Merkel Cell Carcinoma Metastases to Caruncle With Orbital Extension: Report and Literature Review

Merkel cell carcinoma (MCC) is an uncommon and aggressive skin cancer of neuroendocrine origin. The tumor usually presents with a locoregional spread and most frequently metastasizes to the skin, liver, bone, lung, and brain. Despite the orbit being a relatively common site of metastases, it has rarely been reported in patients with MCC. The authors present a case of biopsy-proven orbital metastatic MCC in an 86-year-old male who presented with a rapidly enlarging right caruncle/subconjunctival mass with orbital extension and a history of forearm MCC excision 3 years prior. There are only 3 reported cases of distant metastatic MCC to the orbit, all presenting as a mass originating from extraocular muscles; and no cases of caruncle involvement.

Merkel cell carcinoma: a forty-year experience at the Peter MacCallum Cancer Centre

BACKGROUND

Merkel cell carcinoma (MCC) is a rare but highly aggressive neuroendocrine skin malignancy, with Australia having the highest reported incidence in the world. There is currently a lack of consensus regarding optimal management of this disease.

METHODS

This was a retrospective audit conducted by reviewing existing medical records of MCC patients presenting to the Peter MacCallum Cancer Centre (PMCC) between 1980 and 2018. The primary endpoint was locoregional recurrence. The secondary endpoints were distant recurrence, disease-free survival (DFS) and overall survival (OS).

RESULTS

A total of 533 patients were identified. Locoregional recurrence occurring at one, two and 5 years was 24, 31 and 32%, respectively. The estimated 5-year OS and DFS were 46% (95% Confidence Interval [CI] 41-51%) and 34% (95% CI 30-39%) respectively. Older age at diagnosis (hazard ratio [HR] per year = 1.07, 95% CI 1.06-1.07, p < 0.001), and larger primary tumour diameter (HR =1.16, 95% CI 1.03-1.31, p = 0.019) were associated with worse OS on multivariable analysis. Positive or negative histopathological margin status was not associated with OS or DFS differences in patients treated with post-operative radiotherapy.

CONCLUSIONS

In our study, about a third of patients developed locoregional recurrence, distal recurrence or both, and there appears to be no change over the last four decades. If treated with adjuvant radiotherapy, there is no difference in OS or DFS with positive surgical margins. Findings should influence future guidelines.

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.

Benefits and Limitations of a Multidisciplinary Approach in Cancer Patient Management

Over the years, a growing body of literature has confirmed as beneficial the implementation of a multidisciplinary approach in the so-often-intricate scenario of cancer patients' management. Together with the consolidation of tumor-board experience in clinical practice, certain aspects have emerged as controversial and a source of current debate. In this systematic literature review, we focused our attention on the impact of multidisciplinary tumor boards, assessing benefits and limitations as a result of the dissemination of such approaches. On the bright side, adherence to clinical guidelines, treatment outcomes, and overall improvement in decision-making processes have been recognized as advantages. On the other side, our analysis highlights a few limitations that should be taken into account to optimize cancer patients' management. Of note, some issues, such as costs, legal responsibility, geographic barriers, and treatment delays, have yet to be resolved. In order partly to address this matter, software platforms and novel methods of computational analysis may provide the needed support. Therefore, the aim of our analysis was to describe the multidisciplinary approach in cancer care in terms of adherence to clinical guidelines, treatment outcomes, and overall improvement in decision-making processes through a systematic review of the literature.

Merkel Cell Carcinoma Treatment in Finland in 1986-2016-A Real-World Data Study

Merkel cell carcinoma (MCC) is a rare cutaneous carcinoma that has gained enormous interest since the discovery of Merkel cell polyoma virus, which is a causative oncogenic agent in the majority of MCC tumours. Increased research has focused on effective treatment options with immuno-oncology. In this study, we reviewed the real-world data on different treatments given to MCC patients in Finland in 1986-2016. We used the Finnish Cancer Registry database to find MCC patients and the Hospital Discharge Register and the Cause-of-Death Register to obtain treatment data. We identified 376 MCC patients and 33 different treatment entities and/or combinations of treatment. An increase was noted in the incidence of MCC since 2005. Therefore, the cohort was divided into two groups: the "early" group with time of diagnosis between years 1986 and 2004 and the "late" group with time of diagnosis between 2005 and 2016. The multitude of different treatment combinations is a relatively new phenomenon; before the year 2005, only 11 treatments or treatment combinations were used for MCC patients. Our data show that combining radiation therapy with simple excision provided a survival advantage, which was, however, lost after adjustment for stage or age. Our registry study serves as a baseline treatment efficacy comparison as we move into the age of immunotherapy in MCC. Standardizing the treatment of MCC patients in Finland requires more work on awareness and multidisciplinary co-operation.

Merkel cell carcinoma of the forehead area: a literature review and case report

BACKGROUND

Merkel cell carcinoma (MCC) is an uncommon, aggressive malignancy of the skin, mostly affecting head and neck area in elderly white patients. Between head/neck sites, face accounts for 61% and forehead accounts for 17% of all face MCCs.

PURPOSE

We here present a literature review MCC cases arising in the forehead area, published in the English literature in the period 1987-2018, and report a personal observation with a late diagnosis and a treatment out of the current recommendations. The aims of this paper are to provide an up-to-date on MCC arising in the forehead area and to raise awareness about misdiagnosis of this type of lesion mimicking arteriovenous malformations (AVM).

MATERIAL AND METHOD

Literature review was performed on PubMed and Medline database and "Merkel cell carcinoma (MCC)," "forehead" and "MCC forehead location" were the terms the authors searched for. Patients' data have been drawn from descriptions of single cases and of short case series reports. For each case, data were collected about clinical characteristics, treatment modalities and outcomes. The study has been limited to the clinical features of the disease, excluding etiologic/pathogenic aspects.

RESULTS

Twenty-five patients with forehead MCC have been identified, coming from 20 sources. Nineteen presented a locoregional disease and 6 had an advanced pathology. TNM classification was reported in only two cases lacking for the other available data. Patients presented at mean age of 66 years with solitary or multiple nodules or dome-shaped/hemispherical mass, rarely ulcerated. Mean size of tumors was 1.13 cm of max diameter. Previous or concurrent malignancies or immune-hematologic disorders (AIDS) were often associated. At first investigation, lesion was often mistaken for other malignant or benign processes and, then, diagnosis was generally late. Some type of preoperative biopsy was performed in 3 patients, while the others had only a postoperative microscopic study of specimen. Initial treatment consisted in 6 cases (24%) in a not further specified about extent and width of margins local excision of the primary lesion, while a wide resection was reported in only 3 cases (12%). Surgical treatment of involved lymph-nodes was performed in 3 cases (12%). Six patients underwent radiotherapy for locoregional or distant recurrences. Mortality and overall survival rate at five years were 28% and 24%, respectively. Spontaneous regression was observed in 3 patients (12%).

CASE REPORT

Personal observation concerned an 82-year-old woman presenting with a forehead periorbital 5 × 5 cm red-bluish mass. The erythematous lesion was erroneously diagnosed as hemangioma on the base of color, the absence of any signs of malignancy, an angio CT indicating a hypervascular tissue and a FNA cytology (FNAC) lacking of malignant cells. The mass was excised as a benign lesion with about 1 cm margins extent without searching larger edges. Postoperative radiotherapy was offered to the patient after histology report, but she refused. After 4 months from surgery, she had a parotid metastasis and died from the illness in spite of platinum-based chemotherapy.

CONCLUSIONS

This study confirms the aggressiveness of forehead MCC, comparable with that of other face similar tumors. Personal case suggests that the deceitful benign feature of lesion may mimic an AVM and that FNAC may be misleading and diagnostic failure worsen prognosis. Our experience suggests that in the face smaller than 2-3 cm margins resection may increase the risk of locoregional recurrence. Therefore, postoperative wide-field irradiation should be ever delivered, after forehead MCC surgery, not only when clear margins are unattainable or involved with tumor, but also when negative microscopic edges are documented and residual cancer is thought not persist in the tumor bed. Orbit irradiation seems to be not dangerous for the eye.

A Report of 13 Cases of Merkel Cell Carcinoma: Single-Center Experience and Review of the Literature

Background

There is limited data knowledge of Merkel cell carcinoma (MCC) in Turkey aside from a few case reports.

Objective

The aim of this study was to describe the clinical characteristics, demographic features, therapeutic parameters, and outcome of primary cutaneous MCC cases from Turkey.

Methods

Digital medical records of the 13 MCC patients who were followed-up at a tertiary referral center were retrospectively analyzed. Clinic, demographic, tumor characteristics, and survival of the patients were retrieved.

Results

Most of our patients were elderly. Female predominance was noticed. The most common primary site of the tumors was the lower extremities. The overall survival was 42 months, 68% at first year, 68% at third years, and 29% at fifth years.

Conclusion

This is the first largest report from Turkish population with female predominance, and lower extremity tendency.

S2k guidelines for Merkel cell carcinoma (MCC, neuroendocrine carcinoma of the skin) - update 2018

Merkel cell carcinoma (MCC, ICD-O M8247 / 3) is a rare malignant primary skin tumor with epithelial and neuroendocrine differentiation. The neoplastic cells share many morphological, immunohistochemical and ultrastructural characteristics with Merkel cells of the skin. The diagnosis of MCC is rarely made on clinical grounds. Histological and immunohistochemical studies are usually required to confirm the clinical suspicion. Given the frequent occurrence of occult lymph node metastasis, sentinel lymph node biopsy should be performed once distant metastasis has been ruled out by cross-sectional imaging. Primary tumors without evidence of organ metastases are treated with complete surgical excision with appropriate surgical margins. Radiation therapy should be considered at all stages of the disease. For advanced MCC that is no longer amenable to curative treatment by surgery or radiation therapy, there is currently no established systemic therapy for which an improvement in recurrence-free survival or overall survival has been demonstrated in a prospective randomized trial. However, immunotherapy using PD-1/PD-L1 blockade seems to be superior to chemotherapy. Various factors warrant that further diagnostic and therapeutic interventions be determined by an interdisciplinary tumor board. These factors include the tumor's aggressiveness, the frequent indication for sentinel lymph node biopsy along with the frequent occurrence in the head and neck region, the potential indication for adjuvant radiation therapy as well as the complexity of the required diagnostic workup.

Survival Impact of Time to Initiation of Adjuvant Radiation for Merkel Cell Carcinoma: An Analysis of the National Cancer Database

PURPOSE

This study aimed to determine the impact of time to initiation (TTI) of adjuvant radiation therapy (RT) on overall survival (OS) for patients with stage I or II Merkel cell carcinoma (MCC).

METHODS AND MATERIALS

The National Cancer Database was queried for patients with MCC of the head and neck, trunk, or extremities diagnosed between 2006 and 2014. Patients who did not undergo resection or receive adjuvant RT within 180 days of surgery were excluded. TTI was defined as the time from resection to first RT fraction. Linear regression was used to define factors associated with TTI. Recursive partitioning analysis modeling was performed to determine an optimal threshold for TTI. Cox proportional hazards modeling was performed to define covariates associated with OS.

RESULTS

A total of 2293 patients were included in this study. The median TTI for the cohort was 62 days (interquartile range, 43-86 days). TTI was not associated with OS for the overall cohort by multivariable Cox modeling (P = .19). Age, treatment facility type, lymph node examination, anatomic subsite, and surgical margin were associated with TTI (P < .05). Age, sex, insurance status, Charlson-Deyo comorbidity score, lymph node examination status, tumor size, and surgical margin were associated with OS (all P < .05).

CONCLUSIONS

Increased TTI of adjuvant RT was not associated with OS for patients with early stage MCC in this analysis of the National Cancer Database. The median TTI of 62 days from resection to adjuvant RT initiation for our study cohort contextualizes TTI on a national level and may offer reassurance for patients with prolonged postoperative wound healing or intercurrent illness delaying immediate RT initiation. Despite the lack of a clear detriment to survival with increased TTI up to 180 days from surgery, unnecessary delays in initiating adjuvant therapy should continue to be minimized while ensuring optimal recovery from resection.

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.

Prognostic factors in Merkel cell carcinoma patients undergoing sentinel node biopsy

INTRODUCTION

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

METHODS

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

RESULTS

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

CONCLUSIONS

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

Postoperative radiation therapy is associated with a reduced risk of local recurrence among low risk Merkel cell carcinomas of the head and neck

PURPOSE

Merkel cell carcinoma (MCC) is a rare and often aggressive skin cancer. Typically, surgery is the primary treatment. Postoperative radiation therapy (PORT) is often recommended to improve local control. It is unclear whether PORT is indicated in patients with favorable Stage IA head and neck (HN) MCC.

METHODS AND MATERIALS

We conducted a retrospective analysis of 46 low-risk HN MCC cases treated between 2006 and 2015. Inclusion criteria were defined as a primary tumor size of ≤ 2 cm, negative pathological margins, negative sentinel lymph node biopsy, and no immunosuppression. Local recurrence (LR) was defined as tumor recurrence within 2 cm of the primary surgical bed and estimated with the Kaplan-Meier method.

RESULTS

Omission of PORT was offered to all 46 patients, of which 23 patients received PORT and 23 did not. No patient received adjuvant chemotherapy. There were no significant differences in surgical margins, tumor size, depth, lympho-vascular invasion status, or demographics between the two patient groups. Median follow-up for all patients was 3.7 years. Six of the 23 patients who did not receive PORT developed an LR. Compared to the group that received PORT, there was a significantly higher risk of LR in the group treated without PORT (26% vs. 0%, P = .02). Median time to LR was 11 months. All local failures were effectively salvaged. There was no difference in MCC-specific and overall survival between the 2 groups.

CONCLUSIONS

For patients with HN MCC, omission of PORT was associated with a significantly higher risk of local recurrence even among those patients with the lowest-risk tumors (i.e., Stage IA without immune suppression). Thus, it is important to weigh the benefits of PORT against the side effect profile on a case-specific basis for each patient.

Adjuvant Radiation Therapy and Chemotherapy in Merkel Cell Carcinoma: Survival Analyses of 6908 Cases From the National Cancer Data Base

BACKGROUND

Merkel cell carcinoma (MCC) has a high risk of recurrence after initial surgical therapy. Adjuvant radiation therapy (RT) and chemotherapy may be used to reduce the risk of locoregional and systemic recurrence, respectively, but there are conflicting data regarding their impact on survival. We performed a retrospective analysis of MCC cases from the National Cancer Data Base (NCDB) to assess whether adjuvant therapy was associated with differences in survival.

METHODS

Six thousand nine hundred and eight MCC patients with staging, treatment, and survival data were included. Multivariable analyses were conducted for overall survival (OS) with various treatment modalities while adjusting for prognostic variables including age, sex, comorbidities (Charlson/Deyo score), margin status, primary tumor site and size, and lymph node status. All statistical tests were two-sided.

RESULTS

For localized MCC (stage I: n = 3369, stage II: n = 1474 ), surgery plus adjuvant RT was associated with statistically significantly better OS than with surgery alone in multivariable analyses (stage I: hazard ratio [HR] = 0.71, 95% confidence interval [CI] = 0.64 to 0.80, P < .001; stage II: HR = 0.77, 95% CI = 0.66 to 0.89, P < .001). In patients with regional nodal metastases (stage III: n = 2065 ), neither adjuvant RT nor chemotherapy was associated with statistically significantly improved or worsened OS.

CONCLUSIONS

In this study of the largest MCC cohort reported to date, adjuvant RT was associated with improved OS in stages I-II MCC. Neither adjuvant RT nor chemotherapy was associated with improved OS in stage III MCC. These results, with the limitations of retrospective analyses, are consistent with earlier studies suggesting benefit with adjuvant RT but do not support the routine use of adjuvant chemotherapy in MCC.

Sentinel lymph node biopsy in Merkel cell carcinoma: a 15-year institutional experience and statistical analysis of 721 reported cases

Merkel cell carcinoma (MCC) is a rare aggressive cutaneous neuroendocrine malignancy that frequently metastasizes to the regional lymphatic basin. Pathological assessment of regional lymph nodes with sentinel lymph node biopsy (SLNB) in patients without clinical involvement has permitted more accurate staging and more appropriate management. Nonetheless, concerns have been raised regarding the accuracy of this technique and its prognostic implications. We conducted a review of previously published data analysing the positive and false negative rates of SLNB in MCC. A search of the Medline and Embase databases to April 2015 identified 36 published studies between 1997 and 2015 comprising 692 patients. With the addition of 29 patients treated at our own institution, we conducted an analysis of 721 patients. Among this cumulative cohort, SLNBs were performed from 736 regional sites with 29·6% recorded as positive. Regional metastasis occurred in 45 cases following a negative SLNB, for a false negative rate of 17·1%. Adjuvant regional radiotherapy in the setting of a negative SLNB did not affect regional recurrence (P = 0·31), providing credence to emerging evidence that regional therapy can be safely omitted in the setting of a negative SLNB. Distant relapse was noted far more frequently following a positive rather than negative SLNB (17·6% vs. 7·3%, P < 0·001).

Both tumor depth and diameter are predictive of sentinel lymph node status and survival in Merkel cell carcinoma

BACKGROUND

The purposes of this study were 1) to determine the impact of primary tumor-related factors on the prediction of the sentinel lymph node (SLN) status and 2) to identify clinical and pathologic factors associated with survival in Merkel cell carcinoma (MCC).

METHODS

An institutional review board-approved, retrospective review of patients with MCC treated between 1988 and 2011 at a single center was performed. Patients were categorized into 5 groups: 1) negative SLN, 2) positive SLN, 3) clinically node-negative but SLN biopsy not performed, 4) regional nodal disease without a known primary tumor, and 5) primary MCC with synchronous clinically evident regional nodal disease. Factors predictive of the SLN status were analyzed with logistic regressions, and overall survival (OS) and disease-specific survival (DSS) were analyzed with Cox models and competing risk models assuming proportional hazards, respectively.

RESULTS

Three hundred seventy-five patients were analyzed, and 70% were male; the median age was 75 years. The median tumor diameter was 1.5 cm (range, 0.2-12.5 cm), and the median tumor depth was 4.8 mm (range, 0.3-45.0 mm). One hundred ninety-one patients underwent SLN biopsy, and 59 (31%) were SLN-positive. Increasing primary tumor diameter and increasing tumor depth were associated with SLN positivity (P = .007 and P = .017, respectively). Age and sex were not associated with the SLN status. Immunosuppression, increasing tumor diameter, and increasing tumor depth were associated with worse OS (P = .007, P = .003, and P = .025, respectively). DSS differed significantly by group and was best for patients with a negative SLN and worst for those with primary MCC and synchronous clinically evident nodal disease (P = .018).

CONCLUSION

For patients with MCC, increasing primary tumor diameter and increasing tumor depth are independently predictive of a positive SLN, worse OS, and worse DSS. Tumor depth should be routinely reported when primary MCC specimens are being evaluated histopathologically.

Regional nodal relapse in surgically staged Merkel cell carcinoma

PURPOSE

The nodal relapse pattern of surgically staged Merkel cell carcinoma (MCC) with/without elective nodal radiotherapy (RT) was studied in a single institution.

METHOD

A total of 51 patients with MCC, 33% UICC stage I, 14% II, 53% III (4 lymph node metastases of unknown primary) were eligible. All patients had surgical staging: 23 patients sentinel node biopsy (SNB), 22 patients SNB followed by lymphadenectomy (LAD) and 6 patients LAD. In all, 94% of the primary tumors (PT) were completely resected; 57% of patients received RT, 51% of known PT sites, 33% (8/24 patients) regional RT to snN0 nodes and 68% (17/27 patients) to pN+ nodes, mean reference dose 51.5 and 50 Gy, respectively. Mean follow-up was 6 years (range 2-14 years).

RESULTS

A total of 22% (11/51) patients developed regional relapses (RR); the 5-year RR rate was 27%. In snN0 sites (stage I/II), relapse occurred in 5 of 14 nonirradiated vs. none of 8 irradiated sites (p = 0.054), resulting in a 5-year RR rate of 33% versus 0% (p = 0.16). The crude RR rate was lower in stage I (12%, 2/17 patients) than for stage II (43%, 3/7 patients). In stage III (pN+), RR appeared to be less frequent in irradiated sites (18%, 3/14 patients) compared with nonirradiated sites (33%, 3/10 patients, p = 0.45) with 5-year RR rates of 23% vs. 34%, respectively.

DISCUSSION

Our data suggest that adjuvant nodal RT plays a major role even if the sentinel nodes were negative.

CONCLUSION

Adjuvant RT of the lymph nodes in patients with stage IIa tumors and RT after LAD in stage III tumors is proposed and should be evaluated prospectively.

Prognostic significance of sentinel lymph node mapping in Merkel cell carcinoma: systematic review and meta-analysis of prognostic studies

Aim. To assess through a systematic review and meta-analysis of the literature the prognostic implication of sentinel lymph node mapping in Merkel cell carcinoma (MCC). Materials and Methods. PubMed and SCOPUS databases were searched by using “Merkel AND sentinel” as keywords. All studies with prognostic information regarding SLN mapping in cN0 MCC patients were included. Hazard ratio (HR) for overall survival (OS) and disease free survival (DFS) was used as effect size. Results. SLN biopsy predicted better DFS and OS as compared to the nodal observation in cN0 MCC patients (pooled HR for DFS: 1.61 (95% CI: 1.05–2.46), P = 0.028; pooled HR for OS: 1.08 (95% CI: 0.55–2.10), P = 0.8). Pathologically negative SLN (SLN−) patients had better OS (pooled HR: 4.42 (95% CI: 1.82–10.7), P = 0.0009) and DFS (pooled HR: 2.58 (95% CI: 1.78–3.73)) as compared to SLN+ patients. Conclusion. SLN mapping can provide strong prognostic information regarding OS and DFS in cN0 MCC patients. More importantly, SLN mapping can improve DFS and possibly OS in cN0 MCC patients as compared to nodal observation. As MCC is a rare tumor, large multicenter prospective studies are still needed to validate the survival benefit of SLN mapping.

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

BACKGROUND

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

METHOD

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

RESULTS

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

CONCLUSION

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

Merkel cell carcinoma

Merkel cell carcinoma (MCC) is a rare, clinically aggressive cutaneous neuroendocrine neoplasm with a high mortality rate. Though the etiology is not precisely known, Merkel cell polyomavirus DNA has been found recently in a large percentage of MCC tumors. Other suggested risk factors include sun exposure, immunosuppression, and a history of prior malignancy. Work up of patients with MCC most notably includes nodal staging via clinical examination or sentinel lymph node biopsy. The prognosis for most patients with MCC is poor, and the rarity of MCC precludes the prospective, randomized clinical trials necessary to elucidate optimum treatment protocols. Most published data support the use of a multimodality approach centered around surgical excision with negative margins, sentinel lymph node biopsy to establish the presence or absence of nodal metastases, adjuvant radiothearpy to decrease the risk of recurrence, and systemic chemotherapy in the case of widespread disease.

Evidence-based management of primary and localized Merkel cell carcinoma: a review

BACKGROUND

Merkel cell carcinoma is a rare and often lethal cutaneous neuroendocrine malignancy with a tendency for early and frequent locoregional and distant metastasis and relapses. It is a tumor of the elderly and immunosuppressed, which most often appears on sun-exposed areas of the body. There is growing interest in characterization of the disease and the best approach to its management. Despite the lack of prospective randomized clinical trials, treatment is evolving.

OBJECTIVE

To provide an updated review of the most current and relevant data concerning the surgical (± radiological) management of Merkel cell carcinoma, including the role of Mohs micrographic surgery.

METHODS

Using relevant MeSH terms, we performed a review of the literature on the above subjects from 1981 to 2011.

RESULTS AND CONCLUSION

For primary tumors without evidence of organ metastases, surgical excision should be the primary therapy. Owing to the high rate of local metastases, a safety margin of at least 2 cm should be considered. In situations where small, localized tumors and/or special locations necessitate a smaller safety margin, compensation by complete histological examination of the excision margins and perhaps adjuvant radiation therapy should be undertaken. The literature states that benefits of Mohs micrographic surgery (over wide local excision) include tissue conservation and identification of tumors that may require extremely wide excision margins. The majority of data to date supports the use of Mohs surgery in the treatment of Merkel cell carcinoma.

Sentinel lymph node biopsy in nonmelanoma skin cancer patients

The management of lymph nodes in nonmelanoma skin cancer patients is currently still debated. Merkel cell carcinoma (MCC), squamous cell carcinoma (SCC), pigmented epithelioid melanocytoma (PEM), and other rare skin neoplasms have a well-known risk to spread to regional lymph nodes. The use of sentinel lymph node biopsy (SLNB) could be a promising procedure to assess this risk in clinically N0 patients. Metastatic SNs have been observed in 4.5-28% SCC (according to risk factors), in 9-42% MCC, and in 14-57% PEM. We observed overall 30.8% positive SNs in 13 consecutive patients operated for high-risk nonmelanoma skin cancer between 2002 and 2011 in our institution. These high rates support recommendation to implement SLNB for nonmelanoma skin cancer especially for SCC patients. Completion lymph node dissection following positive SNs is also a matter of discussion especially in PEM. It must be remembered that a definitive survival benefit of SLNB in melanoma patients has not been proven yet. However, because of its low morbidity when compared to empiric elective lymph node dissection or radiation therapy of lymphatic basins, SLNB has allowed sparing a lot of morbidity and could therefore be used in nonmelanoma skin cancer patients, even though a significant impact on survival has not been demonstrated.

A practical update of surgical management of merkel cell carcinoma of the skin

The role of surgeons in the treatment of Merkel cell carcinoma (MCC) of the skin is reviewed, with respect to diagnosis and treatment. Most of the data in the literature are case reports. Surgery is the mainstay of treatment. A wide local excision, with sentinel node (SLN) biopsy, is the recommended treatment of choice. If SLN is involved, nodal dissection should be performed; unless patient is unfit, then regional radiotherapy can be given. Surgeons should always refer patients for assessment of the need for adjuvant treatments. Adjuvant radiotherapy is well tolerated and effective to minimize recurrence. Adjuvant chemotherapy may be considered for selected node-positive patients, as per National Comprehensive Cancer Network guideline. Data are insufficient to assess whether adjuvant chemotherapy improves survival. Recurrent disease should be treated by complete surgical resection if possible, followed by radiotherapy and possibly chemotherapy. Generally results of multimodality treatment for recurrent disease are better than lesser treatments. Future research should focus on newer chemotherapy and molecular targeted agents in the adjuvant setting and for gross disease.

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.

Merkel cell carcinoma: 30-year experience from a single institution

BACKGROUND

Merkel cell carcinoma (MCC) is a rare cutaneous malignancy. Few single-institution series have been reported.

METHODS

Review of MCC patients treated at our institution between 1980 and 2010. Patient, tumor, and treatment variables were analyzed to determine MCC-specific outcomes.

RESULTS

We identified 161 patients with MCC. There was a 2.5-fold increase in cases over the last decade. Median length of follow-up was 36 months. Stage at diagnosis was I in 35 %, II in 21 %, IIIa in 12 %, IIIb in 23 %, and IV in 9 %. The 5-year MCC-specific survival rates were 87, 63, 42, and 0 % for stages I, II, III, and IV, respectively. Death from the disease occurred in 10 % of patients with T1 and in 50 % with larger lesions. One-third of patients presented with nodal disease. Sentinel lymph node biopsy (SLNB) identified micrometastases in 9 out of 27 (33 %) early-stage patients. Recurrence developed in 56 % of SLNB-positive and 39 % of SLNB-negative patients. Half of patients recurred after a median time of 9 months. Proportions of first recurrence location were distant (52 %), nodal (27 %), and local (21 %). Adjuvant treatments did not improve recurrence or survival rates. One-third of patients died of the disease.

CONCLUSIONS

SLNB identifies micrometastasis in one-third of early-stage patients. Negative SLNB may predict for improved but not necessarily favorable outcome. Initial tumor size and clinical nodal disease predict for poor outcome. High recurrence rates warrant the development of more effective adjuvant therapies, and better markers of recurrence and treatment response for MCC are needed.

The role of free tissue transfer in merkel cell carcinoma of the head and neck

Merkel cell carcinoma (MCC) is an uncommon neuroendocrine malignancy with a propensity for the head and neck. It typically presents asymptomatically in elderly Caucasians and is characterized by early local and regional spread. There is currently limited data on the appropriate algorithm for treatment of MCC. However, multimodal therapy with wide surgical excision with or without radiation therapy has become standard of care. The location of the primary tumor and intensive adjuvant therapy is often required, provides a challenge to the reconstructive head and neck surgeon. Occasionally, free tissue transfer reconstructive techniques are employed in the reconstruction of MCC defects. This paper will discuss the role of free tissue transfer as a reconstructive option after surgery for advanced head and neck MCC.

Merkel cell carcinoma: identification of prognostic factors unique to tumors located in the head and neck based on analysis of SEER data

OBJECTIVES/HYPOTHESIS

Merkel cell carcinoma (MCC) is an aggressive cutaneous neoplasm that occurs most frequently in the head and neck region. Because of its rarity, prognostic factors are poorly characterized. Head and neck MCC (HN-MCC) may require separate consideration from MCC that occurs in other anatomic regions. Our objective was to determine the relevance of clinicopathologic parameters as prognostic factors in a large series of patients with HN-MCC and to compare these to a series of patients with non-head and neck MCC (NHN-MCC).

STUDY DESIGN

Retrospective analysis of large population database.

METHODS

Patients with MCC were identified using the Surveillance, Epidemiology, and End Results database and categorized according to tumor location either 1) within or 2) outside of the head and neck region. Clinicopathologic data were compared between groups. Retrospective univariable and multivariable analyses of factors associated with disease-specific survival (DSS) were performed.

RESULTS

We identified 2,104 patients with HN-MCC and 2,272 with NHN-MCC. DSS was similar between groups. Independent prognostic factors in HN-MCC are male sex (P < .001), lip primary site (P = .005), tumor extension beyond the dermis (P = .03), histologically confirmed nodal disease (P < .001), absence of histologic lymph node evaluation (P = .01), and distant metastasis (P = .001). Male sex and tumor extension limited to the subcutis are prognostic factors that are unique to HN-MCC.

CONCLUSIONS

Because independent markers of aggressive disease appear to be unique in HN-MCC, it is important that future studies provide separate consideration for HN-MCC to allow for the most accurate identification of prognostic indicators and assessment of treatment outcomes accordingly.

Five hundred patients with Merkel cell carcinoma evaluated at a single institution

OBJECTIVE

To identify factors associated with survival in Merkel cell carcinoma (MCC).

BACKGROUND

Merkel cell carcinoma is a rare cutaneous neoplasm. Staging and treatment are based on studies, which incompletely characterize the disease.

METHODS

Review of a prospective database was performed. Overall survival (OS) was estimated by the Kaplan-Meier method. Disease-specific death (DSD) was analyzed by the competing risks method. Factors associated with OS and DSD were determined by the log-rank test and Gray's test, respectively.

RESULTS

A total of 500 patients with MCC treated at our institution from 1969 to 2010 were identified. Eighty-eight patients presented older than 6 months after diagnosis and were excluded from further analysis. Of the remaining 412 patients, the median age at diagnosis was 71 years. Median follow-up was 3 years. Fifty percent of patients died during follow-up: 25% died of disease, 24% died of other causes. Five-year OS and DSD were 56% and 30%, respectively. Pathologic stage and lymphovascular invasion were independent predictors of DSD. Patients with metastatic disease (stage 4) or clinically positive lymph nodes (stage 3b) had increased DSD compared with patients with microscopically positive (stage 3a) or negative lymph nodes (stage 1 and 2). There was no difference in DSD between stage 3a or 2 compared with stage 1. Importantly, only 1 of 132 patients without lymphovascular invasion died of MCC.

CONCLUSIONS

OS is a poor measure of the influence of MCC on life expectancy. The presence of lymphovascular invasion and clinically, but not microscopically, positive lymph nodes were associated with increased DSD. These factors should be incorporated into MCC staging and treatment recommendations.

Recurrence after complete resection and selective use of adjuvant therapy for stage I through III Merkel cell carcinoma

BACKGROUND

Merkel cell carcinoma (MCC) is a rare cutaneous neuroendocrine neoplasm whose natural history is poorly understood. Here, the authors describe their experience with a large cohort of patients who were treated at a single institution to describe patterns of recurrence after curative therapy.

METHODS

Review of a prospective database was performed. Patient-related, tumor-related, and treatment-related variables were recorded, and the site and timing of initial recurrence were recorded. Factors associated with receipt of adjuvant therapy and recurrence were determined.

RESULTS

In total, 364 patients with stage I through III MCC who underwent complete resection were identified. Adjuvant local radiation therapy (RT), lymph node RT, and chemotherapy were received selectively by 23%, 23%, and 15% of patients, respectively. Factors associated with the receipt of adjuvant therapy included younger age, primary tumor features (larger size, lymphovascular invasion [LVI], positive margin excision), and increasing pathologic stage. With median follow-up of 3.6 years, 108 patients (30%) developed a recurrence, including 11 local recurrences (3%), 12 in-transit recurrences (3%), 43 lymph node recurrences (12%), and 42 distant recurrences (12%). Clinically involved lymph nodes, primary tumor LVI, and a history of leukemia/lymphoma were predictive of recurrence. The majority of recurrences (80%) occurred in patients who had clinically involved lymph nodes or patients who did not undergo pathologic lymph node evaluation.

CONCLUSIONS

A low recurrence rate in patients with clinically lymph node-negative MCC was achieved with adequate surgery (including sentinel lymph node biopsy) and the selective use of adjuvant RT for high-risk tumors. In contrast, patients with clinically lymph node-positive MCC had significantly higher rates of recurrence, especially distant recurrence. The authors concluded that contemporary natural history studies are critical in designing treatment pathways and clinical trials for MCC.

Recurrence and survival in patients undergoing sentinel lymph node biopsy for merkel cell carcinoma: analysis of 153 patients from a single institution

BACKGROUND

Merkel cell carcinoma (MCC) is a cutaneous neuroendocrine neoplasm with propensity for lymphatic spread. The rarity of MCC has limited analysis of factors associated with a positive sentinel lymph node biopsy (SLNB) and survival.

METHODS

Review of a prospective MCC database was performed. Factors associated with SLNB positivity were analyzed. Univariate and multivariate analyses of factors associated with recurrence and survival were performed using the cumulative incidence (CI) function, treating death from other causes as a competing risk.

RESULTS

From 1996 to 2010, a total of 153 patients with localized MCC underwent SLNB, of whom 45 (29%) were positive. Factors associated with SLNB positivity were primary tumor size (25% ≤2 cm vs. 45% >2 cm; P = 0.02) and presence of lymphovascular invasion (LVI) (55% LVI positive vs. 4% LVI negative; P < 0.01). SLNB-positive patients were more likely to receive radiation or chemotherapy (60% vs. 7%, P < 0.01). With median follow-up of 41 months, there were 16 nodal/distant recurrences (10%), 11 deaths from MCC (7%), and 27 death from other causes (18%). The 2-year CIs of recurrence or death from MCC were 12% and 6%, respectively. There was no difference in recurrence or death from MCC between SLNB-positive and -negative patients. The 2-year CIs of recurrence or death from MCC for LVI-positive patients were 30% and 15%, respectively. No LVI-negative patient experienced recurrence of disease or died of MCC.

DISCUSSION

SLNB identifies occult nodal metastases in 29% of patients with localized MCC. Predictors of SLNB positivity are tumor size and presence of lymphovascular invasion (LVI). Patients with SLNB-positive disease are more likely to receive further treatment; however, sentinel lymph node (SLN) status is not associated with recurrence or survival. In contrast, LVI is strongly associated with both recurrence and survival.