Clinical management and treatment outcomes of Merkel cell carcinoma

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.

Oncologic outcomes of patients with Merkel Cell Carcinoma (MCC): A multi-institutional cohort study

BACKGROUND

Merkel cell carcinoma (MCC) is a rare cutaneous neuroendocrine tumor that primarily affects elderly patients. Despite aggressive treatment, overall survival (OS) remains low.

METHODS

This study is a multi-institutional, retrospective review of 102 patients with MCC. We evaluated OS, disease-specific survival (DSS), and risk factors for recurrence.

RESULTS

Median age of patients was 71.46% of patients recurred. Patients with stage I disease had median 5-year OS of 59.3%, compared to 68.1% DSS. For stage III, median 5-year OS was 46.0% vs 58.2% DSS. Disease stage and advanced age were risk factors for recurrence and decreased OS. Immunocompromised status and disease stage were the strongest predictors of DSS.

CONCLUSIONS

DSS is significantly better than OS for patients with MCC. Many elderly patients with newly diagnosed MCC have low remaining life expectancy, regardless of their MCC diagnosis. Patient age and overall health status should be considered to personalize care plans for patients with MCC.

The important role of radiation treatment in the management of Merkel cell carcinoma

Merkel cell carcinoma is an aggressive, radiosensitive cutaneous neuroendocrine tumour. In this review, the roles of radiation therapy and chemoradiation in the management of Merkel cell carcinoma are described and discussed, and guidelines for patient management are presented. Radiation treatment may be indicated for definitive (> 55 Gy) or adjuvant (> 50 Gy) treatment of the primary tumour site and for prophylactic (> 50 Gy), adjuvant (> 50 Gy) or definitive (> 55 Gy) treatment of the regional lymph node field. If a patient presents with positive margins after initial biopsy or resection, definitive radiation therapy or chemoradiation may be an alternative to further surgery and, importantly, results in less delay than re-resection followed by adjuvant radiation treatment. Given the rarity of this tumour, patients should be enrolled on prospective databases and clinical trials, and managed in a multidisciplinary clinical setting wherever possible.

The role of postoperative radiation and chemoradiation in merkel cell carcinoma: a systematic review of the literature

OBJECTIVE

A systematic review of the literature was undertaken to investigate whether adjuvant radiotherapy and/or chemotherapeutics offered any additional benefit than surgery alone in the treatment of Merkel Cell Carcinoma (MCC).

METHODS

A PubMed, MEDLINE search was conducted between 1995 and 2013, to identify reported cases of surgically treated MCC followed by either observation, radiation, or chemoradiation. Patient demographics and outcomes were recorded and compared in a systematic fashion.

RESULTS

Thirty-four studies (n = 4475) were included. The median age was 73 years, median follow up was 36 months and there was a 1.5:1 ratio of men to women. All 4475 patients had surgery, 1975 had no further treatment, 1689 received postoperative RT, and 301 received postoperative chemoRT. The most common site was face/head/neck, 47.8%. Stage 1 was the most common clinical stage at diagnosis (57%). Three-year local control was 20% (median 10%) in the observation cohort, compared to 65% (62%) with postoperative RT, and 67% (75%) with postoperative chemoRT; these findings were statistically significant (P < 0.001). Recurrence was found to be 38% (60%) in the observation cohort, compared to 23% (20%) with postoperative RT (P < 0.001). Three-year overall survival (OS) was found to be 56% (57%) in the observation cohort, compared to 70% (78%) with postoperative RT and 73% (76%) with postoperative chemoRT (P < 0.001). The observation cohort had a median OS of 44 months compared with 64 months (P < 0.001) in the postoperative RT cohort. There was no statistically significant difference in any parameters assessed between postoperative radiation and postoperative chemoradiation arms.

CONCLUSION

The comprehensive collection of retrospective data suggests a survival and control benefit for postoperative radiation in MCC. No differences were noted between adjuvant radiation and chemoradiation. This analysis indicates the need for prospective trials with patients stratified by known prognostic factors.

Merkel cell carcinoma of the head and neck: a single institutional experience

Merkel cell carcinoma (MCC) is a rare cutaneous malignancy occurring mostly in older immunocompromized Caucasian males. A growing incidence of MCC has been reported in epidemiological studies. Treatment of MCC usually consists of surgical excision, pathological lymph node evaluation, and adjuvant radiotherapy. This paper reports the experience of a single tertiary center institution with 17 head and neck Merkel cell carcinoma patients. Median followup for the cohort was 37.5 months. After five years, recurrence-free survival, disease specific survival, and overall survival were 85%, 90%, and 83%, respectively. Our limited data support the use of adjuvant radiotherapy. We also report two cases of MCC located at the vestibule of the nose and two cases of spontaneous regression after diagnostic biopsy. About 40% of our patients were referred to our center for surgical revision and pathological lymph node evaluation. Increased awareness of MCC and an interdisciplinary approach are essential in the management of MCC.

Multidisciplinary management in Merkel cell carcinoma

Herein, the authors describe the experience with the treatment of Merkel cell carcinoma (MCC) and review the literature regarding MCC treatment regimens. Nine patients underwent treatment due to stage I, II, or III MCC. The median follow up was 39 months. In five cases, tumors were excised with skin margins of >2 cm, and skin margins were <2 cm in four patients. Local adjuvant radiotherapy (RT) was given to four patients, while three patients underwent local lymphadenectomy (LAD). Local recurrence occurred in four patients who did not undergo RT (among them three patients had excision margins <2 cm) after a mean time of 9 months. Despite retreatment, two of those patients developed metastases. Recurrence-free survival after primary therapy was achieved: (a) in three patients with stage I and II MCC treated surgically with excision margins <2 cm combined with RT or wide excision >2 cm alone and (b) in two patients with stage III MCC treated with wide excision and LAD combined with local and regional RT. A review of the literature supports the following recommendations: (a) excision with adequate margins combined with RT; (b) LAD with regional RT in cases of lymph node involvement; and (c) sentinel lymph node biopsy in patients without clinically suspicious lymph nodes.

Radiotherapy is associated with significant improvement in local and regional control in Merkel cell carcinoma

Introduction

Merkel cell carcinoma (MCC) is a rare tumour of skin. This study is a retrospective audit of patients with MCC from St Vincent’s and Mater Hospital, Sydney, Australia. The aim of this study was to investigate the influence of radiotherapy (RT) on the local and regional control of MCC lesions and survival of patients with MCC.

Method

The data bases in anatomical pathology, RT and surgery. We searched for patients having a diagnosis of MCC between 1996 and 2007. Patient, tumour and treatment characteristics were collected and analysed. Univariate survival analysis of categorical variables was conducted with the Kaplan-Meier method together with the Log-Rank test for statistical significance. Continuous variables were assessed using the Cox regression method. Multivariate analysis was performed for significant univariate results.

Results

Sixty seven patients were found. Sixty two who were stage I-III and were treated with radical intent were analysed. 68% were male. The median age was 74 years. Forty-two cases (68%) were stage I or II, and 20 cases (32%) were stage III. For the subset of 42 stage I and II patients, those that had RT to their primary site had a 2-year local recurrence free survival of 89% compared with 36% for patients not receiving RT (p<0.001). The cumulative 2-year regional recurrence free survival for patients having adjuvant regional RT was 84% compared with 43% for patients not receiving this treatment (p<0.001). Immune status at initial surgery was a significant predictor for OS and MCCSS. In a multivariate analysis combining macroscopic size (mm) and immune status at initial surgery, only immune status remained a significant predictor of overall survival (HR=2.096, 95% CI: 1.002-4.385, p=0.049).

Conclusions

RT is associated with significant improvement in local and regional control in Merkel cell carcinoma. Immunosuppression is an important factor in overall survival.

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.

Merkel cell tumor of the skin treated with localized radiotherapy: are widely negative margins required?

Merkel's cell carcinoma is a rare cutaneous tumor that can affect a wide variety of sites throughout the body. Commonly, it affects the skin alone and the management of limited disease can be confusing since the natural history of the disease involves distant metastasis. Traditional management has required wide local excision with negative margins of resection. We describe a case treated with local therapy alone and review the literature to suggest that complete microscopic excision may not be required if adjuvant radiotherapy is used.

Effect of radiotherapy dose and volume on relapse in Merkel cell cancer of the skin

PURPOSE

To assess the effect of radiotherapy (RT) dose and volume on relapse patterns in patients with Stage I-III Merkel cell carcinoma (MCC).

PATIENTS AND METHODS

This was a retrospective analysis of 112 patients diagnosed with MCC between January 2000 and December 2005 and treated with curative-intent RT.

RESULTS

Of the 112 evaluable patients, 88% had RT to the site of primary disease for gross (11%) or subclinical (78%) disease. Eighty-nine percent of patients had RT to the regional lymph nodes; in most cases (71%) this was for subclinical disease in the adjuvant or elective setting, whereas 21 patients (19%) were treated with RT to gross nodal disease. With a median follow-up of 3.7 years, the 2-year and 5-year overall survival rates were 72% and 53%, respectively, and the 2-year locoregional control rate was 75%. The in-field relapse rate was 3% for primary disease, and relapse was significantly lower for patients receiving >or=50 Gy (hazard ratio [HR] = 0.22; 95% confidence interval [CI], 0.06-0.86). Surgical margins did not affect the local relapse rate. The in-field relapse rate was 11% for RT to the nodes, with dose being significant for nodal gross disease (HR = 0.24; 95% CI, 0.07-0.87). Patients who did not receive elective nodal RT had a much higher rate of nodal relapse compared with those who did (HR = 6.03; 95% CI, 1.34-27.10).

CONCLUSION

This study indicates a dose-response for subclinical and gross MCC. Doses of >or=50 Gy for subclinical disease and >or=55 Gy for gross disease should be considered. The draining nodal basin should be treated in all patients.

[Merkel cell carcinoma: study of 24 cases and review of the literature]

Merkel cell carcinoma is a cutaneous-neuroendocrine tumor, which may be difficult to diagnose and to treat.

OBJECTIVE

The objective of this study was to analyse the treatment and the recurrences of Merkel cell carcinoma.

PATIENTS AND METHODS

A retrospective study was performed on the patients operated of a Merkel cell carcinoma between 1994 and 2004. Clinical data of the patients and the tumor, treatment (surgery and radiotherapy) and recurrences were entered in a database.

RESULTS

Twenty-four patients were operated (8 men and 16 women). The mean age at diagnosis was 71.5 years. The average follow-up was 30.8 months. The treatment was a large surgical removal of the tumor with immediate closure, systematically followed by radiotherapy. There were five recurrences and no death.

CONCLUSION

Merkel cell carcinoma is an aggressive tumor. Immediate closure after large surgical removal allows radiotherapy.

Merkel cell carcinoma of the face: an analysis of 16 cases in the Japanese

BACKGROUND

There is no agreement regarding a staging system and optimal treatment of Merkel cell carcinoma. Some centres have reported results from larger series of patients, but these do not include Asian or Japanese centres.

OBJECTIVE

The purpose of this study was to retrospectively review our experience with the surgical treatment of MCC of the face in the Japanese and to study its management and outcome using the staging system described by Clark et al.

METHODS

We report our experiences with 16 cases between 1991 and 2004. Patients and tumour characteristics, treatment variables and outcome were analysed.

RESULTS

The follow-up periods ranged from 1 to 180 months. The average was 32.6 months and the median was 17.5 months. The relapse-free survival for all patients was 51% at 2 years. The relapse-free survival was 80% for the patients with Stage I and 33% with Stage II at 2 years.

CONCLUSION

This staging system was suggested to reflect prognosis although the number of patients in this series was small. Sentinel lymph node biopsy should be considered to determine the accurate nodal staging, and patients with MCC of the head and neck may be treated according to the revised staging system by Clark et al.

Management of merkel cell carcinoma: the roles of lymphoscintigraphy, sentinel lymph node biopsy and adjuvant radiotherapy

BACKGROUND

Merkel cell carcinoma (MCC) is an uncommon, highly aggressive skin malignancy with a propensity to recur locally and regionally. However, its optimal treatment is uncertain. In this study, we aimed to assess the roles of lymphoscintigraphy and sentinel node (SN) biopsy, as well as radiotherapy, in the treatment of MCC.

PATIENTS AND METHODS

A retrospective analysis of 17 patients diagnosed with MCC (median age 74 years) over a 7-year period (median follow-up 16 months) was performed.

RESULTS

Of 11 patients. 3 had a positive SN biopsy and, despite adjuvant radiotherapy, 2 of these 3 developed regional lymph node (RLN) recurrence. Of the remaining 8 patients who had a negative SN biopsy, however, 5 also had RLN recurrences. There were 9 patients who received adjuvant radiotherapy (RT) to the primary site, with no in-field recurrences; and 8 who received RT to their RLN field, with only 2 developing regional nodal recurrences-both were SN biopsy positive. During the follow-up period, 2 patients died, only 1 due to MCC.

CONCLUSION

The results suggest that SN status may not be an accurate predictor of loco-regional recurrence in MCC. However, they strongly reinforce previous reports that radiotherapy, both locally and to regional nodes, provides effective infield disease control.

A comparison of merkel cell carcinoma and melanoma: results from the california cancer registry

INTRODUCTION

Melanoma and Merkel cell carcinoma (MCC) are both aggressive skin malignancies associated with immunosuppression and possible UV exposure. Both tumors get similar surgical treatment; however, MCC is a relatively rare tumor in which less is known about prognosis and clinical behavior.

METHODS

The California Cancer Registry (CCR), a population-based registry, was reviewed from the years 1988-2003. Merkel cell carcinoma and melanoma were compared with relation to gender, age, ethnicity, disease stage, site, and survival.

RESULTS

A total of 113,187 cases of melanoma and 1,878 cases of MCC were identified in the CCR. Though both cancers are more common in men than in women, MCC had a higher incidence in men than melanoma (63% vs 57% p < 0.005). MCC occurs in the more elderly, with 73.6% of cases occurring in people over 70 years. In contrast, 69% of melanoma cases occurred in people younger than 70 years (p < 0.005). MCC shows a predilection for the head and neck compared to melanoma (47% vs 25.8%) Additionally, melanoma occurs more frequently on the trunk than MCC (30% vs 8.7%). Finally, the 10-year cumulative survival is lower for MCC than for melanoma (17.7% vs 61.3%, p < 0.005).

CONCLUSION

Many clinicians assume MCC and melanoma behave similarly. However, MCC occurs in an older population, more frequently on the head and neck, in a higher percentage of men. Additionally, MCC has a higher rate of regional metastasis and thus may have more of a benefit from regional staging procedures. Overall, MCC has a worse prognosis.

A comprehensive review of the treatment of Merkel cell carcinoma

Merkel cell carcinoma (MCC) is an uncommon but malignant cutaneous neuroendocrine carcinoma with a high incidence of local recurrence, regional lymph node metastases, and subsequent distant metastases. The etiology of MCC remains unknown. It usually occurs in sun-exposed areas in elderly people, many of whom have a history of other synchronous or metachronous sun-associated skin lesions. The outcome for most patients with MCC is generally poor. Surgery is the mainstay of treatment. The role of adjuvant therapy has been debated. However, data from recent development support a multimodality approach, including surgical excision of primary tumor with adequate margins and sentinel lymph node dissection followed by postoperative radiotherapy in most cases, as current choice of practice with better locoregional control and disease-free survival. Patients with regional nodal involvement or advanced disease should undergo nodal dissection followed by adjuvant radiotherapy and, perhaps, systemic platinum-based chemotherapy in most cases.

Merkel cell carcinoma: critical review with guidelines for multidisciplinary management

Merkel cell carcinoma (MCC) is a relatively rare cutaneous malignancy that occurs predominantly in the older white population. The incidence of MCC appears to have tripled during the past 20 years; an increase that is likely to continue because of the growing number of older Americans. The pathogenesis of MCC remains largely unknown. However, ultraviolet radiation and immunosuppression are likely to play a significant pathogenetic role. Many questions currently remain unanswered regarding the biologic behavior and optimal treatment of MCC. Large, prospective, randomized studies are not available and are unlikely to be performed because of the rarity of the disease. The objective of this review was to provide a comprehensive reference for MCC based on a critical evaluation of the current data. The authors investigated the importance of sentinel lymph node biopsy as a staging tool for MCC to assess the status of the regional lymph node basin and to determine the need for additional therapy to the lymph node basin. In an attempt to standardize prospective data collection with the intention to define prognostic indicators, the authors also present histopathologic profiles for primary MCC and sentinel lymph nodes. The controversies regarding the appropriate surgical approach to primary MCC, the use of adjuvant radiation therapy, and the effectiveness of adjuvant chemotherapy were examined critically. Finally, the authors have provided treatment guidelines based on the available evidence and their multidisciplinary experience.

Merkel Cell Carcinomas

Merkel cell carcinoma (MCC) is a rare and extremely aggressive skin cancer that arises from primary neural cells. It presents most commonly in the elderly and immunocompromised patients. Pathologically, MCC should be distinguished from extrapulmonary small cell lung cancer or metastatic small cell lung cancer or a small cell variant of melanoma. The prognosis is based largely on the stage of disease at the time of presentation. Therapeutic options for MCC include wide resection with or without adjuvant radiotherapy or chemotherapy. Novel therapies based on the understanding of the molecular aspects of MCC are currently being explored.

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.

Merkel cell carcinoma

Merkel cell carcinoma (MCC) is a rare, aggressive cutaneous cancer that predominately affects elderly Caucasians with fair skin and has a propensity for local recurrence and regional lymph node metastases. A variety of terms have been used to describe this tumor, including trabecular cell carcinoma, neuroendocrine or primary small cell carcinoma of the skin, and anaplastic cancer of the skin. Although the skin lesion is most commonly found on sun-exposed areas of the head and neck or extremities, it can occur on the trunk, genitalia, and perianal region. The median age is 69 years, but it may occur earlier and more frequently in immunosuppressed patients. Patients with MCC frequently present with a nonspecific erythematous or violaceous firm nodule or small plaque that may be surrounded by small satellite tumors. MCC usually arises in the dermis and extends into the subcutis. It may be difficult to accurately diagnose MCC by light microscopy alone and ancillary techniques, including electron microscopy and immunohistochemistry, may be necessary to make a definitive diagnosis. Management of MCC is dependent on stage of the disease and is hampered by its rarity and lack of randomized trials. Nonetheless, for localized disease most guidelines include wide local excision of the primary tumor either alone or with radiation therapy. Sentinel lymph node biopsy can be helpful in staging and prognosis, but its benefit in survival remains to be seen. Systemic chemotherapy, akin to regimens for small cell carcinoma of the lung, may be considered as an adjuvant following surgery or to treat locoregional or distant disease. The prognosis of MCC is variable. Some patients with localized disease have an indolent course and are well controlled with local excision alone. On the other hand, many tumors are aggressive and have a tendency for locoregional recurrence and distant metastases. Such patients have a grim prognosis with a median survival of 9 months. Successful outcomes are most often seen in patients with early diagnosis and complete excision.

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.

Merkel cell carcinoma (primary cutaneous neuroendocrine carcinoma): An overview on management

Merkel cell carcinoma is an uncommon but aggressive primary cutaneous neuroendocrine (small cell) carcinoma. There is ongoing debate regarding the optimal treatment of this disease. The early literature comprised small institutional studies with inherent weaknesses. Recent data have emerged from larger studies, including those from Australian institutions, that adds support to a multimodality approach as best practice. Despite this, the outcome for patients with unfavourable disease remains poor and in most series 25-30% of patients die as a direct result of Merkel cell carcinoma. The head and neck is the commonest site for presentation (50-60%) and wide excision (2-3 cm) of the primary lesion is usually recommended, although achieving this is often difficult within functional and cosmetic constraints. All clinically node-negative patients should be considered candidates for elective nodal treatment and those with clinical nodal disease should undergo nodal dissection and adjuvant radiotherapy. Recent evidence suggests that patients treated with surgery and adjuvant locoregional radiotherapy experience a better disease-free survival compared with those undergoing surgery alone. The role of platinum-based chemotherapy is evolving. The aim of this article is to discuss relevant issues in the management of a patient with Merkel cell carcinoma.

Merkel cell carcinoma: improved outcome with adjuvant radiotherapy

BACKGROUND

Merkel cell carcinoma is an aggressive primary cutaneous neuroendocrine carcinoma. Patients remain at high risk of locoregional and distant relapse despite treatment. Most studies support the incorporation of locoregional adjuvant radiotherapy in reducing the risk of relapse.

METHODS

Between 1980 and 2002, 86 patients diagnosed with Merkel cell carcinoma were treated with curative intent at Westmead Hospital, Sydney. Multivariate analysis was performed using Cox regression analysis. Disease-free survival and overall survival was calculated using Kaplan-Meier survival curves.

RESULTS

Median age at diagnosis was 75 years (range 46-89 years) in 49 men and 37 women. Median duration of follow up was 31 months (range 6-153 months). Fifty-one (59%) patients presented with a primary lesion, 19 (22%) with a primary lesion and clinical nodal disease and 16 (19%) with lymph node metastases from an unknown primary. A total of 47 of 86 (55%) relapsed with regional nodal relapse, the commonest site of first relapse. Local relapse was similar for patients undergoing surgery (5/37; 14%) compared with surgery and adjuvant radiotherapy (3/25; 12%). Nodal relapse occurred in 14 of 36 (37%) treated with surgery compared with 7 of 38 (18%) patients treated with surgery and adjuvant radiotherapy. Patients treated with surgery and adjuvant radiotherapy experienced a better median disease free survival compared to those undergoing surgery alone (10.5 months vs 4 months; P < 0.01). The 5-year overall and disease-free survival rate for the entire study population was 47% and 25%, respectively. Twenty-six patients (30%) died as a result of Merkel cell carcinoma.

CONCLUSION

Merkel cell carcinoma is an aggressive skin cancer. The addition of adjuvant radiotherapy markedly improves regional control rates and should be considered best practice.

Adjuvant locoregional radiotherapy as best practice in patients with Merkel cell carcinoma of the head and neck

BACKGROUND

Australians have the highest rate of skin cancer in the world. Merkel cell carcinoma (MCC) is the most aggressive skin cancer reported, with a high propensity for relapse. The purpose of this study was to report the patterns of recurrence after initial treatment, the outcomes, and any predictors for survival.

METHODS

We identified 37 patients who were diagnosed with MCC of the head and neck between 1980 and 2002. In this retrospective analysis, multivariate analysis was performed by use of Cox regression analysis. Disease-free survival (DFS) and overall survival (OS) were calculated with Kaplan-Meier survival curves.

RESULTS

The median age at diagnosis was 75 years (range, 46-89 years), with 24 men and 13 women. The median duration of follow-up was 26 months (range, 7-104 months). Twenty-nine patients (78%) initially were seen with a primary lesion, and eight (22%) had a primary lesion and clinical nodal disease. A total of 24 (65%) of 37 patients had a relapse, with regional relapse the most common site of the first relapse (12 of 37). The rates of local relapse were similar for patients undergoing local surgery (three of 17; 18%) or surgery and adjuvant radiotherapy (two of 19; 11%). Nodal relapse developed in seven (50%) of 14 patients not receiving regional treatment compared with six (26%) of 23 patients receiving regional treatment of some type. Patients treated with surgery and adjuvant radiotherapy experienced a significantly longer median DFS than did those undergoing surgery alone (23 months vs 6 months; p < .01). The 3-year OS and DFS rates for the entire study population were 66% and 25%, respectively.

CONCLUSION

MCC is an aggressive skin cancer. There is a sufficient body of evidence, including this study, to consider the addition of adjuvant locoregional radiotherapy as best practice in markedly improving freedom from relapse.

Merkel cell carcinoma of the head and neck

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

Epidemiology of primary Merkel cell carcinoma in the United States

BACKGROUND

Merkel cell carcinoma (MCC) is a rare, aggressive skin cancer.

OBJECTIVE

We sought to describe primary MCC incidence trends, epidemiology, and predictors of survival.

METHODS

The population covered by the Surveillance, Epidemiology, and End Results Program was analyzed as a prospective cohort. We measured age-adjusted incidence rates (per 100,000 person-years) and effect of age, anatomic site, and stage on survival.

RESULTS

Incidence was higher in males (0.34) than in females (0.17). Cases (n = 1034) occurred mostly in whites (94%), in people older than 65 years (76%), and at the head (48%). The 5-year relative survival was 75%, 59%, and 25% for localized, regional, and distant MCC, respectively. Female sex, limb presentation, localized disease, and younger age were positive predictors of survival.

CONCLUSION

The highest incidence of MCC was observed in whites, males, and in people older than 65 years. Only 49% of cases were reported as localized. Better survival was associated with limb localization, early-stage disease, younger age, and female sex.

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.

High-risk Merkel cell carcinoma of the skin treated with synchronous carboplatin/etoposide and radiation: a Trans-Tasman Radiation Oncology Group Study--TROG 96:07

PURPOSE

The effectiveness of synchronous carboplatin, etoposide, and radiation therapy was prospectively assessed in a group of patients with high-risk Merkel cell carcinoma (MCC) of the skin.

PATIENTS AND METHODS

Patients were eligible if they had disease localized to the primary site and nodes, and were required to have at least one of the following high risk features: recurrence after initial therapy, involved nodes, primary tumor size greater than 1 cm, gross residual disease after surgery, or occult primary with nodes. Radiation was delivered to the primary site and nodes to a dose of 50 Gy in 25 fractions over 5 weeks and synchronous carboplatin (area under the curve, 4.5) and intravenous etoposide 80 mg/m2 days 1 to 3 was given in weeks 1, 4, 7, and 10. The median age of the group was 67 (range, 43-86) years, and there were 39 males and 14 females. Involved nodes (stage II) were present in 33 cases (62%). The sites involved were head and neck (22 patients), occult primary (13 patients), upper limb (eight patients), lower limb (eight patients), and trunk (two patients).

RESULTS

Fifty-three patients were entered between 1996 and 2001. The median potential follow-up was 48 months. There were no treatment related deaths. The 3-year overall survival, locoregional control, and distant control were 76%, 75%, and 76%, respectively. Tumor site and the presence of nodes were factors that were predictive for local control and survival. Multivariate analysis indicated that the major factor influencing survival was the presence of nodes; however, this was not a significant factor in locoregional control.

CONCLUSION

High levels of locoregional control and survival have been achieved with the addition of chemotherapy to radiation treatment for high-risk MCC of the skin. The role of chemoradiotherapy for high-risk MCC warrants further investigation.

Oropharyngeal metastasis of a Merkel cell carcinoma of the skin

Merkel cell carcinoma (MCC) is an aggressive neuroendocrine tumor of the skin characterized by frequent local and regional recurrence, a high incidence of distant metastases and therefore a high mortality. Here, we report a case of an oropharyngeal metastasis of a Merkel cell carcinoma of the skin localized at the left base of the tongue causing dysphagia and the sensation of globus pharyngeus. The unusual metastatic site is presented, and diagnosis and treatment are discussed.

Merkel cell carcinoma--a retrospective analysis of 17 cases

OBJECTIVE

To report clinical experience with the rare neuroendocrine Merkel cell carcinoma of the skin.

SUBJECTS AND SETTING

Seventeen patients with Merkel cell carcinoma of the skin treated at the Departments of Dermatology and ENT, Krankenhaus Dresden-Friedrichstadt, Dresden, Germany, during the years 1984-2000 were evaluated.

METHODS

A retrospective analysis was performed. Age and sex distribution, clinical data and therapy were collected. Outcome measures including overall survival, tumour-free survival and relapse-free survival were determined.

RESULTS

Six male and 11 female patients with an age range of 68-90 years (mean age 73.3 years) were identified. The primary tumour localization was head and neck region (n = 8), upper limbs (8), lower limbs (1). Twelve patients presented in tumour stage I, three in stage II and one in stage III. First line therapy was complete surgical excision with wide margins in 16 patients followed by loco-regional radiation in 12 of 16 cases. In 16 patients follow up data were available. After primary treatment complete response was achieved in 14 of 16 patients (87.5%), two patients had a partial response. The median of relapse-free survival was 44 weeks [mean +/- standard deviation: (44 +/- 118) weeks]. The median of overall survival was 102 weeks [mean +/- standard deviation: (137 +/- 94) weeks]. Three patients with a PR after primary treatment had a median overall survival of only 48 weeks [mean +/- standard deviation: (51 +/- 20) weeks].

CONCLUSIONS

Primary surgical treatment with wide excision combined with radiotherapy seems to be a reasonable first-line treatment but prospective controlled multicentre trials are necessary for validation.

Is there a diminishing role for surgery for Merkel cell carcinoma of the skin? a review of current management

Merkel cell carcinoma is a highly malignant skin tumour that must be managed in a multidisciplinary forum. Excisional biopsy of the primary is recommended and this should be followed by postoperative radiotherapy to the primary site, in-transit areas and the draining lymph nodes. The tumour is quite radiosensitive and radiation doses of the order of 50 Gy offer high levels of local control. Resection margins of 3 cm are not required provided postoperative radiotherapy is used. In the event of inoperable disease, patient refusal of surgery or a frail patient, radiotherapy should be used as the sole treatment modality, with high likelihood of achieving local control. Patients with involved nodes have a higher risk of distant disease. Traditionally, involved nodes have been managed with resection but, currently, there are protocols exploring the use of synchronous chemoradiotherapy as definitive treatment. Although adjuvant chemotherapy has been used in this setting to reduce the risk of distant seeding, the benefits at this stage have not been confirmed conclusively. The presence of distant disease carries a grave outlook and responses to chemotherapy occur frequently, but are usually shortlived.

Merkel cell carcinoma in the setting of HIV infection

Merkel cell carcinoma has been found to have an increased incidence among immunosuppressed patients, specifically organ transplant recipients receiving immunosuppressive therapy. HIV similarly depresses the immune response of infected persons. We report a case of Merkel cell carcinoma (MCC) in an HIV-infected patient who died from liver metastases 2 years after his tumor was diagnosed. The purpose of this report is to describe the possible relationship between HIV and MCC and to emphasize the importance of early diagnosis and aggressive management of MCC.

Multimodality treatment of Merkel cell carcinoma: case series and literature review of 1024 cases

BACKGROUND

Merkel cell carcinoma (MCC) is an unusual and potentially aggressive cancer of the skin. There is no consensus regarding the optimal therapeutic approach, and the relative roles of surgery, radiotherapy, and chemotherapy still are controversial The aim of this study is to analyze the roles of these therapeutic options.

METHODS

The medical records of 16 patients with a diagnosis of localized, primary MCC treated at the University of Alabama at Birmingham were reviewed. An extensive review of the English-language literature also was performed. The Kaplan-Meier method was used to develop the survival curves. Comparisons were made using Fisher's exact test. Significance was defined as P < .05.

RESULTS

MCC presented primarily in Caucasians (98.3%) with a median age of 69 years. Immunosuppressive therapy appeared to play a role in the development of this cancer. In the UAB experience, 3-year actuarial survival was 31%. The only factor significantly associated with overall survival was the stage of disease at presentation: median survivals were 97 vs. 15 months for stages I and II, respectively (log-rank, P = .02). From the literature review, adjuvant radiotherapy was associated with a reduced risk of local recurrence (P < .00001).

CONCLUSIONS

MCC is an aggressive cancer, with a high tendency for local recurrence and distant spread. Surgery and adjuvant radiotherapy appear to provide optimal local control. The role of chemotherapy remains to be defined.

Merkel cell carcinoma: report of 10 cases and review of the literature

BACKGROUND

Merkel cell carcinoma (MCC) is a rare primary neuroendocrine skin tumor that usually arises in the head and neck or the extremities of elderly patients. Because of the limitation of retrospective data, optimal treatment is not well defined.

OBJECTIVE

Our purpose was to present the clinical course and treatment of 10 patients with MCC and review the published literature on MCC.

METHOD

We conducted a retrospective analysis and obtained detailed clinical information for all 10 patients treated for MCC at our institution from 1986 through 1998. The medical literature was also reviewed for natural history and treatment recommendations using MEDLINE search.

RESULTS

Five men and 5 women received their treatment between 1986 and 1998 for MCC (5 had stage IA disease, 4 stage IB, 1 stage II). The mean age was 70.3 years (range, 47-86 years). Seven tumors were located on the head and neck and 3 on extremities. Five of 10 patients had a relapse (mean time before recurrence, 5.7 months) (range, 2 weeks-20 months); one patient had local recurrence, one had regional lymph node recurrence, and 3 had both local and regional lymph node recurrence. In 4 patients systemic metastases developed. Long survival is also noted (6 to > 164 months); 4 patients died of MCC. After initial surgery, 9 patients received radiotherapy at some point and 3 patients also received chemotherapy. Five of 10 patients had 13 previously treated or coexisting malignant neoplasms. In one patient MCC developed in a previously irradiated field. Review of 875 cases showed a male/female ratio of 1.5:1; location of tumors was as follows: head and neck, 47%; extremities, 40%; trunk, 8%; unknown primary site, 5%. Local recurrence was observed in 25%, regional lymph node involvement in 52%, distant metastasis in 34%, and MCC was a cause of death in 34%.

CONCLUSION

MCC has a high incidence of locoregional recurrence with distant metastases that is more common with higher stage lesions. Early local management of smaller lesions results in good long-term survival. It is not known whether prophylactic lymph node dissection and/or radiation and adjuvant radiation increases survival. Long survival can be achieved after treating locoregional recurrence. The role of chemotherapy is still controversial and should be considered in patients with advanced disease and those not thought to be candidates for surgery.