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PubMed1998

Radiolocalization of the sentinel lymph node in Merkel cell carcinoma: a clinical analysis of seven cases.

Merkel cell carcinoma (MCC) is a rare cutaneous skin lesion with a variable but often aggressive clinical course. Patient survival correlates with nodal status and the presence of distant metastases. The histologic status of the sentinel lymph node consistently correlates with the incidence of regional lymphatic metastases in other dermal malignancies. The technique of radiolocalization and surgical resection of the sentinel lymph node using an intraoperative gamma probe is used to guide clinical management in these patients. We report on seven cases of MCC managed utilizing this technique. Four patients had negative sentinel nodes and no other nodal disease at completion lymphadenectomy (n = 2) or clinical follow-up (n = 2) and currently remain disease free. Two patients had a positive sentinel node but no other positive lymph nodes at completion lymphadenectomy; one of them developed regional recurrence. One patient with a positive sentinel node and six additional positive nodes developed extensive nodal disease and systemic recurrence during radiotherapy and expired of MCC. Our results suggest that the sentinel node was identified and removed successfully using radiolocalization making this technique useful in the staging and therapy of patients with MCC.

Aged↗
PubMed2001

Merkel cell carcinoma: important aspects of diagnosis and management.

Merkel cell carcinoma (MCC) is a highly aggressive primary neuroendocrine tumor. It is suggested in the literature that postoperative radiotherapy may decrease local recurrence and improve overall survival. The purpose of this retrospective review was to determine our experience and review the literature on this aggressive malignancy. Charts of ten patients with MCC seen between 1985 and 1997 were reviewed to obtain clinicopathological data. Eight patients were male with a mean age of 72 years (range 49-90). The head and neck was the most common site, affecting 50 per cent of patients. All patients had primary excisions with documented negative margins. Pathological size ranged from 10 to 40 mm. Initial pathological diagnosis was lymphoma in three cases requiring immunohistochemistry for cytokeratin and neuron-specific enolase for definitive diagnosis. Lymphatic invasion was noted in three patients but only one of these patients had clinical lymph node involvement. The mean follow-up was 54 months (range 6-114) with an 80 per cent one-year survival and 30 per cent 2-year survival. Postoperative radiotherapy was administered to five patients. Of these three died with evidence of both local and distant recurrence. This small retrospective review highlights important points in the management of MCC including pathological diagnosis and benefits of adjuvant radiation therapy.

Aged↗
PubMed1997

Merkel cell carcinoma of palatal mucosa in a young adult: immunohistochemical and ultrastructural features.

The first case report of a merkel cell carcinoma arising from the palatal mucosa in a young adult is presented. The histopathological similarities of this tumour in skin and oral mucosa are also discussed. The patient was a 14-year-old female with a non-symptomatic painful swelling in the left molar region of the maxilla. Under the diagnosis of a malignant tumour, a partial maxillary resection was performed, but there was a recurrence, and finally the patient died of cerebral metastasis. The tumor was composed mainly of uniform small cells. Immunohistologically, a large number of the cells were reactive to neuron specific enolase (NSE) and cytokeratin CK19, and some of the cells were positive to CK8, CK13, CK20, PGP9.5 and CEA focally and slightly. Pseudo-rosette formation and squamous differentiation were frequently detected. The ultrastructure of the tumour cells showed abundant Golgi bodies associated with neurosecretory granules. We conclude that it is the first case of a Merkel cell tumour arising from palatal mucosa and invading underlying bone with reactive hyperplasia. These findings closely resemble those of the same tumour occurring in the skin

Adolescent↗
PubMed2002

Merkel cell carcinoma: five case reports using sentinel lymph node biopsy and a review of 110 new cases.

Merkel cell carcinoma is an uncommon cutaneous tumor that is considered locally aggressive and often spreads regionally through lymphatic channels. Evaluation of surgical treatment methods has been hampered by the low incidence of this tumor. Current standards of treatment include wide surgical excision and regional lymphadenectomy if clinically suspicious nodes are present. However, the development and increasing use of sentinel node imaging and biopsy have expanded the diagnostic options. This article presents information on 110 Merkel cell carcinomas treated in Connecticut between 1990 and 1997. Statistics on gender, age, disease location, treatment, and mortality are reviewed. Using the census data for Connecticut, the annual incidence for this disease was calculated to be 0.42 cases per 100,000 people. A series of five cases treated with wide excision and sentinel lymph node biopsy is also presented.

Adult↗
PubMed2002

Merkel cell carcinoma of the head and neck: a retrospective case series.

BACKGROUND: Eighty-five percent of all Merkel cell carcinomas appear on sun-exposed areas, with 50% to 55% occurring on the head and neck. METHODS: A chart review was performed on 22 patients treated for Merkel cell carcinoma of the head and neck between 1981 and 1998. RESULTS: Fifteen patients were men (68%). The average age at operation was 69.9 years (range, 24-84 years). The average duration of follow-up was 3.6 years (range, 3 days-8.6 years). Overall survival at 1, 2, and 3 years postoperatively was 78%, 68%, and 68%, respectively. The only independent predictor of survival was the type of surgical therapy. All patients who underwent wide local excision (WLE) of the primary tumor with dissection of the lymphatic drainage basin were alive at 2 years as opposed to 68% who had WLE alone and 33% who had Mohs surgery. CONCLUSIONS: WLE and dissection of the lymphatic drainage basin provided the best overall survival.

Adult↗
PubMed1993

Primary Merkel cell tumor: a clinical analysis of eight cases.

BACKGROUND: In recent years, an unusual biologic behavior of Merkel cell tumor (MCT) has been noted. In some patients, the tumor was indolent and well controlled by therapy, while in others it was lethal in a few months. Even though the majority of the reported cases are between these two biologic extremes, it seems evident that there is a high variability in the clinical course of the tumor. METHODS: A clinical analysis of eight cases of primary Merkel cell tumor was performed. All the patients presented with similar clinical features: age, tumor staging, duration of the disease, lack of complicating cutaneous or systemic diseases. On the basis of these common findings, which made this group quite homogeneous, our attempt was to identify other clinical signs that could correlate with the local recurrence and/or the onset of metastases. The outcome of our patients, in fact, was quite variable. RESULTS: The tumor size, the clinical aspect at presentation (single, multiple nodules, or plaque), the histologic pattern (all were of the trabecular type), and immunohistology did not correlate with the outcome. CONCLUSIONS: We report the rare occurrence of MCT in the perianal area, which suggests that it should be included in the differential diagnosis of perianal tumors, the very aggressive behavior of the tumor in two patients (death < 6 months from diagnosis), which confirms how the prognosis for MCT is unpredictable even if the diagnosis is established at an incipient stage and the tumor promptly removed.

Aged↗
PubMed2004

Merkel cell carcinoma and multiple basal cell carcinoma in an African albino woman with HIV infection.

A 25-year-old HIV-infected African albino woman developed an aggressive Merkel cell carcinoma on her face and at least 10 basal cell carcinomas, mainly on sun-exposed parts of her body. HIV infection, immune deficiency and sun exposure are known risk factors for the development of Merkel cell carcinoma. Chemotherapy and radiotherapy were only temporarily successful. She died shortly after surgery was performed to remove the tumour.

Adult↗
PubMed2001

Merkel cell carcinoma of the parotid gland associated with Warthin tumour: report of two cases.

AIMS: Two cases of Merkel cell carcinoma occurring simultaneously and in close association with a Warthin tumour of the parotid gland are reported. METHODS AND RESULTS: The patients were a 65-year-old man and a 70-year-old man, respectively. The Merkel cell carcinoma component was immunoreactive for chromogranin and keratin 20 and contained neuroendocrine-type granules at the ultrastructural level. CONCLUSIONS: The histogenesis of this heretofore undescribed combination is discussed.

Adenolymphoma↗
PubMed1997

Merkel cell carcinoma and multiple Bowen's disease: incidental association or possible relationship to inorganic arsenic exposure?

An 81-year-old Japanese male was referred to our clinic in 1991 with multiple Bowen's disease. The associated hyperpigmentation of the trunk and extremities and palmoplantar keratotic nodules indicated that he had suffered from chronic arsenic poisoning. Interestingly, he was a native of Namikata in Ehime, Japan, where many residents have suffered from multiple Bowen's disease with internal malignancy. Arsenic exposure was strongly suspected. Two years later, Merkel cell carcinoma developed on the dorsum of his right hand, where Bowen's disease lesions were absent. Metastasis of this Merkel cell carcinoma led to his eventual death one year later. To our knowledge, this is the first report of Merkel cell carcinoma associated with multiple Bowen's disease. Chronic arsenic poisoning may be responsible for the association of these two rare skin neoplasms.

Aged↗
PubMed1986

Merkel cell tumour of the skin.

Two cases of a rare neuroendocrine skin tumour (Merkel cell carcinoma) are reported. The tumour affects mainly old women and men. It has a great tendency to metastasize to lymph nodes and distant sites. The primary treatment is surgical but radiotherapy has an important role to play. Merkel cell tumours are capable of producing NSE and have also been documented to secrete calcitonin and ACTH. Difficulties in histological diagnosis are frequent. The definitive diagnosis can only be made by electron microscopic examination.

Adenocarcinoma↗
PubMed1997

Primary neuroendocrine (merkel cell) carcinoma of the anterior skull base.

A case of a primary neuroendocrine (Merkel cell) carcinoma arising in the anterior skull base involving the dura, both frontal lobes, and the paranasal sinuses is presented. The tumor was completely removed by an enlarged bifrontal transbasal approach. The neuropathological, immunohistological, and electron microscopical investigation revealed all characteristics of a Merkel cell carcinoma, normally presenting as a skin carcinoma of the head and neck. The history, treatment, neuropathology, and possible explanation for this rare manifestation are discussed.

Case Reports↗
PubMed1999

Neuroendocrine (Merkel cell) carcinoma of the oral mucosa: report of a case with immunohistochemical study and review of the literature.

Merkel cell carcinoma (Mcc) is an uncommon and aggressive tumour with neuroendocrine features that occur predominantly in the head and neck region. The rarity of this tumour, especially when it arises in the oral mucosa, makes both early identification and standardisation of treatment difficult, particularly as regards complementary treatment. The availability of monoclonal antibodies with restricted specificity for some antigens thought to be related to neuroendocrine carcinomas, such as Merkel cell carcinoma, and ultrastructural studies offer some new leads to investigation. This has allowed, a greater number of these tumours to be discovered, thereby increasing the chances of effective management. A case of Mcc of the floor of the mouth is reported, together with the results of cytokeratin, neuron specific enolase and chromogranin immunohistochemistry.

Antibodies, Monoclonal↗
PubMed1987

EM diversity of neuroendocrine (Merkel) cells of the human skin.

Ultrastructural differences in size of granules of adjacent Merkel cells belonging to normal skin of three patients are demonstrated. The differences, apparent on simple examination of micrographs, were confirmed using morphometric and statistical analysis. Differences are statistically significant (p less than or equal to 0.001) for maximum diameter and granular area. The existence of a NE (Merkel) cells system or population in the skin similar to that observed in diverse epithelial sheets of the human body, is suggested.

Adult↗
PubMed2002

Alterations of the SDHD gene locus in midgut carcinoids, Merkel cell carcinomas, pheochromocytomas, and abdominal paragangliomas.

Several types of endocrine tumors show frequent somatic deletions of the distal part of chromosome arm 11q, where the tumor-suppressor gene SDHD (succinate-ubiquinone oxidoreductase subunit D), constitutionally mutated in paragangliomas of the head and neck, is located. In this study, we screened 18 midgut carcinoids, 7 Merkel cell carcinomas, 46 adrenal pheochromocytomas (37 sporadic and 9 familial), and 7 abdominal paragangliomas for loss of heterozygosity (LOH) and/or mutations at the SDHD gene locus. LOH was detected in 5 out of 8 (62%) informative midgut carcinoids, in 9 out of 30 (30%) sporadic pheochromocytomas, in none of the familial pheochromocytomas (0%), and in 1 out of 6 (17%) abdominal paragangliomas. No sequence variants were detected in the pheochromocytomas or paragangliomas. However, two constitutional putative missense mutations, H50R and G12S, were detected in two midgut carcinoids, which were both associated with LOH of the other allele. The same sequence variants were also detected in two Merkel cell carcinomas. In addition, the S68S polymorphism was found to coexist with the G12S sequence variant in both cases. In conclusion, we show that alterations of the SDHD gene seem to be involved in the tumorigenesis of both midgut carcinoids and Merkel cell carcinomas.

Abdominal Neoplasms↗
PubMed2006

Adjuvant local irradiation for Merkel cell carcinoma.

OBJECTIVES: To determine the effect of adjuvant local irradiation on (1) disease recurrence and (2) survival rates in Merkel cell carcinoma (MCC). DATA SOURCES: An Ovid MEDLINE search (January 1966-May 26, 2004) was performed using the following criteria: group 1, "Merkel cell OR trabecular OR neuroendocrine skin OR APUDoma skin OR primary small cell skin OR primary undifferentiated skin OR endocrine skin OR neuroepithelial" AND group 2, "carcinoma OR tumor OR cancer" with mapping modifiers "-title, -abstract, -keyword, -subject heading." The search yielded 843 citations. STUDY SELECTION: The Ovid set was then searched using the following criteria: "surgery OR radiation OR radiotherapy," which yielded 242 discrete citations. Reports from all 242 citations were reviewed. For the remaining 601 citations, abstracts (when available) were reviewed to assess the level of relevance for potential inclusion; reports from 63 of these citations were reviewed. An additional 28 secondary references were reviewed, for a total of 333 reports. DATA EXTRACTION: The following criteria for inclusion were applied to each potential patient: (1) a histopathologic diagnosis of MCC; (2) a single, primary tumor arising on the skin, for which (3) the primary treatment was surgical excision (local excision, wide excision, or Mohs surgery) with or without the use of adjuvant irradiation (to the tumor bed); (4) following surgery, negative (clear) surgical margins were obtained; (5) during the postoperative follow-up period, disease recurrence, progression, and survival and/or duration of event-free interval was documented with (6) a minimum follow-up of 1 month. A total of 1254 patients were included in the analysis. RESULTS: Statistically significant reductions in local (hazard ratio [HR], 0.27; P < .001) and regional (HR, 0.34; P < .001) recurrence were observed among patients treated with combination therapy compared with surgery alone. Similar rates of distant metastasis were observed between treatment groups (HR, 0.79; P = .31). Overall survival rates were 87% (1 year) and 49% (5 years). Cause-specific survival rates were 90% (1 year) and 62% (5 year). In general, differences in overall (HR, 0.78; P = .16) and cause-specific (due to MCC: HR, 0.72; P = .14) survival rates between treatment groups did not reach statistical significance. A subgroup analysis that excluded single-patient case reports and studies of only 1 treatment group revealed a significant overall (HR, 0.63; P = .02) and cause-specific (HR, 0.62; P = .04) survival advantage after treatment with combination therapy. CONCLUSIONS: Surgery plus local adjuvant irradiation was associated with significantly lower rates of local and regional recurrence of MCC than surgery alone. Prospective investigation is needed to clarify the presence of a survival benefit from combination therapy.

Adult↗
PubMed1996

[Merkel cell tumor of the hand in a 104-year-old patient. Case report with review of the literature].

Merkel cell tumors represent a rare subepidermal tumor of the skin. Despite the high tumor-mitosis-rate, the survival rate is rather high. This characterizes the biologic behavior of these tumors. We report on a 104-year-old female patient who presented with a histologically proven Merkel cell tumor of the finger existing over a period of more than 15 years. Based on our case report, the specific behavior of these tumors is documented. The pertinent literature is discussed.

Aged↗
PubMed1980

Met-enkephalin-like immuno- and bioreactivity in extracts from skin containing Merkel cells.

Skin from the upper lip, bearing the sinus hair follicles rich in Merkel cells was investigated in guinea pig, rat, cat and rabbit by radioimmunoassay and radioreceptor assay. In all species Met-enkephalin-like immunoreactive material was extracted. In guinea pig this material had the same molecular size as Met-enkephalin. In a radioreceptor assay made with rat brain membranes extracts of guinea pig skin caused displacement of [3H]Met-enkephalin. The endogenous opioid of the size of Met-enkephalin contained in these skin extracts possibly derives from the Merkel cells.

Animals↗
PubMed1994

Merkel cell tumor of the eyelid and the cytologic aspect in fine-needle aspirates: report of a case.

We describe one case of Merkel cell tumor (MCT) of the eyelid diagnosed by fine-needle aspiration (FNA). The main cytologic features were: isolated cells, loose cohesive sheets, and rosette-like structures in a hematic background. The cells were round to ovoid and very uniform. Chromatin was finely granular and frequent mitotic figures were observed. Under close scrutiny small faintly stained juxtanuclear "caps" were seen. A strong dot-like positivity for CK22 and NFP was observed in the position corresponding to the "caps." NSE positivity was diffuse, although a weak dot-like positivity was seen in some cells. S-100 was negative. Both the cytologic features and the immunocytologic profile of Merkel cell tumor are very characteristic. FNA enables an early and confident diagnosis of this aggressive tumor and an early planning of surgery.

Aged↗