Merkel cell carcinoma

Best practices in surgical and nonsurgical management of head and neck Merkel cell carcinoma: An update

Merkel cell carcinoma (MCC) is a rare, highly aggressive cutaneous neuroendocrine carcinoma. Controversy exists regarding optimal management of MCC as high-quality randomized studies and clinical trials are limited, and physicians are bound to interpret highly heterogeneous, retrospective literature in their clinical practice. Furthermore, the rising incidence and notably poor prognosis of MCC urges the establishment of best practices for optimal management of the primary tumor and its metastases. Herein, we summarized the relevant evidence and provided an algorithm for decision-making in MCC management based on the latest 2021 National Comprehensive Cancer Network guidelines. Additionally, we report current active MCC clinical trials in the United States. The initial management of MCC is dependent upon the pathology of the primary tumor and presence of metastatic disease. Patients with no clinical evidence of regional lymph node involvement generally require sentinel node biopsy (SLNB) while clinically node-positive patients should undergo fine needle aspiration (FNA) or core biopsy and full imaging workup. If SLNB or FNA/core biopsy are positive, a multidisciplinary team should be assembled to discuss if additional node dissection or adjuvant therapy is necessary. Wide local excision is optimal for primary tumor management and SLNB remains the preferred staging and predictive tool in MCC. The management of MCC has progressively improved in the last decade, particularly due to the establishment of immunotherapy as a new treatment option in advanced MCC. Ongoing trials and prospective studies are needed to further establish the best practices for MCC management.

Merkel Cell Carcinoma, the Impact of Clinical Excision Margins and Mohs Micrographic Surgery on Recurrence and Survival: A Systematic Review

BACKGROUND

When treating Merkel cell carcinoma (MCC), the relation between wide local excision (WLE) margin and recurrence or survival is unclear. Mohs micrographic surgery (MMS) is an alternative surgical option for MCC, but it is unknown whether the local recurrence rate differs between MMS and WLE.

OBJECTIVE

To systematically assess the available literature to determine the recurrence and survival rates when treating MCC with MMS and different clinical excision margins.

MATERIALS AND METHODS

The MEDLINE, EMBASE, and CENTRAL databases were searched. Two independent reviewers selected studies that defined clear excision margins and either recurrence or survival. When possible, individual cases were extracted from case series and included in the analyses. Other studies were reviewed narratively.

RESULTS

Overall, 1108 studies were identified; of which, 19 case series (168 cases) and 12 cohort studies were eligible. None of the cohort studies showed significant differences in recurrence or survival for either excision margins or MMS. Equally, logistic and Cox regression analyses of the case series revealed no significant differences in recurrence or survival between different excision margins and MMS.

CONCLUSION

Synthesis of the available data does not indicate differences in recurrence and/or survival rates for MCC between different clinical excision margins and MMS.

Mohs Micrographic Surgery Versus Wide Local Excision in the Treatment of Merkel Cell Carcinoma: A Systematic Review

BACKGROUND

Merkel cell carcinoma (MCC) is an aggressive neoplasm with high rates of recurrences. Current guidelines recommend wide local excision (WLE) with 1 to 2 cm margins. However, Mohs micrographic surgery (MMS) offers a potential advantage over WLE because of its ability of sparing healthy tissue and assessing 100% of margins.

OBJECTIVE

To systematically evaluate the surgical modalities for the treatment of MCC.

MATERIALS AND METHODS

Eligible articles were identified using MEDLINE, Scopus, EMBASE, and Cochrane Library. All available studies investigating surgical treatment of MCC with WLE or MMS were considered.

RESULTS

Forty studies met the inclusion criteria. Thirty-one studies described patients treated with WLE, 3 with MMS, and 6 with either WLE or MMS. Subgroup analysis of Stage I MCC showed recurrence rates similar in both surgical modalities with local recurrence rate of 6.8% for WLE versus 8.5% for MMS (p = .64) and a regional recurrence rate of 15.2% for WLE versus 15.3% for MMS (p = .99).

CONCLUSION

Overall WLE cases were at a higher stage at presentation. Subgroup analysis showed that MMS is not inferior to WLE excision for the treatment of Stage I MCC and is a reasonable option for anatomic locations where tissue sparing is important.

Recurrence and mortality rates with different treatment approaches of Merkel cell carcinoma: a systematic review and meta-analysis

BACKGROUND

Comprehensive treatment recommendations for Merkel cell carcinoma are complex. We aimed to systematically review the published data on recurrence and mortality rates associated with various treatment approaches for Merkel cell carcinoma.

METHODS

Search of MEDLINE, Embase, Web of Science, and Scopus from inception to August 2015. Studies were included that reported comparative survival and recurrence data for two or more treatment modalities. Two reviewers independently reviewed and abstracted recurrence and mortality rates. Event rates for individual treatment arms in each study were pooled and meta-analyzed across studies using a random-effects model.

RESULTS

Fifty-two retrospective studies met inclusion criteria, revealing a total of 1,804 patients with primary Merkel cell carcinoma with data available for analyses. The recurrence rate was higher for surgery alone (55.0%) versus a combination of surgery and radiotherapy (39.0%) (odds ratio, 2.089; 95% CI, 1.374-3.177; P < 0.001). Combination therapy including surgery, radiotherapy, and chemotherapy had a higher mortality rate (44.6%) than did combined surgery and radiotherapy (23.2%) (odds ratio, 2.688; 95% CI, 1.196-6.037; P = 0.02).

CONCLUSIONS

The treatment of Merkel cell carcinoma with surgery plus adjuvant radiotherapy may produce lower recurrence rates.

Clinical-pathological review of 14 cases of merkel cell carcinoma

Merkel cell carcinoma (MCC) is a rare, primary, cutaneous, neuroendocrine skin tumour that occurs commonly in the head, neck or extremities of elderly white people. Fourteen cases of MCC in the Hamilton Regional Cancer Centre between 1992 and 2000 have been reviewed. Seven cases required a panel of immunohistochemical markers and two cases required electron microscopy for confirmation. Seven men and seven women were treated, and ranged from 67 to 96 years of age (mean 77.7 years). The primary tumour was located in the head and neck in seven patients (50%), in the extremities in four patients (29%) and on the trunk in two patients (14%). One patient had an unknown primary tumour location. Ten patients had stage Ia disease at presentation, three had stage Ib disease, and one presented with stage II disease. Primary treatment consisted of wide local excision in nine patients, wide local excision and radiotherapy in four patients and radiotherapy only in one patient. Seven patients had recurrence, five were disease free up to their most recent follow-up, one died of unrelated causes, and one was lost to follow-up after primary treatment. Of the seven patients with recurrence, two had local recurrence, two had lymph node recurrence and three developed metastases. Disease-free intervals were 69% and 50% for six-month and one-year follow-up, respectively. No difference in outcome was observed between stage Ia and Ib disease. The patient with stage II disease at presentation developed metastases. Longer duration of disease before presentation had a higher incidence of recurrence with distant metastases. Extremity lesions had the best prognosis associated with disease-free interval. Early management with excision and radiotherapy improved the disease-free interval.

Merkel Cell Carcinoma: Therapeutic Update and Emerging Therapies

Merkel cell carcinoma (MCC) is a rare but highly aggressive neuroendocrine skin cancer whose incidence has almost doubled in recent decades. Risk factors for MCC include age > 65 years, immunosuppression, sun exposure and infection by Merkel cell polyomavirus. MCC usually presents as rapidly growing, firm, red to violaceous nodule localized on the sun-exposed skin. Surgery followed by radiation therapy is considered to be the first-line treatment for primary or loco-regional MCC in order to prevent recurrences and lymph node metastasis, while chemotherapy has always been used to treat advanced forms. However, responses to chemotherapy are mostly of short duration, and the associated clinical benefit on overall survival is still unclear. The use of checkpoint inhibitors (CPIs) has shown good results in the treatment of advanced MCC and, consequently, CPIs are considered emerging immunotherapeutic options for these patients, although there are still no standardized treatments for patients with metastatic disease. Here we present a complete overview of the different possibilities for the treatment of MCC according to the stage of the disease, focusing on the emerging immunotherapies used for treating advanced MCC.

Merkel Cell Carcinoma: Updates on Staging and Management

Merkel cell carcinoma is an aggressive neuroendocrine carcinoma with increasing incidence over the past few decades. The TNM Staging System used for Merkel cell carcinoma was updated by the American Joint Committee on Cancer in 2017. Clinical practice guidelines were updated by the National Comprehensive Cancer Network on August 31, 2018. This article reviews the most recent evidence-based updates on staging and management.

Merkel cell carcinoma: An update and review: Current and future therapy

Merkel cell carcinoma (MCC) is a rare neuroendocrine tumor of the skin associated with a high risk of local recurrence and distant metastases. It most commonly occurs on sun-exposed areas of white patients >65 years of age. The Merkel cell polyomavirus (MCV) is thought to be responsible for malignant transformation in approximately 80% of cases in the northern hemisphere, while ultraviolet radiation-induced DNA damage is implicated in MCV-negative tumors. The overall incidence of MCC is low, with approximately 1600 cases diagnosed annually in the United States. The rate is much higher in patients with lymphoproliferative malignancies, solid organ transplants, and HIV infection. The low overall incidence of this tumor makes it challenging to conduct prospective clinical trials with sufficient power. As a result, most management recommendations are based on case series, retrospective reviews, and expert opinion. The pathogenesis, diagnosis, and staging of MCC was discussed in the first article in this continuing medical education series. This article focuses on current management guidelines and promising new therapies in development. Because of the complexity, aggressive nature, and individuality of each case, MCC is best treated by a multidisciplinary team.

Mohs Micrographic Surgery for the Treatment of Merkel Cell Carcinoma

BACKGROUND

Merkel cell carcinoma (MCC) is a rare, aggressive malignant neoplasm. Traditionally, wide local excision has been used for local control. However, the tissue-sparing capability of Mohs micrographic surgery (MMS) and the greater certainty of complete tumor removal offer a potential advantage over wide local excision if MMS offers acceptable cure rates.

OBJECTIVE

This study aims to help elucidate management of MCC and includes one of the largest groups of patients from a single institution.

MATERIALS AND METHODS

This study is a retrospective chart review of 22 patients with cutaneous MCC treated with MMS at our practice over 20 years. Clinical characteristics and outcomes were examined. The study protocol conformed to the ethical guidelines of the 1975 Declaration of Helsinki as reflected in the approval by our institution's human research review committee.

RESULTS

The overall local recurrence rate was 5% (1/22). The overall rate of biopsy-proven metastasis to regional lymph nodes was 14% (3/22). No cases of distant metastases were documented.

CONCLUSION

To our knowledge, this is the largest group of patients with MCC treated with MMS from a single institution and indicates that MMS may be a useful treatment modality for this rare aggressive disease.

Merkel Cell Carcinoma: An Update of Key Imaging Techniques, Prognostic Factors, Treatment, and Follow-up

Merkel cell carcinoma, though rare, is one of the most aggressive tumors a dermatologist faces. More than a third of patients with this diagnosis die from the disease. Numerous researchers have attempted to identify clinical and pathologic predictors to guide prognosis, but their studies have produced inconsistent results. Because the incidence of Merkel cell carcinoma is low and it appears in patients of advanced age, prospective studies have not been done and no clear treatment algorithm has been developed. This review aims to provide an exhaustive, up-to-date account of Merkel cell carcinoma for the dermatologist. We describe prognostic factors and the imaging techniques that are most appropriate for evaluating disease spread. We also discuss current debates on treating Merkel cell carcinoma.

Merkel Cell Carcinoma: Current Issues Regarding Diagnosis, Management, and Emerging Treatment Strategies

Merkel cell carcinoma (MCC) is a rare but aggressive cutaneous tumor with a predilection for the head and neck of elderly Caucasian patients. Although much less common than melanoma, MCC has higher rates of sentinel lymph node involvement, local and regional recurrences, and mortality. The majority of MCC cases have been linked to the relatively newly discovered Merkel cell polyomavirus, which is a ubiquitous constituent of the skin flora. Recent discoveries regarding viral integration and carcinogenesis and the immunologic features of MCC have expanded the understanding of MCC. These discoveries have led to the development and application of emerging therapies such as somatostatin analogs, immune checkpoint inhibition, adoptive cell therapy, and other exciting possibilities for targeted therapy.

Merkel cell carcinoma: Do you know your guidelines?

BACKGROUND

Merkel cell carcinoma (MCC) is a cutaneous neuroendocrine malignancy that exhibits clinically aggressive features and is associated with a poor prognosis. The incidence of MCC seems to be increasing for reasons unknown, and is estimated to be 0.32/100,000 in the United States.

METHODS

This article will review the current literature and National Comprehensive Cancer Network practice guidelines in the treatment of MCC.

RESULTS

Resection of MCC with negative margins remains the mainstay of therapy. Positive nodal disease should be treated with neck dissection and adjuvant radiotherapy. High-risk patients should undergo adjuvant radiotherapy, which improves oncologic outcomes. The role of chemotherapy is less clear and is currently reserved for advanced-stage MCC and palliative therapy.

CONCLUSION

The pathogenesis of MCC has recently been impacted with the discovery of the Merkel cell polyomavirus (MCPyV). Research to establish targeted and immunologic therapeutic options are ongoing.

Spontaneous regression of Merkel cell carcinoma: A case report and review of the literature

INTRODUCTION

Merkel cell carcinoma (MCC) is a rare and highly aggressive primary cutaneous neuroendocrine carcinoma, most often occurring in the elderly. Recurrence is frequent and in 40% of cases regional and distant metastases develop. Despite this, there have been reports of spontaneous regression. We report the first case of MCC with primary complete spontaneous regression of the nose in an 86-year-old woman following an incisional biopsy.

PRESENTATION OF CASE

An 86-year-old woman presented with a violaceous lump on the left side of the nose measuring 25 × 25 mm. Incisional biopsy of the lesion showed MCC and immunohistochemistry confirmed diagnosis. Following an 8-week period the lesion completely disappeared and histology did not show any residual MCC but immunohistochemistry demonstrated a mixture of T and B cells.

DISCUSSION

Complete spontaneous regression (CSR) is rare. The literature documents 22 similar cases of CSR of MCC. From this case report and previous literature the most likely reason for regression is a T-cell mediated immune response.

CONCLUSION

To the best of our knowledge, this is the first described case of MCC with primary CSR of the nose. Exact mechanism of regression remains unclear. Further research is needed in identifying pathway of immune response and possible immunotherapy as a cure.

Merkel cell carcinoma of left groin: a case report and literature review

Merkel cell carcinoma (MCC) is an uncommon highly aggressive skin malignancy with an increased tendency to recur locally, invade regional lymph nodes, and metastasize distally to lung, liver, brain, bone, and skin. The sun-exposed skin of head and neck is the most frequent site of involvement (55%). We report the case of a 63-year-old Caucasian male patient who presented with a recurrent left inguinal mass for the third time after surgical resection with safe margins and no postoperative radio- or chemotherapy. The presented mass was excised, and pathological diagnosis revealed recurrent MCC. The patient underwent postoperative radiation therapy, and 6 months later, he developed a right groin mass which was resected and pathological diagnosis confirmed metastatic MCC. Six months later, patient developed an oropharyngeal mass which was unresectable, and pathological biopsy confirmed metastatic MCC. Patient was offered palliative radio- and chemotherapy. In this paper, we also present a brief literature review on MCC.

Merkel cell carcinoma: the past, the present, and the future

Since the first description of the Merkel cell carcinoma by Cyril Toker in 1972, the number of studies has significantly increased over the last 4 decades. In this review, we will illustrate the historical background of the Merkel cell carcinoma beginning with the 19th century, the first description of the Merkel cell to the finding of the CK20 as a highly specific diagnostic marker and finally to the recently detected Merkel cell polyomavirus (MCPyV). Moreover, we will highlight the beginning of adjuvant therapeutic regimens with radiotherapy and chemotherapy and discuss the diagnostic work-up including imaging and histology of patients with Merkel cell carcinoma. Another very rapidly growing and interesting field of research is the development of patients' specific and tailored targeted therapy, in particular in patients with distant metastatic disease.

The Merkel cell carcinoma challenge: a review from the fine needle aspiration service

Merkel cell carcinoma (MCC) is a highly aggressive neuroendocrine carcinoma of the skin that occurs primarily in elderly or immunocompromised patients. For this report, the authors reviewed the diagnostic challenges associated with MCC encountered on their fine-needle aspiration (FNA) service and also conducted an in-depth review of the literature on MCC. A computer search for patients who were diagnosed with MCC by FNA at the authors' institution from 2006 to 2010 was conducted, and 5 patients were selected for cytologic and immunochemical analyses based on their varied and diagnostically challenging clinical presentations. The 5 selected patients had clinical findings commonly associated with MCC, including advanced age (4 of the 5 patients were ages 75-85 years) and a history of previous malignancies (3 of the 5 patients had a history of previous malignancy), and 1 patient was diagnosed with a concomitant low-grade lymphoma. The patients and their disease illustrated the protean clinical presentation of MCC and the clinical and cytologic challenges associated with this neoplasm. The current findings indicate the need for cytopathologists to be aware of the deceptive presentation of this neoplasm and its cytologic and immunochemical features to correctly diagnose this insidious neoplasm.

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.

AAD/ACMS/ASDSA/ASMS 2012 appropriate use criteria for Mohs micrographic surgery: a report of the American Academy of Dermatology, American College of Mohs Surgery, American Society for Dermatologic Surgery Association, and the American Society for Mohs Surgery

The appropriate use criteria process synthesizes evidence-based medicine, clinical practice experience, and expert judgment. The American Academy of Dermatology in collaboration with the American College of Mohs Surgery, the American Society for Dermatologic Surgery Association, and the American Society for Mohs Surgery has developed appropriate use criteria for 270 scenarios for which Mohs micrographic surgery (MMS) is frequently considered based on tumor and patient characteristics. This document reflects the rating of appropriateness of MMS for each of these clinical scenarios by a ratings panel in a process based on the appropriateness method developed by the RAND Corp (Santa Monica, CA)/University of California-Los Angeles (RAND/UCLA). At the conclusion of the rating process, consensus was reached for all 270 (100%) scenarios by the Ratings Panel, with 200 (74.07%) deemed as appropriate, 24 (8.89%) as uncertain, and 46 (17.04%) as inappropriate. For the 69 basal cell carcinoma scenarios, 53 were deemed appropriate, 6 uncertain, and 10 inappropriate. For the 143 squamous cell carcinoma scenarios, 102 were deemed appropriate, 7 uncertain, and 34 inappropriate. For the 12 lentigo maligna and melanoma in situ scenarios, 10 were deemed appropriate, 2 uncertain, and 0 inappropriate. For the 46 rare cutaneous malignancies scenarios, 35 were deemed appropriate, 9 uncertain, and 2 inappropriate. These appropriate use criteria have the potential to impact health care delivery, reimbursement policy, and physician decision making on patient selection for MMS, and aim to optimize the use of MMS for scenarios in which the expected clinical benefit is anticipated to be the greatest. In addition, recognition of those scenarios rated as uncertain facilitates an understanding of areas that would benefit from further research. Each clinical scenario identified in this document is crafted for the average patient and not the exception. Thus, the ultimate decision regarding the appropriateness of MMS should be determined by the expertise and clinical experience of the physician.

[The role of lymphoscintigraphy in the treatment of Merkel´s cells carcinoma]

The Merkel cell carcinoma is a rare, serious, neuroendocrine, malignant skin cancer with lymph node involvement in half of patients and disseminated metastases in 20% of cases at the time of pathological diagnosis. Its treatment is not fully established, though the sentinel lymph node has been considered essential and may bring benefits to the therapeutic armamentarium of patients.

A review of the epidemiology and treatment of Merkel cell carcinoma

Merkel cell carcinoma is a very rare and aggressive neoplasm. Due to its rarity, therapeutic guidelines are not well established, especially for regionally advanced disease. Articles in English, French, Italian, Portuguese, and Spanish from the last 20 years were identified in MEDLINE and reviewed. The key word "Merkel" was used for the search, relevant articles were selected, and their references were examined. The most important articles related to epidemiology, genesis and treatment were reviewed. The incidence of Merkel cell carcinoma is increasing due to the advancing age of the population, higher rates of sun exposure and an increasing number of immunocompromised individuals. With regard to etiology, the recently described Merkel Cell polyomavirus is thought to play a role. Either local or regional surgical intervention remains the standard of care, but adjuvant radiotherapy or radiotherapy as a primary treatment have been discussed as reasonable therapeutic options. An update on this rare neoplasia is essential because of its increasing incidence and changing treatment options.

Spontaneous regression of Merkel cell carcinoma in a patient with chronic lymphocytic leukemia: a case report

INTRODUCTION

Merkel cell carcinoma is a rare and aggressive primary cutaneous neuroendocrine malignant tumor. The tumor has a high rate of local recurrence after surgical removal. Spontaneous regression appears to be relatively common in this rare type of tumor.

CASE PRESENTATION

We describe the clinical course, cytological and histological findings of a Merkel cell carcinoma in a 70-year-old Caucasian woman, simultaneously diagnosed with chronic lymphatic leukemia. The tumor showed clinical regression after fine needle aspiration. At primary presentation, the tumor had no apparent leukocyte infiltration, but was completely cleared by T-cell mediated immunity within 3 weeks after fine needle aspiration.

CONCLUSION

Fine needle aspiration may have acted as a mechanical trigger involved in the activation of cell-mediated immunity, leading to the clinical and histological regression of the tumor. To the best of our knowledge, this is the first case report of spontaneous regression of Merkel cell carcinoma in a patient with a co-malignancy, that is to say, chronic lymphocytic leukemia.

Metastatic Merkel cell carcinoma in the rectum: report of a case

Merkel cell carcinoma is a rare, aggressive skin malignancy of neuroendocrine origin with predominant occurrence in the elderly males. Approximately 50 percent of patients with Merkel cell carcinoma develop distant metastasis at some point during the disease course; hence, Merkel cell carcinoma always has a poor prognosis. Distant metastasis has never been disclosed in the rectum to the best of our knowledge. We present a 76-year-old male with clinical manifestation of massive hematochezia and final diagnosis of metastatic Merkel cell carcinoma in the rectum. We conclude that radical resection of rectal metastatic Merkel cell carcinoma is important in the management strategy of a patient with recurrence and lymph node metastases.

Merkel cell carcinoma of the head and neck: is adjuvant radiotherapy necessary?

BACKGROUND

Controversy exists regarding the optimal management of patients with Merkel cell carcinoma. The primary aim of this study was to determine whether combined treatment with surgery and radiotherapy improves outcome in a multi-institutional cohort of patients with Merkel cell carcinoma of the head and neck. The secondary aims were to determine by stage, which patients derive benefit from combined therapy and to identify predictors for survival on multivariable analysis.

METHODS

A retrospective analysis of 110 patients with Merkel cell carcinoma of the head and neck was performed. Data were collected from 3 tertiary care institutions (Westmead Hospital, Sydney, Australia; Princess Margaret Hospital, Toronto, Canada; Royal Prince Alfred Hospital, Sydney). There were 78 males and 32 females, median age was 70 years, and mean follow-up of survivors was 2.3 years. Sixty-six patients underwent combined treatment, and 44 patients had either surgery or radiotherapy alone. Analysis by stage was performed using 2 staging systems.

RESULTS

Local and regional control at 5 years was 84% and 69%, respectively. Combined treatment improved both local (p = .009) and regional control (p = .006). Overall and disease-specific survival at 5 years was 49% and 62%, respectively. Combined treatment was associated with significantly better disease-free survival on univariable analysis (p = .013) When analyzed by stage, patients with stage IIb (primary >1 cm, node negative) disease who underwent combined treatment had improved disease-free (p = .005) and disease-specific survival (p = .035). Predictors of survival on multivariable analysis were age >70 years (HR 6.19, p < .001), primary tumor size >1 cm (HR 7.55, p < .001), number of nodal metastases divided into none, <or= 2 and >2 (HR 3.71 per stratum, p < .001). When analyzed with age and disease stage, treatment modality trended toward significance as a predictor of disease-specific (p = .081) and overall survival (p = .076). Disease stage was the most powerful independent predictor on Cox regression (HR 5.43 per stratum, p < .001).

CONCLUSIONS

Merkel cell carcinoma is an aggressive cutaneous malignancy. Age and disease stage are the most important predictors of survival. Combined surgery and radiotherapy improves both locoregional control and disease-free survival. Patients with stage II disease appear to derive the greatest benefit from adjuvant radiotherapy, including improved disease specific survival.

Merkel Cell Carcinoma: Assessing the Effect of Wide Local Excision, Lymph Node Dissection, and Radiotherapy on Recurrence and Survival in Early-Stage Disease—Results From a Review of 82 Consecutive Cases Diagnosed Between 1992 and 2004

BACKGROUND

Wide surgical excision, lymph node dissection, and radiotherapy have been used with varying efficacy in the management of early-stage Merkel cell carcinoma.

METHODS

Records of 82 patients with early-stage Merkel cell carcinoma between 1992 and 2004 were reviewed.

RESULTS

Forty-two patients developed a recurrence, and 44 died during the study period. Twenty-nine patients presented with regional lymph node disease, which was independently associated with diminished survival (hazard ratio [HR], 4.08; 95% confidence interval [CI], 1.55-10.75; P = .005). Lymphadenectomy was independently associated with prolonged disease-free survival (median, 28.5 vs. 11.8 months; HR, .46; 95% CI, .22-.94; P = .034) but not overall survival (P = .25). Margin-negative excision of the primary tumor (60 of 73) was not significantly associated with either prolonged disease-free survival (median, 16 vs. 14 months) or overall survival (median, 54 vs. 34 months). Forty-eight patients received radiotherapy: 36 to the primary site and 31 to the regional lymph nodes. Radiotherapy to both sites was associated with a longer median time to first recurrence (primary site, 24.2 vs. 11.8 months; regional lymph nodes, 46.2 vs. 11.3 months) and survival (primary site, 53.9 vs. 45.7 months; regional lymph nodes, 103.1 vs. 34.2 months). Administration of any radiotherapy was significantly associated with a prolonged time to first recurrence (HR, .39; 95% CI, .20-.75; P = .004) and survival (HR, .39; 95% CI, .18-.82; P = .013) on the Cox regression multivariate analyses.

CONCLUSIONS

Adjuvant radiotherapy to the primary site after surgical excision is recommended in early-stage disease. Involved regional lymph nodes should be treated with radiotherapy with or without lymphadenectomy.

Cisplatin-based chemotherapy for merkel cell carcinoma of the skin

PURPOSE

Merkel cell carcinoma (MCC), a rare tumor of the skin with aggressive behavior, is usually fatal when advanced disease is present. The role of chemotherapy (CT) in the treatment of patients with MCC is unclear.

METHODS

Over 15 years, 9 patients with locally advanced or metastatic disease were treated with carboplatin (CBDCA) (300 mg/m(2) of AUC 5 on Day 1) and etoposide (VP-16) (100 mg/m(2) on Days 1-3) every 3 weeks. As second-line CT, cisplatin (CDDP) (60-100 mg/m(2)), ifosfamide (IFO) (3-5 g/m(2)) and epirubicin (EPI) (30-50 mg/m(2)) were utilized.

RESULTS

Of the 3 patients who received adjuvant therapy, one achieved complete response after 108+ months with second-line chemotherapy and radiotherapy, despite a brief relapse; 2 patients remain disease-free after 84+ and 108+ months. Of the 6 patients with locally advanced or metastatic disease who were treated with first-line chemotherapy, one (16.6 percent) achieved a complete response and 3 (50 percent) achieved partial response, for an overall response rate of 66.6 percent. Two patients (one with complete and one with partial response) received subsequent radiotherapy, following which complete response was achieved. Of the 2 complete responders, one patient remains disease-free after 56+ months. The median overall survival from the time of initial diagnosis for the whole group was 56 months (range 15-114 months); the median overall survival from the initiation of chemotherapy was 18 months (range 6-108+). Local recurrences and soft tissue metastases responded better than visceral metastases. Patients with partial response and no response had rapid disease progression and fatality, despite second-line chemotherapy and/or radiotherapy.

CONCLUSION

MCC appears to be chemosensitive but can progress rapidly with fatal outcomes. Although the rarity of these tumors precludes randomized trials, a common treatment plan should be utilized by those treating MCC. This may allow some conclusions regarding the optimum treatment of patients with MCC to be drawn in the future.

Predictors of survival and recurrence in the surgical treatment of merkel cell carcinoma of the extremities

PURPOSE

Merkel cell carcinoma (MCC) is a rare and aggressive malignancy that originates within the extremities in about 40% of cases. Treatment approaches to this tumor have not been standardized. The purpose of this study was to examine treatment approaches to extremity MCC and to determine predictors of recurrence and patient survival.

METHODS

A retrospective review of 38 consecutive patients with surgically treated extremity MCC was performed. Patient demographics, histologic tumor stage and location and pre-existing malignancies were recorded. Patients were treated by wide-local excision (WLE) or Mohs' technique. Clinically negative regional lymph nodes were either observed (n = 16) or staged with elective lymphadenectomy or sentinel lymph node dissection (SLND) (n = 17), and clinically positive nodes underwent therapeutic node dissection (n = 5). Adjuvant radiotherapy (n = 21) and chemotherapy (n = 6) were noted, as well as time to tumor recurrence and overall patient survival. Predictors of recurrence and survival were analyzed using Kaplan-Meier method and log rank test.

RESULTS

There was no difference in local recurrence rates when comparing Mohs' technique to WLE for the treatment of primary tumors. Although there was no survival advantage to lymph node dissection, lymph node status was effective in predicting the risk of regional recurrence. Radiation reduced the local recurrence rate (HR = 0.29, 95% CI [0.10, 0.85]), but did not lead to improved overall survival.

CONCLUSION

Margin-negative excision of the MCC remains the mainstay of treatment. Surgical staging, preferably with SLND, identifies patients that may develop regional recurrence. This study further supports the important role of adjuvant radiation therapy in improving locoregional tumor control in the patients with MCC.

Immunohistochemical distinction between merkel cell carcinoma and small cell carcinoma of the lung

We assessed the usefulness of several immunohistochemical stains in distinguishing these two neoplasms, including cytokeratin 7, cytokeratin 20 (CK20), neuron-specific enolase, chromogranin, synaptophysin, neurofilaments (NF), thyroid-transcription factor-1 (TTF-1), CD56 antigen, S-100 protein, vimentin, c-erbB-2 oncoprotein, and CD117 antigen. All 13 cases of Merkel cell carcinoma evaluated were positive for CK20, and negative for TTF-1. Twelve of 13 Merkel cell carcinoma cases were positive for NF. Eleven of 13 cases of small cell lung carcinoma were positive for TTF-1. All small cell lung carcinoma cases were negative for NF, and all but one were negative for CK20. In terms of the remaining antigens, there were no differences of significance between the two neoplasms. These findings suggest that a set of three immunohistochemical stains, including CK20, NF, and TTF-1, is useful in affording a distinction between Merkel cell carcinoma and small cell lung carcinoma.

Merkel cell cancer of the skin

Merkel cell carcinoma (MCC) is a rare malignant cutaneous tumor of the elderly with rapidly growing skin nodules found predominantly on sun-exposed areas of the body. The vast majority of patients present with localized disease, while up to 30% have regional lymph node metastases. Despite local excision and the incidence of local recurrence, regional lymph node metastases and distant metastases is high and usually occurs within 2 years of primary diagnosis. The optimal treatment for patients with MCC remains unclear. The best outcome is achieved with multidisciplinary management including surgical excision of primary tumor with adequate margins and post-operative radiotherapy (RT) to control local and regional disease. Patients with regional nodal metastases should be treated with lymph node dissection plus RT. Adjuvant chemotherapy (CT) should be considered as part of the initial management. In case of metastatic disease CT based on regimens used for small-cell lung cancer is the standard treatment of care.

A case report of Merkel cell carcinoma on chronic lymphocytic leukemia: differential diagnosis of coexisting lymphadenopathy and indications for early aggressive treatment

BACKGROUND

Chronic lymphocytic leukemia (CLL) is a monoclonal disorder, characterized by a progressive proliferation of functionally incompetent B lymphocytes. There is increased evidence of association between CLL and skin cancers, including the uncommon Merkel cell carcinoma (MCC).

CASE PRESENTATION

A case report of an 84-year old male, who presented with an aggressively recurrent form of MCC on the lower lip, on the background of an 8-year history of untreated CLL. During the recurrences of MCC, coexisting regional lymphadenopathy, posed a problem in the differential diagnosis and treatment of lymph node involvement. Histopathology and immunoistochemistry showed that submandibular lymphadenopathy coexisting with the second recurrence of MCC, was due to B-cell small lymphocytic lymphoma. The subsequent and more aggressive recurrence of the skin tumor had involved the superficial and deep cervical lymph nodes. Surgical excision followed by involved field radiation therapy has been proven effective for both malignancies.

CONCLUSION

MCC has a high incidence of regional lymphadenopathy at presentation (12-45%) and even when it arises on the background of chronic leukemia, lymphadenopathy at presentation should be managed agressively with elective lymph node dissection. We overview the postulated correlation between Merkel tumor and CCL, the differential diagnosis of regional lymphadenopathy during the recurrences of the skin tumor and the strategies of treatment.

Merkel cell carcinoma: changing incidence trends

BACKGROUND

The objective of this study was to define the incidence trends of Merkel cell carcinoma (MCC), a rare and aggressive cutaneous malignancy.

MATERIALS AND METHODS

All cases of MCC of the skin between 1986 and 2001 were identified using the surveillance, epidemiology, and end results (SEER) program. Overall age-adjusted, gender-specific, age-specific, stage-specific, and regional incidence rates were calculated. All rates are per 100,000 and age-adjusted to the 2000 US standard population. Estimated annual percent change (EAPC) was calculated using a linear least squares model.

RESULTS

A total of 1,124 cases of MCC were identified in the SEER registries. The rate of MCC increased from 0.15 cases per 100,000 in 1986 to 0.44 cases per 100,000 in 2001. The EAPC for the time period was 8.08%. This was statistically significant (95% CI: 6.29, 9.90, P-value < 0.05). Age-specific incidence (5-year age groups) were highest in the elderly, 4.28 per 100,000 in the 85+ age group.

CONCLUSIONS

MCC incidence rates have increased threefold over the 1986-2001 period. Rates are highest in the elderly population. Further etiologic studies and identification of high-risk populations are warranted.

Treatment of Recurrent Merkel Cell Carcinoma: An Analysis of 46 Cases

This report describes the course of recurrent Merkel cell carcinoma and defines possible treatment strategies for recurrent disease as seen in a long-term multisite retrospective analysis. Merkel cell carcinoma is a highly aggressive neuroendocrine skin cancer. Surgery and radiation therapy have been demonstrated ability to control this disease; however, recurrence is common. Systemic chemotherapy has, as yet, no presently defined role in primary treatment, and few conclusions can be reached regarding optimal treatment of disease recurrence. Forty-six patients were identified over the last 15 years in a retrospective analysis of patient records from several hospitals in the San Antonio, TX area. Hospital charts as well as outpatient treatment records were reviewed. Almost all patients developing recurrent disease did so within the first 2 years after primary treatment. Patients presenting distant disease had a median survival of 12 months, faring worse than those who display local or nodal disease. For patients with nodal or local recurrence, the mean survival after combination therapy (chemotherapy, radiation +/- surgery) was 36.5 months as compared with 17.5 months for those treated with a single modality (surgery or radiation or chemotherapy). The overall survival rate for the 46 patients with recurrence was 37%. Multimodality therapy has shown the best results for recurrent Merkel cell carcinoma thus far, and should be used if tolerated by the patient. Aggressive salvage surgery for local or nodal recurrence is encouraged, because this disease has a tendency to become more destructive upon recurrence. Adjuvant radiation therapy should also be used, if the patient has not exceeded their dose limitations. Disseminated disease, whether primary or recurrent, warrants further investigation in terms of optimal treatment.

Merkel cell carcinoma

Merkel cell carcinoma is a rare cutaneous neoplasm most commonly affecting the head and neck of elderly white patients. Even with treatment, Merkel cell carcinoma has a strong propensity toward local recurrence, lymphatic spread, and distant metastasis. Because of its rarity and the subsequent lack of well-controlled clinical trials, no single standard of care exists for the treatment of this aggressive tumor. In our institution, primary lesions are excised with wide margins or by Mohs' micrographic surgery. After local removal, the excision site is treated locally with external radiation therapy. Sentinel lymph node mapping and biopsy are performed. Patients with tumor within a sentinel lymph node undergo lymph node dissection and radiation to the lymphatic basin. Adjuvant chemotherapy is offered to high-risk patients with local disease and to patients with metastases. Patients with distant metastases are treated with a combination of salvage chemotherapy and radiation therapy.

Eyelid Merkel Cell Carcinoma: Report of Three Cases

PURPOSE

To present three cases of Merkel cell carcinoma, a primary cutaneous neuroendocrine tumor that arises from Merkel cells, and to describe their clinical features, diagnosis, and management.

METHODS

Case series.

RESULTS

In only one case, the disease was clinically recognized. In the others, the diagnosis was confirmed by histology, and chalazion was initially suspected in one of them. Surgery was performed in all patients, and there was no evidence of metastatic disease.

CONCLUSIONS

The rarity of eyelid Merkel cell carcinoma and the fact that it can simulate benign entities frequently lead to difficulties in diagnosis and a delay in the establishment of suitable therapy.

Historique, principes, analyse critique de l’efficacité et indications de la chirurgie micrographique de Mohs

OBJECTIVES

To systematically review the literature for studies reporting on the role of Mohs' micrographic (MMS) surgery in the treatment of skin tumors. To show how it is performed in France.

DESIGN

We reviewed with a quality grid all studies indexed in MEDLINE before 2003/01/01 and published in English or French. Data were extracted by two independent reviewers.

MAIN OUTCOME MEASURES

Quality of clinical studies, recurrence rates, number of patients lost to follow-up.

RESULTS

No randomized study was found among the 493 references found. Studies of lower quality, on procedures similar to MMS, or previous systematic reviews were therefore selected. In tumors such as basal (BCC) or spinous (SCC) cell carcinoma, microcystic adnexal carcinoma, dermatofibrosarcoma protuberans, and Merkel cell carcinoma, MMS commonly induced lower recurrence rates than figures reported for conventional treatments and/or reduced surgical margins. Studies on melanoma were of low quality.

CONCLUSIONS

Although no evidence-based guidelines could be developed, MMS should be used mainly for larger, morphea, micronodular or infiltrative-type, or recurrent BCCs located in danger zones, but also (sometimes with a slightly modified procedure) in microcystic adnexal carcinomas, dermatofibrosarcoma protuberans, Merkel cell carcinoma, and in aggressive forms of SCC. Randomized, controlled studies should be performed.

Eccrine porocarcinoma arising in a seborrheic keratosis evaluated with dermoscopy and treated with Mohs' technique

A 78-year-old white woman returned for a routine 6-month skin cancer examination. She had a history of actinic keratosis and multiple basal cell carcinomas. She had no personal or family history of dysplastic nevi or melanoma. The patient was asymptomatic and unaware of any new or changing skin lesions. The patient had multiple lentigines, hemangiomas, and actinic and seborrheic keratoses on all sun-exposed areas. There were no less than 10 seborrheic keratoses on the right mid-back, and one was found to have a 1-cm, reddish nodule asymmetrically located within it (Figs 1 and 2). A clear papule on the left preauricular area was found on biopsy to be a basal cell carcinoma. The nodule on the back was still present 1 month later and it was felt that further evaluation was indicated. As melanoma has been reported to develop in seborrheic keratoses, we decided to examine the lesion using digital dermoscopy. With digital dermoscopy, a well-demarcated reddish nodule was asymmetrically located within a brown lesion. It blanched significantly with pressure. Within the nodule, there were dotted and irregular linear vessels (atypical vascular pattern; also known as polymorphous vascular pattern) and regular-appearing brown dots. Surrounding the reddish nodule, there were pale and pigmented, comedo-like openings, fissures, and ridges (brain-like appearance). Some of the follicular openings appeared to be within the wall of the nodule (Figs 3 and 4). Comedo-like openings, fissures, and ridges are primary dermoscopic criteria for the diagnosis of a seborrheic keratosis; however, the vascular pattern seen has not been reported in seborrheic keratosis. Due to the patient's age and the rarity of significant pathology arising in a seborrheic keratosis, a shave biopsy was performed. To our surprise, the specimen was interpreted by an experienced dermatopathologist as a well-differentiated eccrine porocarcinoma. Due to the high local recurrence rate and metastatic potential of this carcinoma, the patient was referred for Mohs' surgery. Both the basal cell carcinoma and the eccrine porocarcinoma were excised in one stage. A metastatic work-up was negative and the patient appears to be doing well.

Merkel cell carcinoma: a clinical, histopathologic, and immunohistochemical review

Merkel cell carcinoma is a rare aggressive neoplasm, with about 400 cases diagnosed in the United States each year. Among the cutaneous-derived neoplasms, it is the most deadliest, with a higher mortality rate than melanoma. Although the classic clinical presentation as a rapidly growing papule in a sun-exposed site of an elderly patient is not specific, certain histopathologic and ancillary pathologic features allow for its discrimination in most cases. Herein, we review the etiology, pathogenesis, clinical, and pathologic attributes as well as the staging treatment and prognosis of this important public health menace.

Skin cancer in organ transplant recipients: Epidemiology, pathogenesis, and management

In the United States more than 100,000 people are living with solid organ transplants. The intense immunosuppressive regimens necessary for prolonged survival of allografts significantly increase the rates of both internal and cutaneous malignancies in recipients of solid organ transplants. Skin cancer is the most common cancer in patients after transplantation. Because of the early onset and high tumor burden in transplant recipients, dermatologists have significant challenges in managing the treatment of these patients. This article describes the epidemiology and clinical presentation of skin cancer during posttransplantation immunosuppression, discusses pathogenic cofactors, and reviews the optimal management for mild and severe skin cancer in transplant recipients.

The effect of aloe emodin on the proliferation of a new merkel carcinoma cell line

A free-floating cell line has been established from a metastatic lesion of a Merkel cell carcinoma (MCC) patient. The cell line was characterized by immunocytochemical reactions with antibodies against the epithelial and neuroendocrine antigens: cytokeratin 20, neuron-specific enolase, chromogranin A, neurofilament protein, synaptophysin, and calcitonin. Karyotype analysis of the MCC cells showed deletion in chromosomes 3 and 7, loss of chromosome 10, and several translocations in other chromosomes. No mutation was detected in the TP53 gene, after analyzing the complete coding region. Growth factors such as basic fibroblast growth factor, transforming growth factor-beta, and nerve and epidermal growth factors had no effect on the proliferation of the cells. The differentiation-inducing agents sodium butyrate and dimethyl sulfoxide, especially the former, markedly inhibited the proliferation of the MCC cells. Aloe emodin, a natural constituent of aloe vera leaves, significantly inhibited the growth of MCC cells. Aloe emodin has been reported to be nontoxic for normal cells but to possess specific toxicity for neuroectodermal tumor cells. Differentiation-inducing agents, and aloe emodin, merit further investigation as potential agents for treating MCC.