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PubMed2006

Merkel cell carcinoma: a report of 34 cases and literature review.

BACKGROUND: Merkel cell carcinoma (MCC) is a rare and aggressive skin cancer, with unclear histogenesis. To date there is no consensus on the optimal treatment of this neoplasm, with controversy surrounding the use of radiotherapy and chemotherapy. There are also limited data on biological behaviour and prognosis, with reported survival ranging from 31% at three years to 74% at five years. METHOD: The medical records of 34 patients with a diagnosis of primary MCC, treated at two NHS trusts in Birmingham and Coventry, were reviewed. An extensive review of the English literature was also performed. RESULTS: MCC occurred predominantly in Caucasians (97%) with a mean age of 75 years. Identified risk factors were a previous history of SCC (37%), BCC (18%) and AK (20%). Ten percent of patients showed evidence of immunocompromise. Most tumours were located on the extremity, where they reached a mean size of 2.1cm. Fifty percent had regional metastasis during the course of their disease. A sub group analysis of the excision margins showed that a 2-cm excision margin, extending to the deep fascia, resulted in a 50% incomplete excision rate and a 33% local recurrence rate. In contrast a 3-cm margin including deep fascia resulted in no incomplete excisions and a 10.5% local recurrence rate Prognosis was poor with a 40% 3-year survival. Combining the data from two trusts has produced a relatively large series and highlighted differences in patient characteristics and management between the units. We advocate a 3-cm excision margin, including fascia wherever possible, combined with post-operative radiotherapy to offer the best chance of local control. Survival is fairly dismal and in keeping with the aggressive nature of this tumour. The respective roles of radiotherapy and chemotherapy remain controversial.

Aged↗
PubMed1985

Neuroendocrine (Merkel cell) carcinoma of the vulva: a case report and review of the literature.

The clinical and pathologic features of a vulvar neuroendocrine (Merkel cell) neoplasm are presented. Cytologic studies of material obtained from needle aspiration suggested that the tumor was a small cell neoplasm possibly of neuroendocrine derivation. The light-microscopic findings of sheets of small, uniform cells were consistent with a diagnosis of neuroendocrine tumor. The electron-microscopic characteristics, including the presence of neurosecretory granules, confirmed the diagnosis of a neuroendocrine (Merkel cell) carcinoma. Regional lymph node metastases were present at the time of initial surgery, and both local and distant metastases developed 8 months later. A comprehensive pretreatment metastatic evaluation is recommended. The role of chemotherapy for primary therapy is considered.

Aged↗
PubMed1997

Immunohistochemical characterization of HSP, alpha-MSH, Merkel cells and neuronal markers in acute UV dermatitis and acute contact dermatitis in vivo.

OBJECTIVE: To study the immunoneurocrine network in inflammatory dermatoses, we investigated histochemically acute UV and acute contact dermatitis. METHODS: Antibodies were applied to frozen and paraffin specimens of human skin after irradiation (n = 10), to positive patch tests (n = 10) and controls (n = 10) against: HSP 70, 72, 27, neuronal polypeptides (alpha-MSH, NSE, bombesin, PGP 9.5, NGF, NGF-R) and intermediate filaments (peripherin, NF 200, CK 19, 20). RESULTS: HSPs and alpha-MSH were upregulated in UV dermatitis in the epidermis compared to contact dermatitis and normal skin. Sunburn cells did not express HSPs or alpha-MSH in UV dermatitis. Neuronal markers and HSP 27 labeled more nerve fibers in UV than in contact dermatitis, except the increased staining for NGF, NGF-R and alpha-MSH in nerve fibers in contact dermatitis. In UV dermatitis, 50% of Merkel cells were suprabasal, but in contact dermatitis, basal, rounded and reduced in number. CONCLUSIONS: Merkel cells, HSPs and markers of neuroinflammation are of different importance in UV and contact dermatitis in vivo.

Apoptosis↗
PubMed1985

Secondary neuroendocrine carcinomas of the skin. An immunohistochemical comparison with primary neuroendocrine carcinoma of the skin ("Merkel cell" carcinoma).

Since the initial clinical presentation of visceral neuroendocrine carcinoma is occasionally a cutaneous metastasis, diagnostic confusion with primary neuroendocrine carcinoma of the skin (Merkel cell carcinoma) may ensue. In this study, seven cases of secondary cutaneous neuroendocrine carcinoma were immunohistochemically compared with twenty-one Merkel cell carcinomas for ten antigenic moieties that have been associated with endocrine tumors. Six of seven secondary tumors stained for bombesin, leucine enkephalin, methionine enkephalin, or beta-endorphin, none of which was detected in the primary cutaneous neuroendocrine carcinomas. These data suggest that immunohistochemical study may be useful in separating primary from secondary neuroendocrine tumors of the skin and may assist in directing clinical attention to the most probable site of visceral neoplasia.

Adult↗
PubMed1990

Electron microscopic immunogold cytochemistry reveals chromogranin A confined to secretory granules of porcine Merkel cells.

By ultrastructural immunohistochemistry using the immunogold technique, immunoreactive (ir) Chromogranin A (CGA) was found to be confined to the secretory vesicles of porcine Merkel cells. CGA was present predominantly in the periphery of the electron-dense core and on the clear halo. These findings indicate that CGA is a regular constituent of Merkel cell secretory granules but probably not exclusively responsible for their electron opacity.

Animals↗
PubMed2004

All delays before radiotherapy risk progression of Merkel cell carcinoma.

Prolonged waiting times for radiotherapy have resulted in many centres assigning priorities to various patient or diagnostic groups. A high risk of progression on a waiting list is one factor that would reasonably influence the priority. The present descriptive study of 27 patients with Merkel cell carcinoma (MCC) found that a median wait of 24 days for radiotherapy is associated with a high risk of progression. Eleven (41%) of 27 patients developed progressive disease, including five (45%) of 11 patients waiting for adjuvant radiotherapy. Patients treated adjuvantly also had longer waiting times prior to their initial radiotherapy consultation (median 41 days), which may have contributed to the rate of progression. Merkel cell carcinoma is an aggressive but curable malignancy and appropriate management should include efforts to minimize all potential delays prior to the commencement of radiotherapy.

Carcinoma, Merkel Cell↗
PubMed1985

[Merkel cell carcinoma of the skin. Anatomoclinical, ultrastructural and immunohistochemical study of 14 cases].

The clinical and pathological features of 14 cases of Merkel cell carcinoma are reported. They commonly arise in the skin of elderly patients, particularly on the face and pelvis. They have a loco-regional aggressivity (nodal metastases in 4 cases) but some patients die with disseminated metastases (2 cases). These tumors are composed of round cells with scanty cytoplasm, arranged in solid or trabecular sheets. Mitotic figures are usually numerous. The ultrastructural study reveal secretory granules and paranuclear collection of intermediate filaments. Immunohistochemical phenotype is highly characteristic: cytoplasmic diffuse positivity with an anti-neuron-specific enolase polyclonal antibody; polar and/or diffuse positivity with anti-cytokeratin, anti-epithelial membrane antigen and anti-S100 protein monoclonal antibodies; polar positivity with an anti-neurofilament monoclonal antibody. The negativity with an anti-common leucocyte antigen monoclonal antibody is helpful to differentiate Merkel cell carcinoma from cutaneous malignant lymphoma.

Adult↗
PubMed1990

[A case of Merkel cell carcinoma of the eyelid].

An 84-year-old man with Merkel cell carcinoma in the right upper-eyelid is reported. The patient presented with a rapidly growing, reddish-purple, solid tumor with a relatively well-defined margin in the skin of the lid. Increased neuron specific enolase content in the blood returned to normal several months after resection of the tumor and 70 Gy postoperative cobalt radiation. Histopathologic examination of the resected specimen revealed that the tumor was limited by intact epidermis and occupied by moderate-sized, round malignant cells with marked mitoses and scant cytoplasm. The neoplastic cells were positively stained by labeled antibodies for neuron specific enolase, keratin and epithelial membrane antigen. Electron microscopic examination showed abundant perinuclear microfilaments and dense core granules.

Aged↗
PubMed1987

Merkel cell tumor coexpressing cytokeratin and neurofilament proteins.

Whorled filaments 10 nm in width were identified by anti-intermediate filaments antibodies in a Merkel cell tumor from a 52-year-old man. Immunohistochemical tests revealed that the tumor was stained with anti-keratin antibody and antibodies against the 68-kd and 200-kd subunits of neurofilament proteins but not antibody against the 150-kd subunit. This is the first reported case of Merkel cell tumor expressing a 200-kd subunit of neurofilament proteins.

Humans↗
PubMed1992

Trabecular (Merkel cell) carcinoma of the skin. A case report.

A case of trabecular (Merkel cell) carcinoma of the skin is reported. The lesion appeared on the back, recurred locally twice and metastasized to the intra-abdominal lymph nodes 7 years later. Its unusual primary site, as well as the development of prostatic adenocarcinoma are the main characteristics of the case presented.

Adenocarcinoma↗
PubMed2000

Recurrent Merkel cell carcinoma of the upper extremity.

We report a case of recurrent Merkel cell carcinoma (MCC) of the upper extremity, treated aggressively with wide local excision, regional lymphadenectomy, and immediate reconstruction. Five years after surgery, there is no clinical or diagnostic evidence of locoregional recurrence or distant disease. The patient's upper extremity and hand remain fully functional, without evidence of median or ulnar nerve dysfunction. No donor site morbidity has been noted.

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PubMed2003

Merkel cell carcinoma: a report of gastrointestinal metastasis and review of the literature.

Merkel cell carcinoma (MCC) is an uncommon, highly aggressive cutaneous neoplasm of neuroendocrine differentiation with a poor prognosis. MCC most often presents as a painless, firm, raised lesion in sun-exposed sites of the head and neck region of the elderly. We report a case of a metastatic MCC to the stomach presenting as upper gastrointestinal bleeding. To our knowledge, this is the second reported case of MCC presenting as upper gastrointestinal bleeding and the first case confirmed by the newer immunohistochemical techniques. The literature is reviewed.

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PubMed1994

[Merkel cell carcinoma of the skin].

This study reports five cases of Merkel-cell carcinoma of the skin. Then the authors review the present state of the art from the data already available in the literature concerning this malignant primary skin tumor. A part from local excision, no standard procedures are described. The literature provides a lot of discrepancies concerning the additional treatments such as lymph mode excision, radio and chemotherapy. The prognosis of this tumor remains poor because of a high incidence of local recurrence, a frequent spread to regional lymph modes and the development metastases.

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PubMed2004

[Merkel cell carcinoma of penis].

We describe the second case in literature of Merkel cell carcinoma of penis, a rare, very aggressive neuroendocrine tumor. Treatment is debatable in view of the fact that this kind of tumor has unpredictable biological behaviour, early regional lymph node involvement, early distant metastases and a high recurrence rate. Considering these facts, we used pre-operative lymphoscintigraphy, intra-operative lymph node mapping and sentinel node biopsy before performing a bilateral inguinal lymphadenectomy. All lymph nodes removed from each inguinal region were cancer-free. Although the patient had received a cycle of adjuvant chemotherapy he developed inguinal recurrence and iliac metastasis.

Carcinoma, Merkel Cell↗
PubMed1995

[Cervicofacial involvement of primary cutaneous neuroendocrine carcinomas or Merkel cell tumors: therapeutic considerations].

Seven cases of primary skin neuroendocrine carcinoma or Merkel cell tumours with cervico-facial localization are reported. The poor prognosis of these tumours is essentially due to the potential for local recurrence and the frequency of locoregional and visceral metastasis. Surgical treatment is required but rarely sufficient to control the disease. Complementary radiotherapy, when performed early, can reduce the rate of locoregional recurrence. Lymph node resection is important to determine prognosis but has not been proven to improve outcome. In addition, parotid metastasis appears to result from blood stream dissemination and has a very poor prognosis. Exclusive radiotherapy may be discussed in such cases.

Adult↗
PubMed1997

[Merkel cell carcinoma: follow-up of 10 patients. Current diagnosis and therapy].

Merkel cell carcinoma (MCC) is a rare neoplasm of the skin predominantly found on the head and extremities. Clinically MCC presents as a rapidly growing red or violaceous, dome-shaped, solitary tumor. The clinical and histological diagnosis of MCC remains difficult. Distinction from poorly differentiated small cell primary tumors or metastasis requires immunohistochemical analysis and-if available-electron-microscopic studies. We report on the follow-up of 10 patients with MCC treated in the past 6 years at our department. In nine patients the tumors were completely removable; in one patient with a large primary tumor of the upper lip no histologically proven complete excision could be performed. After a median follow-up of 42 months, local recurrence or lymph node involvement was observed in three patients. Two patients died following disseminated metastases, one elderly patient due to cardiac insufficiency. Our observations demonstrate that MCC is a potentially aggressive cutaneous tumor. Adequate primary surgical and adjuvant therapy as well as careful follow-up are mandatory.

Aged↗