Merkel Cell Carcinoma of the Eyelid

Merkel cell carcinoma and the eye

Merkel cell carcinoma (MCC) is a rare cutaneous neuroendocrine tumor with a poor five-year survival rate. Yearly cases have risen nearly 350% since the early 1980s, and these are predicted to increase as the overall US population ages. MCC of the eyelid is uncommon and can be misdiagnosed as other benign inflammatory and neoplastic eyelid disorders. Although MCC of the head and neck is often more aggressive than it is at other sites, eyelid MCC shows a lower disease-specific mortality rate. A biopsy is essential for accurate diagnosis, including an immunohistochemical panel of CK20 and TTF-1, although other markers may be necessary. Staging can be assessed clinically through physical examination findings and imaging and/or pathologically with sentinel lymph node biopsy or fine-needle aspiration. Pathologic staging more accurately predicts the prognosis. Eyelid MCC treatments include Mohs micrographic surgery to allow for complete clearance and adequate reconstruction of lost tissue, followed by adjuvant radiotherapy. In advanced disease, immunotherapies are preferred over traditional chemotherapy and are a subject of ongoing research.

An Effective Primary Treatment Using Radiotherapy in Patients with Eyelid Merkel Cell Carcinoma

BACKGROUND

Merkel cell carcinoma (MCC) is a rare type of neuroendocrine tumor. Palpebral localization represents 2.5% of MCCs. Surgery is not always possible due to the localization or comorbidities of elderly patients. We hypothesized that radiotherapy (RT) alone could be a curative treatment in patients contraindicated for oncological surgery.

METHODS

We performed a retrospective monocentric study of patients with localized eyelid MCC treated with curative intent using curative radiotherapy.

RESULTS

Overall, 11 patients with histologically confirmed eyelid MCC were treated with curative radiotherapy. The median age was 77 years old (range: 53-94). Curative RT was decided mainly due to difficult localization and significant co-morbidities. The median lesion dose was 57 Gy (range: 47-70). Most patients had adjuvant lymph nodes irradiation with a median dose of 50 Gy (n = 9; 82%). The median follow-up was 62 months (6-152 months). None of the seven deaths were MCC-related. None of our patients relapsed during follow-up. Side effects related to radiotherapy were mild (no grade ≥ 2) and rare (n = 3, 21%).

CONCLUSION

Our data suggest that curative radiotherapy is an effective and safe treatment for Merkel cell carcinoma of the eyelid and periocular region. Radiotherapy alone allows limiting the aesthetic and functional sequelae in elderly and comorbid patients who are contraindicated for oncological surgery.

Prevalence of Merkel Cell Polyomavirus in Primary Eyelid Merkel Cell Carcinomas and Association With Clinicopathological Features

PURPOSE

Merkel cell polyomavirus (MCPyV) infection is a known to be a critical risk factor for the development of Merkel cell carcinoma (MCC). Various reports on cutaneous MCC have shown that the differences in clinicohistopathological characteristics depend on the presence of MCPyV, but the situation in eyelid MCC is unknown. This study aimed to assess the prevalence of MCPyV in patients with eyelid MCC and examine the clinicohistopathological characteristics of MCPyV-associated eyelid MCC.

DESIGN

Retrospective observational case series with laboratory investigations.

METHODS

Ten patients treated for eyelid MCC were included. Histopathological characteristics were examined by immunohistochemical staining using 12 antibodies. MCPyV infection was evaluated by PCR using primer sets targeting large T antigens of the MCPyV genome and by immunohistochemical staining using CM2B4 and Ab3 monoclonal antibodies. The MCPyV viral load was also quantified by PCR using 3 primer sets.

RESULTS

All patients (4 males and 6 females) were Japanese with mean age of 79 (range: 63 to 87) years. One patient died due to distant metastasis 8 months after surgery for MCC. Immunohistochemical studies showed typical MCC findings in all cases, including CK20 and neuroendocrine marker positivity. PCR and immunohistochemistry with CM2B4 and Ab3 detected MCPyV antigen in all tumors. Quantitative PCR using sT, LT4, and TAg primers yielded 0.94, 1.72, and 1.05 copies per cell, respectively.

CONCLUSION

Clinical and histopathological characteristics of 10 patients with eyelid MCC were elucidated. MCPyV infection was detected in all eyelids. These results provide insight for understanding the tumorigenesis of eyelid MCC.

Merkel Cell Carcinoma of the Left Eyelid with Metastasis to the Left Submandibular Lymph Nodes: A Case Report and Brief Review

Merkel cell carcinoma (MCC) is a cutaneous cancer often found on sun-exposed areas. MCC is rare but very often lethal making early diagnosis challenging although critical. There are only a few cases that have reported MCC of the eyelid making it often hard to identify in clinic. A 52-year-old woman with a firm nodule on the left eyelid was diagnosed with MCC that had also metastasized to a left submandibular lymph node. She underwent surgical excision of the mass and lymph node as well as parotid gland and neck dissection to rule out other metastases and then underwent radiation therapy. The aim of this study is to report a case of eyelid MCC with metastasis to a local lymph node to provide another example of the rare cancer in hopes that diagnosis and treatment options for MCC are more thoroughly studied and understood.

Spontaneous regression of presumed ocular surface squamous neoplasia: A report of 8 cases

PURPOSE

To report the phenomenon of spontaneous regression in presumed ocular surface squamous neoplasia (OSSN).

METHODS

Retrospective chart review of clinically diagnosed cases of OSSN during 2016 to 2019.

RESULTS

Of the 449 OSSN lesions, spontaneous regression was seen in 8 lesions (2%). The mean age at diagnosis of OSSN was 37 years (median, 36 years; range, 21 to 59 years). All were males with unilateral, treatment-naïve tumors. Mean duration of symptoms was 3 months (median, 2 months; range, 1 to 12 months). All tumors arose within the interpalpebral region, located in the nasal quadrant in 88% (n = 7) and in temporal quadrant in 12% (n = 1). The mean tumor diameter was 4 mm (median, 4 mm; range, 3 to 5 mm). Lesions showed nodular (n = 4; 50%) or placoid (n = 4; 50%) morphology. The other features included keratin production and intrinsic vascularity (n = 8; 100%), feeder vessels (n = 4; 50%), and intratumoral pigmentation (n = 4; 50%). The diagnosis of OSSN was confirmed by classic anterior segment optical coherence tomography (AS-OCT) features. Tumors regressed after a mean period of 5 months (median, 4 months; range, <1 to 17 months) from presumed onset and a mean period of 2 months (median, 1 month; range, <1 to 6 months) from presentation to the clinic. No recurrences were noted at a mean follow up of 37 months (median, 35 months; range, 17 to 52 months) after spontaneous regression of tumors.

CONCLUSION

OSSN can spontaneously regress in 2% of cases. Immune-mediated reversal of dysplastic changes may explain this phenomenon.

PRÉCIS

In this study, spontaneous regression of presumed ocular surface squamous neoplasia was noted in 2% patients. Tumor regression resulted in restoration of normal epithelial architecture and no recurrences were observed during the follow-up period.

[Hordeolum and chalazion : (Differential) diagnosis and treatment]

Hordeolum and chalazion are the most frequent inflammatory eyelid tumors. They can occur in association with underlying diseases causing Meibomian gland dysfunction and/or chronic blepharitis. Due to the typical morphological features and clinical course, the diagnosis can mostly be clinically established. The majority of these lesions resolve spontaneously over time. In some instances, surgical intervention is unavoidable. In persistent, recurrent or clinically atypical cases malignant tumors must be excluded as a differential diagnosis by excisional biopsy and histopathological assessment.

Merkel cell carcinoma of the eyelid and periocular region: A review

Merkel cell carcinoma (MCC) is a rare primary cutaneous neuroendocrine carcinoma with a high mortality rate. It typically affects elderly Caucasians, with a slight predilection for males. It is associated with chronic sun exposure and/or immunosuppression. Almost half of all cases occur on the head or neck and an estimated 2.5%–10% arise on the eyelids or periocular skin. It ranks as the 5^th most common malignant tumor at these sites, preceded in frequency by basal cell, squamous cell and sebaceous carcinoma, as well as melanoma. Its clinical presentation as a violaceous nodule/plaque lacks specificity, and it can be mistaken for cysts, chalazia or basal cell carcinomas. Sub-specialized histopathological and immunohistochemical evaluations are required for diagnosis. Clinical staging defines the extent of disease and governs management. This includes surgery and adjuvant radiotherapy for localized tumors and of late, immunotherapy for metastatic disease. Significant advances in our understanding of the dual etiopathogenesis (Merkel cell polyomavirus- and Ultraviolet radiation-induced) and the biology of the neoplasm have been achieved in recent years. Issuing from the tumor's known susceptibility to host immunity, a recent therapeutic breakthrough has occurred whereby immune checkpoint inhibition has been shown to mitigate advanced disease. These factors and the increased global incidence of the tumor have brought it to the forefront of medical attention. This review provides a clinically relevant update on MCC, with special reference to cases arising on the eyelid/periocular region.

Spontaneous Tumor Regression in Tasmanian Devils Associated with RASL11A Activation

Spontaneous tumor regression has been documented in a small proportion of human cancer patients, but the specific mechanisms underlying tumor regression without treatment are not well understood. Tasmanian devils are threatened with extinction from a transmissible cancer due to universal susceptibility and a near 100% case fatality rate. In over 10,000 cases, <20 instances of natural tumor regression have been detected. Previous work in this system has focused on Tasmanian devil genetic variation associated with the regression phenotype. Here, we used comparative and functional genomics to identify tumor genetic variation associated with tumor regression. We show that a single point mutation in the 5' untranslated region of the putative tumor suppressor RASL11A significantly contributes to tumor regression. RASL11A was expressed in regressed tumors but silenced in wild-type, nonregressed tumors, consistent with RASL11A downregulation in human cancers. Induced RASL11A expression significantly reduced tumor cell proliferation in vitro The RAS pathway is frequently altered in human cancers, and RASL11A activation may provide a therapeutic treatment option for Tasmanian devils as well as a general mechanism for tumor inhibition.

The role of infectious agents in cancer of the ocular region

The purpose of the study was to investigate the association between infectious agents and the development of cancer in the ocular adnexa. A comprehensive literary study was carried out, reviewing and summarizing previous reports on the topic. A broad range of malignancies of the ocular adnexa are associated with infectious agents. A strong association and possible causal relationship between the infectious agent and the development of ocular adnexal cancer are seen in Merkel cell carcinoma (Merkel cell polyomavirus), Burkitt lymphoma (Epstein-Barr virus) and Kaposi sarcoma (human herpesvirus 8). Infection with Chlamydia psittaci has been associated with the development of extranodal marginal zone B-cell lymphoma in Italy. Human papillomavirus infection has been associated with the development of squamous cell carcinomas of the ocular adnexa, although with a highly variable reported prevalence. By exploring the role of infectious agents in the ocular adnexa and the mechanism by which they contribute to oncogenesis, the diagnostics, management and prevention of these malignancies may also improve. Antibiotic treatment and vaccines against infectious agents may be valuable in future treatment. Additionally, the presence of infectious agents within the tumours may have a prognostic or predictive value.

Upper eyelid Merkel cell carcinoma treated with neoadjuvant chemotherapy and surgical excision

Merkel cell carcinoma is a rare cutaneous carcinoma, featured by an aggressive clinical course and a mortality rate of 28% at 2 years. A 71-year-old female was affected by a 4.1-cm-wide locally advanced Merkel cell carcinoma of the upper eyelid, previously misdiagnosed as chalazion, with involvement of the extraocular muscles. Although the tumor showed a macroscopic spontaneous regression in size after the incisional biopsy, the mass was treated with neoadjuvant chemotherapy and surgical excision. Good functional and aesthetic result with preservation of the eyeball and absence of tumor recurrence were achieved at 3-year follow-up. In our experience, the combination of the inflammatory cascade due to the incisional biopsy and neoadjuvant chemotherapy led to the regression of a locally advanced large Merkel cell carcinoma of the eyelid.

Merkel cell carcinoma of the eyelid: A review

Merkel cell carcinoma (MCC) is a rare, aggressive tumor of both epithelial and neuroendocrine origin, which carries a mortality rate of up to 40%. MCC tumors typically present as painless, expanding nodules on the sun-exposed skin areas of older, white patients. Eyelid and periocular tumors comprise approximately 2.5% of all cases of MCC and may be mistaken for chalazia or basal cell carcinomas. Immunosuppression is a significant risk factor, particularly in solid-organ-transplant recipients, patients with chronic lymphocytic leukemia, and patients with HIV. Sentinel lymph node biopsy is often used for accurate staging of head and neck MCC. Treatment includes wide local excision, commonly with the addition of radiotherapy for improved locoregional disease control. Historically, adjuvant chemotherapy had been reserved for metastatic disease, but immunotherapy and targeted chemotherapies are currently being investigated for use in primary disease. The clinical characteristics of all available published cases of eyelid MCC are summarized in this article.

Regression of Sebaceous Carcinoma of the Eyelid after a Small Incisional Biopsy: Report of Two Cases

Purpose

To report 2 cases of regression of sebaceous carcinoma of the eyelid after a small incisional biopsy.

Methods

Clinical, imaging, and histopathological findings are presented, with a literature review on regressing ocular tumors.

Results

Our first patient was a 79-year-old man who presented with a 10-month history of progressive left upper eyelid ptosis caused by an eyelid tumor with orbital involvement and confirmed on magnetic resonance imaging. Our second patient was a 70-year-old woman who presented with ptosis with a left upper eyelid mass. Both patients underwent a small incisional biopsy of their lesion. The histopathological diagnoses in both cases were consistent with sebaceous carcinoma. Both patients refused exenteration. Follow-up clinical examination and imaging disclosed total regression of the ptosis and of the neoplasm with no sign of recurrence in both patients over a 4-year period for Case 1 and a 7-year period for Case 2.

Conclusion

Regression following incisional biopsy of basal cell, squamous cell, and Merkel cell carcinoma, including of the eyelid, is well documented. To the best of our knowledge, our 2 cases of sebaceous carcinoma are the first to be reported with total involution clinically and on imaging of the tumor following partial incisional biopsy.

The Genomic Basis of Tumor Regression in Tasmanian Devils (Sarcophilus harrisii)

Understanding the genetic basis of disease-related phenotypes, such as cancer susceptibility, is crucial for the advancement of personalized medicine. Although most cancers are somatic in origin, a small number of transmissible cancers have been documented. Two such cancers have emerged in the Tasmanian devil (Sarcophilus harrisii) and now threaten the species with extinction. Recently, cases of natural tumor regression in Tasmanian devils infected with the clonally contagious cancer have been detected. We used whole-genome sequencing and FST-based approaches to identify the genetic basis of tumor regression by comparing the genomes of seven individuals that underwent tumor regression with those of three infected individuals that did not. We found three highly differentiated candidate genomic regions containing several genes related to immune response and/or cancer risk, indicating that the genomic basis of tumor regression was polygenic. Within these genomic regions, we identified putative regulatory variation in candidate genes but no nonsynonymous variation, suggesting that natural tumor regression may be driven, at least in part, by differential host expression of key loci. Comparative oncology can provide insight into the genetic basis of cancer risk, tumor development, and the pathogenicity of cancer, particularly due to our limited ability to monitor natural, untreated tumor progression in human patients. Our results support the hypothesis that host immune response is necessary for triggering tumor regression, providing candidate genes that may translate to novel treatments in human and nonhuman cancers.

A case series of Merkel cell carcinoma of the eyelid: a rare entity often misdiagnosed

Merkel cell carcinoma (MCC) is one of the rarest eyelid tumors, with high mortality rate due to lymphatic and metastatic spread. We hereby report six cases of patients with histological diagnosis of MCC referred to our Orbit Unit between 2012 and 2018, focusing on diagnosis, treatment, and subsequent follow up. All patients underwent surgical excision and systemic work-up. Both MCC TNM and eyelid MCC TNM were used to stage lesions. MCC of the eyelid is usually misdiagnosed as benign or other malignant lesions. A prompt examination and a wide local excision are mandatory. A close follow-up of these patients is advised due to high recurrence rate and lymphatic spread.

Surgical Management of Periocular Cancers: High- and Low-Risk Features Drive Treatment

PURPOSE OF REVIEW

Recent advances in the treatment of eyelid tumors have centered on the excision, evaluation of margins, role of sentinel lymph node biopsy, and adjunctive/adjuvant systemic and radiation therapy. The purpose of this review is to elaborate on these advances.

RECENT FINDINGS

Mohs excision of basal cell carcinoma and squamous cell carcinoma continues to provide the greatest success in complete excision of the cancer, especially in those cases of high-risk disease including medial canthal location and recurrent disease. Sentinel lymph node biopsy has proven useful in the assessment of early regional metastasis in sebaceous cell carcinoma, melanoma, and Merkel cell carcinoma. The pathologic finding of perineural invasion is a high-risk feature in all periocular cancers, and adjuvant therapy should be considered. Targeted therapy shows great potential in situations that are not amenable to complete excision without sacrificing the globe. Identification of high- and low-risk features in eyelid cancers allows a stratified approach to treatment. While high-risk features may require adjuvant therapy, larger margins, and sentinel lymph node biopsy, low-risk features may allow topical therapy to adequately address the condition. Monoclonal antibodies and small molecule inhibitors show great promise in the treatment of extensive disease.

Sebaceous Carcinoma of the Eyelid

BACKGROUND

Periocular sebaceous carcinoma (PSC) is a rare but aggressive neoplasm that tends to clinically and histopathologically mimic other conditions. PSC can be challenging to diagnose using histomorphology alone given its overlap with 2 more common tumors that occur in this area (basal cell carcinoma [BCC] and squamous cell carcinoma [SCC]). Use of immunohistochemistry can help resolve this differential diagnosis.

METHODS

A review of the literature was performed, focusing on the epidemiology, morphology, and immunohistochemical features of PSC.

RESULTS

The most useful immunostains in the differential diagnosis of PSC are epithelial membrane antigen, Ber-Ep4, androgen receptor (AR), and adipophilin. To discern PSC from BCC, one should use EMA, Ber-Ep4, AR, and adipophilin, whereas discerning PSC from SCC can be achieved by evaluating AR and adipophilin. In addition, p53 and ERBB2 (formally known as HER2/neu) are other potentially useful immunohistochemical markers for the differential diagnosis of PSC.

CONCLUSIONS

Use of new immunohistochemical techniques, as well as the elucidation of molecular alterations, such as the presence of ERBB2 amplification, will advance our understanding of PSC.

Merkel cell carcinoma of the eyelid. A series of 5 cases and review of the literature

OBJECTIVE

Presentation of 5 clinical cases of Merkel cell carcinoma of the eyelid, highlighting the clinical, histopathological, management, and monitoring features. Review of related literature.

METHODS

Retrospective review of clinical records and telephone interview of the 5 patients treated for Merkel cell carcinoma between 2006 and 2013, in the Orbit and Oculoplastic Department, Clinical Hospital of the University of Chile.

RESULTS

Five patients (2 men, 3 women); 79.2 years (range 64-94 years), with a mean onset of 10 weeks (range 5-16 weeks), tumour size reaching a mean of 2.5×2×2.1cm at the time of surgery. Described as a nodular mass, exophytic, solid, reddish coloured. With no infiltrated lymph nodes or metastases in the first match. Staging as T2N0M0, after the first surgery with oncological criteria. Two lymph node recurrences detected during monitoring. Distant metastasis was found in one patient. The histopathological diagnosis was confirmed by immunohistochemical study of the biopsy. The surgical strategy was full excision, control of surgical margins in the intraoperative period, and eyelid reconstruction with Hughes flap, Cutler/Beard flap or primary closure, depending on the case.

CONCLUSIONS

Early diagnosis, wide excision of the tumour with intraoperative control of clear margins with conventional or Mohs surgery, and proper eyelid reconstruction are adequate for a good survival in elderly patients with this eyelid tumour. The study of sentinel lymph node biopsy in primary intervention is recommended; with subsequent radiotherapy to decrease the recurrence and increase survival.

Spontaneous Regression of Primitive Merkel Cell Carcinoma

Merkel cell carcinoma (MCC) is a rare, aggressive skin tumor that mainly occurs in the elderly with a generally poor prognosis. Like all skin cancers, its incidence is rising. Despite the poor prognosis, a few reports of spontaneous regression have been published. We describe the case of a 89-year-old male patient who presented two MCC lesions of the scalp. Following biopsy the lesions underwent complete regression with no clinical evidence of residual tumor up to 24 months. The current knowledge of MCC and the other cases of spontaneous regression described in the literature are reviewed.

Spontaneous regression and recurrence of stage III Merkel cell carcinoma

Merkel cell carcinoma (MCC) is a malignant neuroendocrine carcinoma originating in the skin. It is typically aggressive with a tendency to recur locally and metastasise. There have been several case reports about spontaneous regression of MCC over the past years, but to the best of our knowledge this is the first case of a regional lymph node metastasised MCC with complete spontaneous regression and recurrence. In addition, the primary tumour has an unusual localisation on the foot.

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

INTRODUCTION

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

PRESENTATION OF CASE

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

DISCUSSION

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

CONCLUSION

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

A rapidly growing lid lump

A 97-year-old woman presented with a 5-month history of a rapidly growing, painless, left upper eyelid lesion. Examination revealed a large vascularised, ulcerated nodule on the left upper lid, causing significant ptosis. Wide local excision of the lesion was performed and the wound was left to heal by secondary intention. Histology and immunohistochemistry of the lesion confirmed a diagnosis of Merkel cell carcinoma, a rare primary malignancy of the eyelid which has significant morbidity and mortality. Although uncommon, this diagnosis should always be considered in any patient with a rapidly growing lid lump. In view of the patient's age, known dementia and family wishes, the patient was managed conservatively, with no further investigations performed. She was due to be followed up in clinic on a regular basis, but has since died from other causes.

Merkel cell carcinoma of the eyelid and periocular region

Merkel cell carcinoma (MCC) in the eyelid and periocular region can be treated surgically, in most cases, with preservation of the eye and reasonable visual function. Adjuvant radiation therapy, sentinel lymph node biopsy, and chemotherapy should be considered for MCC of the eyelid and periocular region, especially for larger tumors that are T2b or more advanced and lesions that present with regional nodal or distant metastasis.

Primary neuroendocrine carcinoma of ocular adnexa

We present our findings in a case of primary neuroendocrine carcinoma (NEC) of the lacrimal gland and a case of primary Merkel cell carcinoma (MCC) of the eyelid. An 86-year-old man noticed a swelling of the left upper eyelid three months earlier. We performed excision biopsy and histopathological examination indicated that he had a primary NEC of the left lacrimal gland. He underwent chemotherapy followed by excision including the clinically visible margins and 50 Gy radiotherapy of the surgical margins. He had neither recurrence nor metastasis for 6 months since the last radiotherapy. An 80-year-old man noticed a nodule in the right upper eyelid and was referred to our hospital because the size was increasing rapidly. A complete surgical excision of the margins of the tumor was performed with histopathological confirmation of negative margins. The final diagnosis was a primary MCC of the right upper eyelid. After surgery, he underwent 50 Gy radiotherapy on the neck to prevent metastasis. No recurrence or metastasis was found for two years. Although primary NEC of the ocular adnexa is extremely rare, the tumor has high malignancy and readily metastasizes. Thus, combined therapy including surgery, radiotherapy, and/or chemotherapy is needed for complete management of NEC.

Merkel cell distribution in the human eyelid

Although Merkel cell carcinoma of the eyelid is reported frequently in the literature, only limited information exists about the distribution of Merkel cells in this tissue. Therefore, serial sections of 18 human cadaver eyelids (donors ages ranging between 63 and 97 years) were stained for cytokeratin 20 in various planes. The overall appearance of Merkel cells in these samples was low and mainly located in the outer root layer of the cilia hair follicles. Merkel cells were more frequent in the middle, and almost not detectable at the nasal and temporal edges. The localization is in accordance with that of Merkel cell carcinoma, but concerning the scarce appearance within this adulthood group, a specific physiological role of these cells in the eyelid is difficult to establish.

Unusual Merkel cell carcinoma of the eyelid

Merkel cell carcinoma of the eyelid is a rare tumor with less than 100 reported cases worldwide. We describe an unusual presentation of Merkel cell carcinoma of the eyelid in a 60 year old Asian male. He presented with multiple left lower lid conjunctival nodules, intense conjunctival erythema, as well as ipsilateral cervical lymphadenopathy. An incisional biopsy diagnosed him with Merkel cell carcinoma with a PET scan showing distant metastatic disease. He was then treated with chemotherapy. The combination of a presentation of conjunctival nodules and erythema, location in the lower eyelid and the conjunctiva, the presence of metastatic disease on diagnosis as well as an unusual immunohistochemical profile make this an unusual case.

A case of complete spontaneous regression of extremely advanced Merkel cell carcinoma

Merkel cell carcinoma (MCC) is a rare locally malignant cutaneous tumor of neuroendocrine origin, most often occurring on the head and neck of the elderly. MCC is a highly aggressive tumor with a high percentage of recurrence, metastatic spread and mortality. Despite the highly malignant course of MCC, there have been several reports of spontaneous regression or resolution. We report the clinical course of a 71-year-old man with MCC. The tumor initially occurred in the left lower eyelid and advanced to encompass nearly half the face. Despite its large size, complete spontaneous regression of the tumor occurred. This is the most advanced case of complete spontaneous regression of MCC to be reported.

Giant Merkel cell carcinoma of the eyelid: a case report and review of the literature

Merkel cell carcinoma (MCC) is a rare cutaneous tumor and cases located in the eyelid have been described, but still its rarity may lead to difficulty in diagnosis and delay in treatment. A 51-year-old female patient that presented with large lesions in the eyelid underwent surgery after the diagnosis of acute chalazion. Following respiratory distress secondary to pulmonary metastasis, the patient's condition deteriorated and was not fit for complete excision treatment. Histopathological investigation of the biopsies, taken from the tumor, revealed that it was undifferentiated small cell carcinoma. Our aim with this paper is to point out that more cases should be reported for more effective diagnosis, histopathological study, clinical investigation, treatment and prognosis of this specific neoplasm.