoplasm, generally small uniform nuclei with finely dispersed chromatin and multiple small nucleoli. Nuclear shapes varied from round to spindle, with larger and pleomorphic forms predominating in 2 tumours. A striking feature seen in 12 tumours was the occurrence of a "ball-in-mitt" pattern represented by 1 or 2 crescentic tumour cells closely wrapped around an oval cell. Staining for neuron-specific enolase was the most consistent marker of the tumour and the characteristic juxtanuclear globular staining for keratin and cytokeratin and the occasional coexpression of neurofilament set this tumour apart from other cutaneous neoplasms, in particular, metastatic carcinoid tumours and oat cell carcinoma from the lung. The fine structural features of note were striking paranuclear or juxtanuclear whorls of intermediate filaments, seen in 7 cases, the presence of variable numbers of membrane-bound dense core granules of 80-150 nm diameter in all cases and cytoplasmic spinous or microvillous projections containing microfilaments in 4 cases. Less consistent characteristics of primary endocrine carcinomas of the skin included cell moulding, argyrophilia and immunohistochemical staining for ACTH, VIP and calcitonin. The high frequency of vessel invasion in this series is in keeping with the high rate of local recurrence, lymph node metastases and visceral dissemination reported. The distinction from other similar appearing tumours in the skin is discussed.
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PMID:Criteria for the diagnosis of primary endocrine carcinoma of the skin (Merkel cell carcinoma). A histological, immunohistochemical and ultrastructural study of 13 cases. 243 4

Case report of a rare eyelid tumor in an 83-year-old woman. The excised lesion was classified as a neuroendocrine Merkel cell carcinoma on the basis of histologic, ultrastructural, and immunohistochemical examination. Detection of neurosecretory granules by electron microscopy and the characteristic cytokeratin and neurofilament pattern supported the diagnosis. The patient developed a local recurrence, which was successfully removed. There is no evidence of regional or distant metastases.
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PMID:[Merkel cell carcinoma of the upper eyelid]. 244 47

The neuroendocrine carcinoma of the skin has its histogenetic origin in Merkel cells and a preference in head and neck area in the seventh decade of life. The definitive diagnosis can be made with a combination of electron microscopy and immunohistochemistry. Merkel cell carcinoma is a primary cutaneous neoplasma and is rarely found on the lips or gingiva. Operation and radiation are the therapy of choice. The value of an additional antineoplastic chemotherapy in the treatment of Merkel cell carcinoma is still controversial. Although long survival times had been described in literature the occurrence of local relapses and metastases demands for frequent controls.
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PMID:[Neuroendocrine carcinoma (Merkel cell tumor) in the head and neck area]. 244 25

Neuroendocrine (Merkel cell) carcinoma of the skin is a rare entity. Often locally aggressive, this lesion may also metastasize to organ systems, including bone, liver, and brain. The authors report a case of a 64-year-old male who presented with hoarseness and dysphagia 17 months after resection of a primary Merkel cell carcinoma of the nose. Additional studies revealed bilateral vocal cord paralysis secondary to central nervous system dysfunction. Cytologic evaluation of the cerebrospinal fluid revealed malignant tumor cells consistent with metastatic Merkel cell carcinoma. Presented are the cytologic and immunohistochemical findings in a case of metastatic Merkel cell carcinoma involving the central nervous system.
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PMID:Cytologic and immunohistochemical diagnosis of neuroendocrine (Merkel cell) carcinoma in cerebrospinal fluid. 247 4

The clinico-morphological features in 13 patients (nine female) with neuroendocrine carcinoma of the skin are presented. The mean age was 64.9 years. The limbs were the most common site of primary tumour, followed by the face. The clinical course was characterized by a high incidence of regional lymph node metastases (69%) and recurrences (46%). Seven of the patients died of tumour, with a mean survival time of 13 months. Histologically, a solid pattern of tumour growth was most common. The cells were usually small and uniform. Squamous cell differentiation was found in one tumour. The cell of all tumours reacted positively for cytokeratins and neuron-specific enolase. The positive reaction frequently had a ball-like globular pattern, corresponding to inclusion-like bodies seen on light microscopy and to paranuclear whorls of intermediate filaments observed on electron microscopy. Neurosecretory granules were seen on electron microscopy in the 11 cases examined and in one case a 'Luse body' was found in the intercellular space.
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PMID:Neuroendocrine (Merkel cell) carcinoma of the skin: a clinico-morphological study of 13 cases. 248 Sep 35


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