Merkel-cell carcinoma of the skin

Recurrent Merkel Cell Carcinoma Following COVID-19 Treatment

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine skin cancer influenced by the immune system. Recent studies suggest that viral infections, notably COVID-19, may exacerbate such malignancies. This case report explores potential mechanisms by which SARS-CoV-2, the virus responsible for COVID-19, could influence the behavior and proliferation of malignant tumor cells. Emerging evidence indicates that COVID-19 may disrupt immune surveillance and modulation, which are critical in controlling the spread and severity of cancers, including MCC. Additionally, the cytokine storm induced by COVID-19 is proposed to facilitate tumorigenic activity, potentially enhancing MCC aggressiveness. By integrating clinical findings with contemporary immunological and virological theories, this report aims to contribute to the understanding of COVID-19's impact on cancer progression, specifically MCC, emphasizing the need for comprehensive management strategies in cancer patients during the pandemic.

Merkel-cell carcinoma: ESMO-EURACAN Clinical Practice Guideline for diagnosis, treatment and follow-up

•This ESMO Clinical Practice Guideline provides key recommendations for managing Merkel-cell carcinoma (MCC). •Recommendations are based on available scientific data and the multidisciplinary group of experts’ collective opinion. •The guideline covers clinical and pathological diagnosis, staging and risk assessment, treatment and follow-up. •Algorithms for the management of locoregional and inoperable/metastatic disease are provided. •A multidisciplinary team with a high level of expertise in MCC should diagnose and make decisions about therapy.

Neoplasms of the Ear Canal

Primary EAC neoplasms include benign and malignant lesions of bony, glandular or cutaneous origin. Small, benign slow growing bony neoplasms are often asymptomatic, diagnosed incidentally and might not require intervention. Both malignant and benign neoplasms of cutaneous and glandular origin can present with symptoms of chronic otitis externa, leading to delays in diagnosis. Prompt biopsy of soft tissue lesions associated with non-resolving otitis externa are warranted. Local and regional imaging is helpful to understand disease extent and origin, but even early-stage malignant neoplasms require aggressive surgical treatment.

Merkel Cell Carcinoma in an Elderly Male With Extensive Local Disease

Merkel cell carcinoma (MCC) is a rare, highly aggressive neuroendocrine carcinoma of the skin. It is often found in the sun-exposed skin areas of elderly individuals of Caucasian descent. MCC has a tendency for local recurrence and the potential to invade nearby lymph nodes and spread to distant sites in the body. Here, we present the case of an 83-year-old male with a history of multiple comorbidities, including congestive heart failure, obesity, hypertension, benign prostatic hyperplasia, and sarcoidosis, who presented with a slow-growing, fungating lesion on his left lower leg. Histopathological examination revealed MCC with extensive necrosis and involved resection margins. Additional skin lesions on the left knee were confirmed to be MCC. Follow-up CT scans showed lymphadenopathy and a femoral lesion. The patient was deemed a poor candidate for resection and placed on immunotherapy treatment. The low incidence rate and indistinct clinical manifestations of MCC make a conclusive diagnosis dependent on examining histological features and immunohistochemical markers through a lesioned biopsy or resection. Due to the aggressive nature of MCC and the tendency for asymptomatic and painless lesions to escape notice, it is important to raise awareness about this condition. This will lead to earlier detection and intervention, potentially enhancing patient survival rates.

Intestinal obstruction due to small intestinal metastasis from primary Merkel cell carcinoma of the gluteal region

Merkel cell carcinoma (MCC) is a rare neoplasm of unknown multifactorial origin first described in 1972. It occurs most often in older Caucasian males and is typically associated with sun-exposed areas of skin. However, cases have also been reported in other areas, such as the trunk and the gluteal region. Metastatic disease will occur in up to one-third of cases at onset or during the course of the disease, including metastases to the abdominal organs. We present the case of a 53-year-old male with a history of primary MCC of the right buttock and local resection surgery. Eighteen months later, he presented with a small bowel obstruction and had an emergency segmental bowel resection. Pathology examination with immunohistochemistry concluded that findings were consistent with metastatic MCC.

Merkel cell polyomavirus and associated Merkel cell carcinoma

Merkel cell polyomavirus (MCPyV) is a ubiquitous skin infection that can cause Merkel cell carcinoma (MCC), a highly lethal form of skin cancer with a nearly 50% mortality rate. Since the discovery of MCPyV in 2008, great advances have been made to improve our understanding of how the viral encoded oncoproteins contribute to MCC oncogenesis. However, our knowledge of the MCPyV infectious life cycle and its oncogenic mechanisms are still incomplete. The incidence of MCC has tripled over the past two decades, but effective treatments are lacking. Only recently have there been major victories in combatting metastatic MCC with the application of PD-1 immune checkpoint blockade. Still, these immune-based therapies are not ideal for patients with a medical need to maintain systemic immune suppression. As such, a better understanding of MCPyV's oncogenic mechanisms is needed in order to develop more effective and targeted therapies against virus-associated MCC. In this review, we discuss current areas of interest for MCPyV and MCC research and the progress made in elucidating both the natural host of MCPyV infection and the cell of origin for MCC. We also highlight the remaining gaps in our knowledge on the transcriptional regulation of MCPyV, which may be key to understanding and targeting viral oncogenesis for developing future therapies.

Merkel cell carcinoma: A systematic review of the demographic and clinical characteristics of 847 cases in Japan

Merkel cell carcinoma (MCC) is a rare but aggressive neuroendocrine carcinoma of the skin associated with Merkel cell polyomavirus and immunosuppression. Although MCC incidence is rising worldwide, MCC has not been sufficiently investigated in Japan. This study aimed to determine MCC demographics in Japan, including incidence, age, sex, location, spontaneous regression, and pure/combined MCC. Using PubMed and Igaku Chuo Zasshi, 847 MCC cases between 1985 and 2015 were extracted, and the main epidemiological characteristics were described. The mean age of all patients was 77.5 years. Regarding the characterized lesions, 63.0% were located on the head and neck, 5.2% on the trunk, 12.6% on the upper limb, 15.1% on the lower limb, 3.5% on the buttocks, and 0.6% on the genitals. Histopathological information regarding the presence of other malignancies could be retrieved in 611 cases, and a coexisting malignancy, mainly squamous cell carcinoma and Bowen's disease, was present in 14.2%. Subcutaneous MCC was observed in 31 patients with a male : female ratio of 1.07 (16 men/15 women). Nodal lesions with unknown primary tumor location were described in 19 patients with a male : female ratio of 0.9 (nine men/10 women) and a mean age of 77.7 years. Of 640 evaluable cases, spontaneous regression developed in 9.1%. Among those 58 patients, the male : female ratio was 1:2.1 in 56 evaluable cases (18 men/38 women). Merkel cell polyomavirus was assessed in 180 patients, and the virus was detected in 31.1% and not detected in 68.9% of the patients. MCC is a rare disease in Japan, with incidence rates and male : female ratios differing from those in the USA and European countries. Besides, this study reveals the high frequency of subcutaneous MCC and MCC with divergent differentiation patterns and spontaneous regression in Japan compared to other countries.

Multidisciplinary team approach for Merkel cell carcinoma: the European Institute of Oncology experience with focus on radiotherapy

OBJECTIVE

To review the therapeutic strategy in Merkel cell carcinoma (MCC) treated with radiotherapy (RT) discussed in a multidisciplinary tumour board.

METHODS

Clinical records of patients with a diagnosis of MCC and with an indication to undergo RT at the European Institute of Oncology between 2003 and 2018 were reviewed retrospectively.

RESULTS

Twenty-six patients were included in the analysis (median age 65 years, range 42-87). Nineteen received adjuvant RT, 4 exclusive RT, and the remainder palliative RT. Intensity-modulated RT was used in 13 cases, a 3D conformal technique in 11 cases, and stereotactic RT in 2 cases. No major toxicities were recorded. The median relapse-free survival (RFS) after adjuvant RT was 20.5 months, while for unknown primary MCC, it was 23 months. In the adjuvant setting, median polyomavirus-positive RFS was 21.5 months (range 1-49) and median polyomavirus-negative RFS was only 14 months (range 4-45). Overall, RFS of polyomavirus-positive and polyomavirus-negative patients was 10.5 and 8 months, respectively. After adjuvant RT, only 1 out of 10 patients had a recurrence in the RT field. At the time of data collection, 16 patients were alive with no evidence of disease, 1 patient was alive with advanced status of disease, 8 patients died of disease progression, and 1 patient died of other causes.

CONCLUSIONS

The management of unknown primary and polyomavirus-positive cases, which had a better prognosis in our series, may benefit from a multidisciplinary approach, given the limited data available regarding optimal treatment.

Merkel cell carcinoma

Merkel cell carcinoma (MCC) of the skin is a rare, aggressive form of skin cancer that metastasizes to other parts of the body. This cutaneous neuroendocrine tumour mainly affects older people, with most cases generally occurring over the age of 50 years. Merkel cell polyomavirus has been shown to induce gene mutations resulting in this skin cancer, with immunosuppression and ultraviolet radiation being other key risk factors in its pathogenesis. MCC is clinically seen as a rapidly enlarging, isolated, irregular erythematous nodule typically found on sun-exposed sites. Diagnosis is through clinical examination followed by tissue biopsy, which demonstrates characteristic histopathological neuroendocrine features. Immunohistochemistry plays a crucial role in diagnosis with the characteristic perinuclear staining with cytokeratin-20 helping to differentiate it from other morphologically similar tumours. Sentinel lymph node biopsy and imaging is essential for staging and determining prognosis. Surgical excision is the mainstay of treatment for localized disease although adjuvant radiotherapy is often required. Metastatic disease involves a very poor prognosis, and immune checkpoint inhibitors have recently shown promise in the treatment of metastatic disease. Avelumab, a monoclonal antibody that binds to the programmed death-1 receptor, has been approved by the National Institute for Health and Care Excellence and shown encouraging survival outcomes. It provides an option for treating metastatic carcinoma in adults after they have failed ≥ 1 line of chemotherapy for metastatic disease.

Combined radio-immunotherapy leads to complete clinical regression of stage IV Merkel cell carcinoma

Merkel cell carcinoma (MCC) is a rare, aggressive neuroendocrine tumour of the skin. While localised disease carries an overall favourable prognosis, metastatic disease is associated with poor clincal outcomes. Most cases of metastatic MCC are managed with systemic chemotherapy or immunotherapy, though 5-year survival for these patients remains a dismal 17%. Here, we present the case of a 79-year-old man with MCC of the right ear with metastases to regional lymph nodes, ipsilateral parotid gland and thoracic spine. He was treated with a combination of first-line radiotherapy and concurrent immune checkpoint inhibition (avelumab), which led to complete clinical regression of disease with minimal adverse effects. This observation suggests that combined radio-immunotherapy warrants larger-scale investigation for use in patients with unresectable MCC.

CCL17/TARC and CCR4 expression in Merkel cell carcinoma

Merkel cell carcinoma (MCC) is a rare, highly aggressive neuroendocrine skin cancer. In more than 80% of the cases, Merkel cell polyomavirus (MCPyV) is a causal factor. The oncogenic potential of MCPyV is mediated through its viral oncoproteins, large T antigen (LT) and small t antigen (sT). To investigate the role of cytokines in MCC, a PCR array analysis for genes encoding inflammatory cytokines and receptors was performed on MCPyV-negative and MCPyV-positive MCC cell lines, respectively. We detected an increased expression of CCL17/TARC in the MCPyV-positive MKL2 cell line compared to the MCPyV-negative MCC13 cell line. Transfection studies in MCC13 cells with LT expression plasmid, and a luciferase reporter plasmid containing the CCL17/TARC promoter, exhibited stimulated promoter activity. Interestingly, the ectopic expression of CCL17/TARC upregulated MCPyV early and late promoter activities in MCC13 cells. Furthermore, recombinant CCL17/TARC activated both the mitogen-activated protein kinase and the NF-κB pathways. Finally, immunohistochemical staining on human MCC tissues showed a strong staining of CCL17/TARC and its receptor CCR4 in both LT-positive and -negative MCC. Taken together, CCL17/TARC and CCR4 may be a potential target in MCC therapy providing MCC patients with a better overall survival outcome.

Lymph Node Metastases of Merkel Cell Carcinoma from Unknown Primary Site: Report of Three Cases

Merkel cell carcinoma (MCC) is an uncommon aggressive neuroendocrine skin carcinoma. It usually affects sun-exposed skin of white elderly people. MCC is characterized by a high incidence of early locoregional relapse and distant metastases. Because of its rarity and the resulting lack of prospective randomized trials, data regarding the optimal treatment of MCC are limited. Despite aggressive multimodality treatment, the prognosis of patients bearing MCC is often poor. We report three cases of lymph node metastases of MCC with unknown primary sites. Two patients died 17 and 28 months after diagnosis due to brain and pancreatic metastases, respectively, without evidence of cutaneous disease. The third patient is alive and free of tumor at 16 months from the diagnosis. After an accurate diagnosis of lymph node metastases from MCC, the absence of a primary tumor at complete initial evaluation and during adequate follow-up can confirm this particular clinical scenario. The prognosis seems to be analogous to that of cases with similar disease stage (lymph node involvement) but a known primary site.

Efficacy of isolated limb perfusion (ILP) in patients with Merkel cell carcinoma (MCC): A multicenter experience

BACKGROUND

Merkel cell carcinoma (MCC) is a rare and potentially aggressive neuroendocrine tumor of the skin, with a propensity for locoregional metastases. In two expert referral centers, isolated limb perfusion (ILP) is used to obtain locoregional control in selected locoregionally advanced MCC patients. This study describes our experience.

METHOD

Patients who underwent ILP for MCC were analyzed. ILP was performed with melphalan and tumor necrosis factor (TNF) combination therapy. Depending on the institution, either a normothermic or a hyperthermic temperature regimen was used. Baseline characteristics, toxicity data, locoregional progression-free survival (LPFS) and overall survival (OS) were assessed.

RESULTS

Four males and 6 females with a median age of 78 years (IQR 61-84 years) were included. Four patients underwent ILP for upper extremity disease and 6 for lower extremity disease. All patients received combination therapy with Melphalan and TNF, one patient with the addition of interferon-gamma. No signs of systemic toxicity were present post-ILP. Severe locoregional toxicity (compartment syndrome) occurred in 1 patient and 1 elderly patient with extensive atherosclerosis had to undergo transfemoral amputation due to critical ischemia. Eight patients could be included for response evaluation. The overall response rate (ORR) was 87.5% with a complete response (CR) rate of 62.5%. Two long-term responses of 53 months and 71 months were observed. Median LPFS was 5 months and median OS was 54 months.

CONCLUSION

ILP shows a high CR rate that can be durable. Therefore, ILP should be considered an effective treatment modality for locally advanced MCC.

Prognostic factors in Merkel cell carcinoma patients undergoing sentinel node biopsy

INTRODUCTION

Debate remains about prognostic factors in primary Merkel cell carcinoma (MCC). We investigated clinicopathological factors as determinants of survival in patients with MCC submitted to sentinel node biopsy.

METHODS

Sixty-four consecutive patients treated for a primary MCC were identified from a prospectively maintained database at Fondazione IRCCS Istituto Nazionale dei Tumori, Milan. Time to events outcome were described by product limit estimators and proportional hazards model was used to investigate the association between outcome and potential predictors.

RESULTS

The most common site of primary tumor was lower limbs (56.3%). The size of primary lesion was ≤2 cm in 67.2% of cases. Presence of residual disease after the diagnostic surgical excision was observed in 28% of cases. All patients received sentinel node biopsy (SNB) and a SN positivity was detected in 26.6%. The median follow up was 78 months. Disease recurrence occurred in 17 patients (26.6%). In the SN negative group 10 recurrences occurred (21.3%), whereas 7 (41.2%) were found in SN positive one. Nine patients SN negative (19.1%) died of disease and 3 (17.6%) among SN positive. SN status was not associated with survival (p = 0.78). Neither age, gender, size and site of primary tumor resulted predictors of patients' outcome. The presence of residual tumor in the specimen of the wide local excision, after the diagnostic surgical excision, was the only variable associated with survival (p = 0.03).

CONCLUSIONS

Presence of residual tumor in the specimen of the wide local excision is the main prognostic factor in MCC patients.

[Care of Merkel cell carcinoma and role of the radiotherapy]

Merkel cell carcinoma is a rare neuro-endocrine tumor of skin with a poor prognosis. Data available in literature are scarce. Current treatment for locoregional disease is based on combined treatment by surgery and radiotherapy. However these treatments are controversial. The aim of the present review is to sum up the different available studies and to compare national and international guidelines.

Palliative radiotherapy for Merkel cell carcinoma: single-centre experience and review of the literature

Background and purpose

Merkel cell carcinoma is a rare and aggressive primary cutaneous neuroendocrine carcinoma with a high risk of loco-regional and distant metastasis. It is predominantly seen in the elderly, on the head and neck or extremities. Although treated primarily with surgery, some patients are too frail. A World Health Organization performance status of two or more with co-existing medical co-morbidities, or the site of the disease adjacent to a critical structure, can prevent surgical management. In this cohort of patients, primary palliative radiotherapy has been found to achieve excellent tumour regression and improve quality of life. A new palliative split-course hypofractionated regime has been used in North Middlesex University Hospital in this cohort of patients. The purpose of this case series was to provide supporting evidence on the efficacy of this dose and fractionation regime and review the literature for the palliative management of Merkel cell carcinoma.

Materials and methods

In total, four patients were treated with the palliative split-course hypofractionated regime. The regime consisted of an initial 20 Gray in 5 fractions over 1 week, a 2-week gap and then a further 20 Gray in 5 fractions over 1 week. Tolerability and response to treatment were evaluated by history and clinical examination.

Results and conclusion

The split-course hypofractionated regime was well tolerated, achieved excellent tumour regression and improved quality of life in all four patients. Since then, a further three patients have been successfully treated with the above regime. This case series demonstrates the efficacy of this dose and fractionation in a select group of patients too frail for radical management and adds to the evidence base for the optimal palliative management of Merkel cell carcinoma.

Merkel cell carcinoma of unknown primary with lymph node and mesenteric metastasis involving the pancreas and duodenum

Merkel cell carcinoma (MCC) of skin is a rare, aggressive cutaneous malignancy of neuroendocrine origin. MCC predominantly affects elderly Caucasians and has high predilection for sun exposed areas. Histologic exam and immunohistochemical profile is required to establish the diagnosis. It has high propensity for local recurrence and metastasis, and carries poor prognosis. However, metastasis to mesentery involving the duodenum is very uncommon and rarely reported in literature. We hereby describe a patient with lymph node and mesenteric metastasis invading duodenum and pancreas with unknown primary origin of MCC.

ABCB5-Targeted Chemoresistance Reversal Inhibits Merkel Cell Carcinoma Growth

Merkel cell carcinoma (MCC) is a highly aggressive neuroendocrine skin cancer with profound but poorly understood resistance to chemotherapy, which poses a significant barrier to clinical MCC treatment. Here we show that ATP-binding cassette member B5 (ABCB5) confers resistance to standard-of-care MCC chemotherapeutic agents and provide proof-of-principle that ABCB5 blockade can inhibit human MCC tumor growth through sensitization to drug-induced cell cytotoxicity. ABCB5 expression was detected in both established MCC lines and clinical MCC specimens at levels significantly higher than those in normal skin. Carboplatin- and etoposide-resistant MCC cell lines exhibited increased expression of ABCB5, along with enhanced ABCB1 and ABCC3 transcript expression. ABCB5-expressing MCC cells in heterogeneous cancers preferentially survived treatment with carboplatin and etoposide in vitro and in human MCC xenograft-bearing mice in vivo. Moreover, patients with MCC also exhibited enhanced ABCB5 positivity after carboplatin- and etoposide-based chemotherapy, pointing to clinical significance of this chemoresistance mechanism. Importantly, ABCB5 blockade reversed MCC drug resistance and impaired tumor growth in xenotransplantation models in vivo. Our results establish ABCB5 as a chemoresistance mechanism in MCC and suggest utility of this molecular target for improved MCC therapy.

Merkel Cell Carcinoma: When Does Size Matter for Radiotherapy?

Merkel cell carcinoma is a very aggressive, rare cancer of the skin. It has a high propensity for local, regional, and distant recurrence and has recently been associated with a viral etiology from the recently diagnosed Merkel Cell Polyoma Virus. The optimal management remains controversial. We discuss the case of a man with a 26 cm axillary lymph node metastasis of unknown primary treated with radiotherapy.

Merkel cell carcinoma: An algorithm for multidisciplinary management and decision-making

Merkel cell carcinoma (MCC) is a rare and aggressive neuroendocrine tumor of the skin. Therapeutic approach is often unclear, and considerable controversy exists regarding MCC pathogenesis and optimal management. Due to its rising incidence and poor prognosis, it is imperative to establish the optimal therapy for both the tumor and the lymph node basin, and for treatment to include sentinel node biopsy. Sentinel node biopsy is currently the most consistent predictor of survival for MCC patients, although there are conflicting views and a lack of awareness regarding node management. Tumor and node management involve different specialists, and their respective decisions and interventions are interrelated. No effective systemic treatment has been made available to date, and therefore patients continue to experience distant failure, often without local failure. This review aims to improve multidisciplinary decision-making by presenting scientific evidence of the contributions of each team member implicated in MCC management. Following this review of previously published research, the authors conclude that multidisciplinary team management is beneficial for care, and propose a multidisciplinary decision algorithm for managing this tumor.

Modeling a superficial radiotherapy X-ray source for relative dose calculations

The purpose of this study was to empirically characterize and validate a kilovoltage (kV) X‐ray beam source model of a superficial X‐ray unit for relative dose calculations in water and assess the accuracy of the British Journal of Radiology Supplement 25 (BJR 25) percentage depth dose (PDD) data. We measured central axis PDDs and dose profiles using an Xstrahl 150 X‐ray system. We also compared the measured and calculated PDDs to those in the BJR 25. The Xstrahl source was modeled as an effective point source with varying spatial fluence and spectra. In‐air ionization chamber measurements were made along the x‐ and y‐axes of the X‐ray beam to derive the spatial fluence and half‐value layer (HVL) measurements were made to derive the spatially varying spectra. This beam characterization and resulting source model was used as input for our in‐house dose calculation software (kVDoseCalc) to compute radiation dose at points of interest (POIs). The PDDs and dose profiles were measured using 2, 5, and 15 cm cone sizes at 80, 120, 140, and 150 kVp energies in a scanning water phantom using IBA Farmer‐type ionization chambers of volumes 0.65 and 0.13 cc, respectively. The percent difference in the computed PDDs compared with our measurements range from −4.8% to 4.8%, with an overall mean percent difference and standard deviation of 1.5% and 0.7%, respectively. The percent difference between our PDD measurements and those from BJR 25 range from −14.0% to 15.7%, with an overall mean percent difference and standard deviation of 4.9% and 2.1%, respectively — showing that the measurements are in much better agreement with kVDoseCalc than BJR 25. The range in percent difference between kVDoseCalc and measurement for profiles was −5.9% to 5.9%, with an overall mean percent difference and standard deviation of 1.4% and 1.4%, respectively. The results demonstrate that our empirically based X‐ray source modeling approach for superficial X‐ray therapy can be used to accurately compute relative dose in a homogeneous water‐equivalent medium. They also show limitations in the accuracy of the BJR 25 PDD data.

PACS number: 87.55.kh

Merkel cell carcinoma in the left groin: A case report and review of the literature

Merkel cell carcinoma (MCC) is a relatively rare but aggressive primary neuroendocrine carcinoma of the skin. MCC frequently occurs on sun-exposed areas in elderly Caucasian patients and has a propensity for local recurrence, regional lymph node invasion and distant metastases. However, MCC occurring on sites that are not sun-exposed in Asian patients is extremely uncommon. The current study describes the case of a 66-year-old Chinese male who presented with an asymptomatic, smooth lesion in the left inguinal region, which was initially diagnosed as a malignant lymphoma. Upon histological and immunohistochemical analysis, the tumor was consistent with the diagnosis of an MCC. In conclusion, due to its low incidence rate and lack of characteristic clinical manifestations, the final diagnosis of MCC relies on the analysis of histological findings and immunohistochemical markers following lesion biopsy or resection. The present study aimed to report a case of MCC and present a brief literature review in order to bring attention to the diagnosis of this condition.

Risk of second cancers in merkel cell carcinoma: a meta-analysis of population based cohort studies

The risk of second cancers in Merkel cell carcinoma (MCC) remains uncertain since risk estimates vary worldwide. The global MCC population is growing and there is a demand for better knowledge of prognosis of this disease. The Cochrane Database of Systematic Reviews, MEDLINE, and EMBASE search engines were searched for the relevant literature between January 1999 and September 2014 by use of explicit search criteria. The main outcome was second malignancies associated with MCC patients measured by standardized incidence ratios (SIRs) or other estimates of risks. Five papers fulfilled the inclusion criteria and reported SIRs of second cancer in MCC which varied from 1.07 to 2.80. Performing meta-analysis using random effects model revealed that there was an increased risk for second malignancies due to MCC (SIR, 1.52; 95% CI, 1.10–2.11). There was a significant increase in risk for malignant melanoma (SIR, 3.09; 95% CI, 2.02–4.73) as compared to all common second malignancies among the studies. Updated knowledge about risk of second malignancies in MCC will help in better assessment of the disease prognosis and will help in optimizing the medical and surgical treatment, radiotherapy, follow-up, and surveillance procedures.

Small cell carcinoma in the parotid harboring Merkel cell polyomavirus

OBJECTIVE

This study aimed to document three new cases of primary small cell carcinoma (SmCC) of the parotid and examine immunohistochemical and quantitative real-time polymerase chain reaction (qPCR) data of the recently developed Merkel cell polyomavirus (MCPyV) within these tumors.

STUDY DESIGN

Immunohistochemistry for neuroendocrine markers (chromogranin A, CD56, CD57, neuron-specific enolase [NSE], thyroid transcription factor 1 [TTF-1]), epithelial markers (CK20, CK7, CAM 5.2), and MCPyV large T antigen (LTAg) were examined. qPCR and Sanger sequencing were performed to confirm the presence of the MCPyV LTAg gene.

RESULTS

Two males and one female, average age 76 years, presented with left parotid masses. Clinical examinations, histories, and imaging studies were negative for cutaneous Merkel cell carcinoma (MCC), pulmonary and extrapulmonary SmCC, or any other malignancy. Immunohistochemical analysis demonstrated positive immunoreactivity for CK20 in a perinuclear dotlike pattern (3/3), CAM 5.2 (3/3), (2/3), NSE (3/3), CD56 (2/3), and CD57 (3/3). Two cases stained positive for MCPyV, showing moderate to strong, diffuse positivity, confirmed with qPCR. PCR-Sanger sequencing of LTAg exon 2 showed greater than 97% similarity to the MCPyV reference genome in both cases.

CONCLUSION

Our findings expand the number of reported cases classified as primary parotid SmCC that harbors MCPyV and underscore the similarity between cutaneous MCC and parotid SmCC. Further investigation is needed to determine whether immune-based therapeutic strategies targeting MCPyV in MCC are also effective in the setting of parotid SmCC harboring MCPyV.

Molecular pathology of skin neoplasms of the head and neck

CONTEXT

Skin neoplasms include the most common malignancies affecting humans. Many show an ultraviolet (UV)-induced pathogenesis and often affect the head and neck region.

OBJECTIVE

To review literature on cutaneous neoplasms that show a predilection for the head and neck region and that are associated with molecular alterations.

DATA SOURCES

Literature review.

CONCLUSIONS

Common nonmelanoma skin cancers, such as basal and squamous cell carcinomas, show a UV-induced pathogenesis. Basal cell carcinomas are characterized by molecular alterations of the Hedgehog pathway, affecting patched and smoothened genes. While squamous cell carcinomas show UV-induced mutations in several genes, driver mutations are only beginning to be identified. In addition, certain adnexal neoplasms also predominantly affect the head and neck region and show interesting, recently discovered molecular abnormalities, or are associated with hereditary conditions whose molecular genetic pathogenesis is well understood. Furthermore, recent advances have led to an increased understanding of the molecular pathogenesis of melanoma. Certain melanoma subtypes, such as lentigo maligna melanoma and desmoplastic melanoma, which are more often seen on the chronically sun-damaged skin of the head and neck, show differences in their molecular signature when compared to the other more common subtypes, such as superficial spreading melanoma, which are more prone to occur at sites with acute intermittent sun damage. In summary, molecular alterations in cutaneous neoplasms of the head and neck are often related to UV exposure. Their molecular footprint often reflects the histologic tumor type, and familiarity with these changes will be increasingly necessary for diagnostic and therapeutic considerations.

Submerged goiter proven to be metastatic infiltration of a neuro-endocrine Merkel cell carcinoma

Background

Merkel cell carcinoma (MCC) is an uncommon neuroendocrine cutaneous carcinoma. Metastases to the thyroid gland are rare and may present diagnostic difficulties.

Case presentation

A 73-year-old woman presented with a hard mass in the adipose tissue of the right inguinal area. This mass was surgically excised and the histology examination showed the existence of a MCC. CT scans revealed a sizable lesion with imaging features of a submerged goiter, invasive to the upper mediastinum. The patient received chemotherapy following by locoregional radiotherapy at the bed of the excised lesion. During the next 10 months the patient was asymptomatic, serum markers values were normal and CT scans findings were stable. However, afterwards NSE and chromogranin values raised and CT scans revealed an enlargement of the submerged goiter. The patient became symptomatic, mainly experiencing respiratory inconvenience. Surgical excision of the right lobe of the thyroid gland was decided and performed without any complications. The histopathology examination showed infiltration of the thyroid gland by a neuroendocrine carcinoma with characteristics compatible with MCC.

Conclusions

The rare case of metastatic infiltration of the thyroid gland by a MCC based on histological and immunohistochemical findings was described. This case report is of clinical significance indicating that by any abnormal finding in the thyroid gland in patients with a malignant disease, the diagnostic approach should always contain consideration of metastasis from the primary tumor.

Digital Merkel cell carcinoma

Merkel cell carcinoma (MCC) is a rare and biologically aggressive neuroendocrine tumour of the skin. Recent analysis of a surveillance, epidemiology and end results program has shown a statistically significant increase of 8% per year in the age-adjusted rates for MCC of the skin over the past 15 years. MCC commonly presents as a painless, rapidly growing, single red or purple cutaneous nodule. Diagnosis is often delayed until histopathological examination due to the relative rarity of the disease. MCC-specific immunohistochemical markers are available for definitive diagnosis, including anticytokeratin-20-positive stain and thyroid transcription factor-1-negative stains. Because there are no phase III trials to guide management, treatment is often tailored to the individual patient by integrating surgery, radiation and chemotherapy.

First description of Merkel Cell polyomavirus DNA detection in a patient with Stevens-Johnson syndrome

Merkel Cell polyomavirus (MCPyV), a ubiquitous DNA tumor virus, has been found to be associated with Merkel cell carcinoma and chronic lymphocytic leukaemia while other associations are still being explored. MCPyV sequences have also been detected in normal tissues of tumor patients and in the blood of healthy donors. This report documents a new MCPyV association with the Stevens-Johnson syndrome, a rare immune-modulated mucocutaneous process particularly associated with specific drugs and infective agents. A high MCPyV viral load was detected simultaneously in fluid from skin lesions (2.0 × 10(4) copies/ml) and in matched blood (7.4 × 10(5) copies/ml) from a young adult patient after bone marrow transplant for a relapsed T-cell acute lymphatic leukaemia. MCPyV clearance concurred with the complete resolution of skin lesions after 5 days of cidofovir treatment. DNA sequencing classified the amplicons as the European/Italian MKL-1 strain. Given its ubiquitous nature, MCPyV could account for part of Stevens-Johnson syndrome idiopathic cases.

Benefits of combined modality treatment of Merkel cell carcinoma of the head and neck: single institution experience

BACKGROUND

There is ongoing debate surrounding the roles of surgery and adjuvant radiotherapy in the management of primary and recurrent Merkel cell carcinoma of the head and neck. This study assessed the influence of local excision, margin status, adjuvant radiotherapy and chemotherapy on locoregional recurrence and survival.

METHOD

A retrospective review of 54 consecutive cases of head and neck Merkel cell carcinoma at a single institution.

RESULTS

Median disease-specific survival time was 120 months. Forty-four per cent of patients developed locoregional recurrence. Combined treatment with surgery and locoregional radiotherapy improved diseasespecific survival. Radiotherapy was associated with longer time to recurrence and regional recurrence. Irradiation of the regional nodes improved regional control, irrespective of clinical status. Margin-negative excision was not associated with improved local control. Combined modality treatment of recurrent disease resulted in a four-fold improvement of local control, but small numbers prevented this trend from reaching statistical significance.

CONCLUSION

Surgical excision of the primary disease and clinically involved regional nodes, plus adjuvant radiotherapy to the surgical bed and regional nodes are recommended for all patients with Merkel cell carcinoma of the head and neck, irrespective of clinical status. Recurrent disease should be aggressively treated with combined modality treatment.

Orbital metastasis secondary to merkel cell carcinoma: case report and literature review

INTRODUCTION

Merkel cell carcinoma is an aggressive malignancy often associated with metastatic spread, but has never been reported to metastasize to the orbit.

CASE

An 80 year old male with metastatic Merkel cell carcinoma presented with ptosis and extraocular movement abnormalities, and was found to have a lesion of the orbit consistent with metastatic spread. The lesion responded favorably to radiation therapy.

COMMENT

Although the orbit is a frequent site of metastatic disease, this is the first reported case of presumed Merkel cell carcinoma metastasizing to the orbit.

A better prognosis for Merkel cell carcinoma of unknown primary origin

BACKGROUND

There is limited evidence that Merkel cell carcinoma (MCC) arising from a nodal basin without evidence of a primary cutaneous (PC) site has better prognosis. We present our experience at 2 tertiary care referral centers with stage III MCC with and without a PC site.

METHODS

Fifty stage III MCC patients were identified between 1996 and 2011. Clinical data were analyzed, with primary endpoints being disease-free survival and overall survival.

RESULTS

Of stage III patients, 34 patients presented with a PC site and 16 patients with an unknown primary (UP) site. Treatment strategies varied; of patients with UP vs. PC sites, 25% vs. 44% underwent combined regional lymphadenectomy and radiation, with an additional 25% vs. 15% receiving chemotherapy. The median disease-free survival for a UP site was not reached vs. 15 months for a PC site (hazards ratio = .48, P = .18). The median overall survival for a UP site was not reached vs 21 months for a PC site (hazards ratio = .34, P = .03). Multivariate analysis showed that UP status was a significant factor in overall survival (P = .002).

CONCLUSIONS

Stage III MCC with a UP site portends a better prognosis than MCC with a PC site.

Merkel cell carcinoma: what do we know about it and what should we do?

Merkel cell carcinoma (MCC) is a rare primary cutaneous carcinoma of the skin that is highly aggressive, and has a high risk of locoregional and distant spread, a mortality rate considerably higher than that of cutaneous melanoma and poor survival. Its incidence has increased during the past twenty years. The studies published since 2008 have introduced changes in the understanding of its epidemiology and pathogenesis, and consequently the therapeutic approach. Despite this, there is still controversy surrounding its optimal management, which requires clarification. This is the purpose of this review.

Merkel cell carcinoma with lymph node metastasis in the absence of a primary site: Case report and literature review

Merkel cell carcinoma (MCC) is a rare malignant skin neoplasm with the potential for local recurrence, spreading to regional lymph nodes (LNs) and distant metastases. Although it has been identified in various anatomical sites, LN metastatic MCC in the absence of a primary site is extremely rare. The present case reports a 54-year-old male who initially underwent histological examination of a biopsy specimen from the right inguinal LNs. A diagnosis of metastatic small cell carcinoma was made. Nine months later, this diagnosis was changed to MCC with multiple metastases following observation of a tumour mass in the right dorsal thigh. Additionally, in the present study a summary is provided of 23 published cases of MCC with initial LN metastasis in the absence of a primary site, with details of clinical characteristics, natural history and pertinent therapy of this uncommon tumour. The present patient with LN metastatic MCC in the absence of a primary site and the other reported cases demonstrate that although multimodal treatment with surgery, radiotherapy (RT) and chemotherapy provides excellent local control, local recurrence and distant metastases commonly develop in this uncommon tumour. LN metastatic MCC in the absence of a primary site is a highly malignant disease and the role of adjuvant postoperative RT and/or chemotherapy remains to be fully determined.

Radiotherapy for metastatic merkel cell carcinoma: a review of the literature

Introduction. Merkel cell carcinoma is a rare form of non-melanoma skin cancer of neuroendocrine origin. Optimal management of patients is controversial and the role of radiotherapy is unclear. Purpose. The purpose of this study was to review the efficacy of RT in the treatment of both local and distant metastatic disease from MCC. Methods. A literature search was conducted in MEDLINE (1946—January Week 1 2012) and Embase (1980–2012 Week 2). Articles of interest analyze the efficacy of radiotherapy for treatment of metastatic MCC and did not exclude case reports. Results. All articles except one focusing on the role of radiotherapy were of retrospective origin or case series. Significant limitations applied in all studies due to limited sample sizes and the retrospective nature of these studies. Radiotherapy improves locoregional control in the adjuvant setting, and many series suggest an improvement in overall survival. In cases where surgery is not possible, definitive radiotherapy may be an as-efficacious alternative. The radiosensitive nature of MCC coupled with existing reports suggests that treatment via current protocols for other primary tumors is adequate. Conclusion. Further studies should be conducted prospectively to clarify the true role of radiotherapy in metastatic MCC.

Chronic lymphocytic leukemia is associated with decreased survival of patients with malignant melanoma and Merkel cell carcinoma in a SEER population-based study

PURPOSE

To delineate outcomes of malignant melanoma (MM) and Merkel cell carcinoma (MCC) in patients with chronic lymphocytic leukemia (CLL) or non-Hodgkin's lymphoma (NHL).

PATIENTS AND METHODS

We identified patients with MM or MCC reported to the Surveillance, Epidemiology, and End Results program and analyzed the effects of history of CLL/NHL on overall (OS) and cause-specific survival after MM or MCC. Expected survival was derived from patients with MM or MCC without CLL/NHL.

RESULTS

From 1990 to 2006, 212,245 patients with MM and 3,613 patients with MCC were identified, of whom 1,246 with MM and 90 with MCC had a prior diagnosis of CLL/NHL. Patients with MM and a history of CLL/NHL had worse-than-expected OS as measured by standardized mortality ratio (SMR; SMR for CLL, 2.6; 95% CI, 2.3 to 3.0; SMR for NHL, 2.3; 95% CI, 2.1 to 2.6). MM cause-specific survival was worse than expected for patients with a history of CLL (SMR, 2.8; 95% CI, 2.2 to 3.4) or NHL (SMR, 2.1; 95% CI, 1.7 to 2.6). Among patients with MCC, OS was worse than expected for those with a history of CLL (SMR, 3.1; 95% CI, 2.2 to 4.3) or NHL (SMR, 1.9; 95% CI, 1.3 to 2.8). MCC cause-specific survival was worse than expected for patients with a history of CLL (SMR, 3.8; 95% CI, 2.5 to 5.9), but no difference was observed for NHL (SMR, 0.9; 95% CI, 0.4 to 2.1).

CONCLUSION

Patients with CLL before diagnosis of MM or MCC have significantly worse OS and MM or MCC cause-specific survival than those without a history of CLL/NHL.