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PubMedDate not supplied

Merkel cell carcinoma: Is there a role for 2-deoxy-2-[f-18]fluoro-D-glucose-positron emission tomography/computed tomography?

PURPOSE: 2-Deoxy-2-[F-18]fluoro-D-glucose (FDG)-positron emission tomography (PET)/computed tomography (CT) is becoming widely available as a powerful imaging modality, combining the ability to detect active metabolic processes and their morphologic features in a single study. The role of FDG-PET/CT is proven in lymphoma, melanoma, colorectal carcinoma, and other cancers. However, there are rare malignancies such as Merkel cell carcinoma that can potentially be evaluated with PET/CT. We were therefore prompted to review our experience with FDG-PET/CT in the management of patients with Merkel cell carcinoma. PROCEDURES: This is a retrospective case series of six patients with Merkel cell carcinoma, 58-81 years old (average 69 +/- 8.3), who had whole-body PET/CT at our institution from January 1st, 2003 to August 31st, 2005. Two patients were women and four were men. Reinterpretation of the imaging studies for accuracy and data analysis from medical records were performed. RESULTS: Twelve examinations were acquired for the six patients (one patient had six PET/CT, one patient had two PET/CT, and four patients had one PET/CT). The injected FDG doses ranged 381.1-669.7 MBq (average 573.5 +/- 70.3). Four patients had the PET/CT as part of initial staging, and two patients had the exam for restaging (after surgery and XRT). A total of six Merkel lesions (pancreas, adrenal, lip, submandibular lymph nodes, cervical lymph nodes, and parapharyngeal soft tissue) were identified in three patients and confirmed on histopathological examination. The FDG uptake in these areas was intense, with maximum standardized uptake value (SUVmax) values of 5-14 (average 10.4 +/- 3.8). In one patient, the PET/CT scan identified abnormal focal distal sigmoid uptake that was biopsied and diagnosed as adenocarcinoma. Two patients had negative scans and had no clinical evidence of disease on follow-up office visits (up to one year after PET/CT). CONCLUSIONS: This case series suggests that FDG-PET/CT may have a promising role in the management of patients with Merkel cell carcinoma.

Aged↗
PubMed2000

Merkel cell carcinoma in a renal transplant patient.

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine skin cancer which seems to be common in transplant recipients. We describe the case of a renal transplant patient who developed a MCC on the right glutaeus eight years after transplantation.

Carcinoma, Merkel Cell↗
PubMed1991

Chemotherapy of disseminated Merkel-cell carcinoma.

Six patients developed metastatic merkel-cell carcinoma and were treated with a combination chemotherapy frequently used for small-cell lung cancer. Five of six patients had a complete response for a median of 3.5 months. Overall survival from initiation of chemotherapy was a median of 6.5 months. Two patients died from major complications of therapy.

Adult↗
PubMed1996

Chromosome 6 trisomy as sole anomaly in a primary Merkel cell carcinoma.

We present a case of Merkel cell carcinoma of the thigh diagnosed by conventional histology, immunohistochemistry, electron microscopy and cytogenetics. A unique chromosome 6 trisomy characterized this primary neoplasm, as confirmed by FISH study. The role of chromosome analysis and interphase cytogenetics is emphasized as an adjunct in the subtyping of tumours and their prognostic evaluation.

Aged↗
PubMed2001

Merkel cell carcinoma: an overview and case report.

Merkel cell carcinoma is an extremely rare neoplasm with a high rate of recurrence and metastasis. The lesions predominantly arise on sun-exposed areas of skin in whites between the sixth and seventh decades of life. Within the head and neck region, the cheeks and eyelids are the most common sites. This article outlines the etiology, pathogenesis, and treatment of this rare but highly aggressive tumor.

Aged↗
PubMed1991

Chemotherapy of metastatic Merkel cell cancer.

Out of 16 cases of Merkel cell cancer identified in the records of the Mt. Sinai Medical Center or affiliates, 11 patients developed systemic metastases. Literature review confirms the substantial possibility of dissemination. Both in our series and in the literature, cytotoxic chemotherapy produced a high rate of usually short-lived response, although one of our patients with disseminated metastases achieved complete remission for two years.

Adult↗
PubMed2004

[Merkel cell carcinoma of the head and neck].

Merkel cell carcinoma (MCC) is a skin cancer arising from neurosecretory cells which take part in APUD system. In most cases it is locally growing tumor with significant tendency to local recurrences after surgery. The authors have described four cases MCC localised on the skin of the middle angle of the eye, lower eyelid, auricle and cheek, without nodal metastases. All patients have been surgery treated, in two cases reconstructive surgery was performed. Radiotherapy followed surgery was used for two patients. The authors have reported 5-year survival rate in 2 cases, 2-year disease-free rate and 18 month in other cases.

Aged↗
PubMed1998

Diagnostic pitfalls of Merkel cell carcinoma and dramatic response to chemotherapy.

Merkel cell carcinoma (MCC) is an unusual malignant tumor that arises from neuroendocrine cells with features of epithelial differentiation. We describe a MCC patient with unusual clinical, histopathological, and immunohistochemical features. Although the microscopic, immunohistochemical, and ultrastructural characteristics of MCC have been well defined, diagnostic difficulties remain, particularly in distinguishing it from lymphoma involving the skin, as suggested by our case. This is an unusual case in which dense lymphoid infiltration masked the true tumor. All the immunohistochemical markers of MCC except neuron-specific enolase (NSE) were negative. The dramatic response to primary chemotherapy was also very noteworthy.

Adult↗
PubMed2006

[Merkel cell carcinoma of the upper lid].

AIMS: Merkel cell carcinoma (MCC) of the skin is a rare form of cutaneous malignancy of neuroendocrine origin with a propensity to form cutaneous and lymphogenous metastases. The tumor, affecting predominately elderly patients, has a significantly higher incidence in female patients (80%) compared to male patients (20%). The mainstay of therapy is surgical resection with possible adjuvant radio- or chemotherapy. CASE REPORT: A case of a 78-year-old patient with a MCC of the upper lid without lymph node involvement or distant metastasis is described. The tumor was resected and the defect closed by a temporal skin flap performing a temporary cantholysis. The clinical follow-up revealed an undisturbed eye lid function without any clinical or radiological signs of a locoregional or distant recurrence.

Aged↗
PubMed1987

[Neuroendocrine carcinoma (Merkel cell tumor) in the head and neck area].

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.

Aged↗
PubMed2003

Epidemiology of primary Merkel cell carcinoma in the United States.

BACKGROUND: Merkel cell carcinoma (MCC) is a rare, aggressive skin cancer. OBJECTIVE: We sought to describe primary MCC incidence trends, epidemiology, and predictors of survival. METHODS: The population covered by the Surveillance, Epidemiology, and End Results Program was analyzed as a prospective cohort. We measured age-adjusted incidence rates (per 100,000 person-years) and effect of age, anatomic site, and stage on survival. RESULTS: Incidence was higher in males (0.34) than in females (0.17). Cases (n = 1034) occurred mostly in whites (94%), in people older than 65 years (76%), and at the head (48%). The 5-year relative survival was 75%, 59%, and 25% for localized, regional, and distant MCC, respectively. Female sex, limb presentation, localized disease, and younger age were positive predictors of survival. CONCLUSION: The highest incidence of MCC was observed in whites, males, and in people older than 65 years. Only 49% of cases were reported as localized. Better survival was associated with limb localization, early-stage disease, younger age, and female sex.

Adolescent↗
PubMed2000

The Merkel cell carcinoma: survival and oncogene markers.

BACKGROUND: Merkel cell carcinoma (MCC) is a rare and malignant tumour. Survival data and prognostic factors are scarce. AIM: To investigate the usefulness of biological markers to predict the prognosis for these aggressive tumours. METHODS: C-myc oncoprotein and proliferation was analysed in specimens from 13 patients with MCC, treated between 1983 and 1997. The average age at presentation was 68.3 years. Overall follow-up ranged from 14 to 158 months, with a mean of 68.2 months. Specimens were analysed by immunohistochemistry for proliferation (mib-1) and flow cytometry for oncogene activity (c-myc). RESULTS: The median positivity was 52% for the c-myc oncogene and 50% for proliferation, but these did not correlate to survival as analysed by the Kaplan-Meier method. Other parameters such as median age at presentation, sex, site of tumour and adjuvant radiotherapy were also analysed, but none were found to be significant. CONCLUSIONS: This study showed that neither c-myc oncogene activity or mitotic index in MCC can be related to patient survival.

Aged↗
PubMedDate not supplied

Management of Merkel cell carcinoma: case series of 36 patients.

Merkel cell carcinoma is a rare, highly malignant skin tumor with a predisposition for local, nodal and distant recurrence which should be managed in a multimodal approach. Here, we performed a retrospective analysis of 36 patients, treated from 1984 to 1994. In patients with stage I disease, locoregional recurrence after surgery alone occurred in 65% compared to 43% after excision and adjuvant radiotherapy. Although the difference in disease-specific survival was not significant (67% versus 52% at 5 years), combination therapy conferred a benefit for locoregional control and relapse-free survival (88 versus 58 months). The majority of failures (54%) occurred within the draining lymph nodes that were not treated in the initial approach and locoregional recurrence was strongly associated with a later systemic relapse (50% versus 0%). Salvage after localized recurrence was achieved in 67% of resectable cases. The high rate of nodal recurrence after surgery alone warrants the use of elective nodal treatment in patients with stage I disease. Surgical resection of the primary tumor should be followed by postoperative radiotherapy to the primary site and draining lymph nodes. Even after locoregional recurrence, a substantial proportion of patients is able to achieve long-term disease-free survival, particularly after complete resection and adjuvant irradiation.

Adult↗
PubMedDate not supplied

[Role of lymphadenectomy in the treatment of Merkel-cell tumors in i and ii stages].

Merkel cell carcinoma (MCC) is a rare, malignant skin cancer, exhibiting neuroendocrine differentiation, with a significant incidence of locoregional lymph nodal involvement (40%-73%). The accepted staging system classifies MCC as: stage I, localized skin disease; stage II, regional lymph node disease; stage III, metastatic disease. The clinical differentiation of stage I and II patients is difficult and understaging is frequent. Surgery, as first approach, represents the leading treatment for this neoplasm and, depending on stage consists in: local wide excision for stage I patients and local excision and lymphadenectomy for stage II. In our experience, lymphadenectomy, included in the initial treatment of all stage II patients, seemed to influence positively the prognosis. In comparing stage related recurrence and survival rates the results we obtained were better in stage II patients, where lymphadenectomy was included in the initial treatment than in stage I subjects, who received local excision alone as first treatment and lymphadenectomy as secondary treatment for nodal recurrence (overall recurrence rate 86% vs 20%, survival rate 71% vs 80% in stage I vs stage II patients). The performance of lymphadenectomy for stage I MCC could be reconsidered both for a more reliable staging of the disease and for a positive impact on recurrence and survival rates.

Carcinoma, Merkel Cell↗
PubMed2004

Merkel cell carcinoma of the head and neck.

Merkel cell carcinoma (MCC) is a rare neuroendocrine neoplasm of the skin. The tumor most frequently affects elderly patients, with a preference for the head and neck. Incidence rates increase with sun exposure and after immunosuppression and organ transplantation. A significant proportion of MCC have been reported to occur in intimate association with malignant epithelial neoplasms. The genetic mechanisms underlying the development and tumor progression of MCC are poorly understood, sharing pathogenetic mechanisms with other neoplasms of neural crest derivation. MCC has a propensity for spreading to regional lymph nodes, either at presentation or as a first site of relapse. Sentinel lymph node positivity is helpful in predicting the risk of recurrence or metastasis in patients with MCC. Complete surgical resection is the mainstay of treatment of the primary tumor. Tumor resections are recommended to include a 2-3-cm tumor-free margin around the primary lesion when possible, but this is often difficult to achieve in the head and neck, where Mohs micrographic surgery has proved to be effective. The role of adjuvant radiation therapy is controversial. The role of adjuvant chemotherapy in diminishing the risk of subsequent systemic recurrence in patients with positive nodes remains undefined. Overall response rates to combination chemotherapy for surgically unresectable distant metastatic disease are generally high, although responses are transient. Overall survival of head and neck MCC at 5 years postoperatively ranks between 40% and 68%. MCC has a high incidence of locoregional recurrences, but even after a locoregional failure, a substantial proportion of patients achieve long-term disease-free survival. Finally, factors generally associated with survival are the stage of disease at presentation, distant recurrence usually being the most adverse predictor of survival.

Carcinoma, Merkel Cell↗
PubMed2001

Merkel cell carcinoma: squamous and atypical fibroxanthoma-like differentiation in successive local tumor recurrences.

Merkel cell carcinoma (MCC) is a rare, frequently lethal, primary neuroendocrine carcinoma of the skin. Histopathologically, it appears as a dermal nodule of small, undifferentiated malignant cells. Historically, MCC was considered to be an eccrine carcinoma. Recognition of its neuroendocrine features later led to the hypothesis that it arose from Merkel cells in the skin, although recent evidence revisits the question of an epithelial origin. We present a case of MCC arising on the temple of a 78-year-old male, in association with an actinic keratosis. Three years later, a local tumor recurrence showed a mixed malignancy comprising small cell neuroendocrine and large cell squamoid components. A further recurrence at the site two years later, after local radiotherapy, revealed a bizarre pleomorphic large cell morphology with retention of immunohistochemical features of a neuroendocrine carcinoma. Evolution to a bizarre pleomorphic large cell neoplasm has been recorded in malignant tumors treated by radiotherapy, but is unique for MCC. The association of this MCC with an actinic keratosis and the development of squamoid differentiation in a local recurrence support the link between MCC and epithelial neoplasia. In addition, its evolution to an atypical fibroxanthoma-like morphology is of interest, because some view atypical fibroxanthomas as bizarre variants of squamous cell carcinoma.

Aged↗
PubMed1987

Disseminated Merkel cell tumor. Treatment with systemic chemotherapy.

Four patients with disseminated Merkel cell tumors were treated with cyclophosphamide (C), doxorubicin (A), and vincristine (V). Two partial responses (PR) were noted and in one case disease remained stable. One of the patients who achieved a PR achieved a second PR when treated with VP-16 (E) and cis-platin (P) after progressive disease developed. Systemic chemotherapy appears capable of inducing objective responses in some patients with disseminated Merkel cell tumors.

Antineoplastic Combined Chemotherapy Protocols↗
PubMed1996

Proliferative Merkel cells were not detected in human skin.

The fetal development of Merkel cells-neuroendocrine cells of the skin - has been a matter of debate for a long time. Recent results have helped to confirm their intraepidermal development in humans. Simple epithelial cytokeratins (CK) nos. 8, 18, 19 and 20 are well established markers at the light microscopic level. These cells could be detected from fetal week 8 within the epidermis with an enormous increase during the following weeks. This gives rise to the question as to whether Merkel cells are undergoing mitoses or whether they are derived from basal keratinocytes. We studied fetal and adult skin using antibodies to simple epithelial CK and to Ki67, a human nuclear cell proliferation-associated antigen in an attempt to answer these questions. In human adult and fetal skin of various stages we could not detect any Merkel cells undergoing cell division. These results suggest that Merkel cells are postmitotic cells to be renewed from undifferentiated keratinocytes with stem cell characteristics.

Adult↗