The International Society for Orbital Disorders (I.S.O.D.): its pith and purport

Merkel cell carcinoma (trabecular cell carcinoma) is a rare, distinct, primitive, neuroendocrine malignancy of the skin, usually affecting elderly patients. It develops from Merkel cells and nearly one out of every 10 Merkel cell carcinomas occurs in the eyelids and periocular region. The tumor manifests itself clinically as a bulging lesion near the lid margin, painless, reddish colored with teleangiectatic blood vessels on the surface. Histologically, the tumor can mimic malignant lymphoma, undifferentiated melanoma, sebaceous carcinoma or cutaneous metastases of pulmonary microcytoma. Immunohistochemical studies with antibodies to neuron-specific enolase, cytokeratins and neurosecretory granules are necessary to differentiate these tumors. One third of all Merkel cell carcinomas result in death. In the present paper, we present data on the clinical features, treatment and long-term follow-up of three patients.     

Merkel cell carcinoma: a distinct lesion of the eyelid

Merkel cell carcinoma (trabecular cell carcinoma) is a rare, distinct, primitive, neuroendocrine malignancy of the skin, usually affecting elderly patients. It develops from Merkel cells and nearly one out of every 10 Merkel cell carcinomas occurs in the eyelids and periocular region. The tumor manifests itself clinically as a bulging lesion near the lid margin, painless, reddish colored with teleangiectatic blood vessels on the surface. Histologically, the tumor can mimic malignant lymphoma, undifferentiated melanoma, sebaceous carcinoma or cutaneous metastases of pulmonary microcytoma. Immunohistochemical studies with antibodies to neuron-specific enolase, cytokeratins and neurosecretory granules are necessary to differentiate these tumors. One third of all Merkel cell carcinomas result in death. In the present paper, we present data on the clinical features, treatment and long-term follow-up of three patients.     

The Merkel cell and associated neoplasms in the eyelids and periocular region

Merkel cells are clear oval cells in the epidermis and outer root sheaths of hair follicles, which are probably of epithelial origin, share ultrastructural features with neuroendocrine cells, and are found in association with touch receptors. In the eyelid, they occur singly in the epidermis and external root sheaths of hairs and eyelashes, and in specialized touch spots alternating with eyelashes. Their typical electron microscopical and antigenic features include dense-core granules, intranuclear rodlets, spinous processes, and a positive reaction for specific cytokeratins, epithelial membrane antigen, neuron-specific enolase, chromogranin and synaptophysin. Merkel cell carcinoma probably develops from precursor cells which give rise to keratinocytes and Merkel cells, and nearly one out of ten Merkel cell carcinomas occur in the eyelid and periocular region. They tend to be bulging lesions near the lid margin of elderly patients, reddish in color, and erythematous with telangiectatic vessels. The diagnosis is based on the frequent presence of neurofilaments and paranuclear aggregates of intermediate filaments in addition to features typical of normal Merkel cells. The tumor often mimics lymphoma or undifferentiated carcinoma and frequently invades lymphatic vessels. One third of Merkel cell carcinomas recur, almost two thirds give rise to regional node metastases, and up to one half metastasize widely and result in death. Initial treatment should be prompt and aggressive, with wide resection and routine postoperative irradiation. Although metastatic lesions often respond to radiation therapy and cytostatic drugs, these treatments are mainly of palliative value.     

Merkel cell carcinoma of the eyebrow extending into the orbit

BACKGROUND: Merkel cell carcinoma is a rare and aggressive cutaneous neoplasm with high local recurrence and metastatic rates. PURPOSE: To highlight an unusual presentation of a Merkel cell carcinoma. CASE REPORT: We report a large Merkel cell tumor in an 85-year-old woman. It extended from the eyebrow into the upper nasal orbit posterior to the equator of the eye globe. Local resection resulted in microscopically complete removal of the tumor. During follow-up (20 months) no local recurrence was noticed but there was a metastasis in a lymphatic nodule. CONCLUSIONS: Merkel cell carcinoma often presents in the eyelids and periorbital region. However, extension from the eyebrow deep into the orbit is unusual.     

Primary palpebral localization of a trabecular Merkel cell carcinoma (1 case)

We report one case of Merkel cell carcinoma. They commonly arise on the eyelids of elderly patients. Others localisations are on the skin of the pelvis. Clinical aspects, histological study, associating morphological aspect, ultra-structural and immuno-histo-chemical studies are characteristics enough to differentiate this tumor others tumors of the skin like cutaneous malignant lymphoma. The origin of this tumor is still discussed, but sure neuro-endocrinal. Possibility of visceral metastases on a small number of cases (6 to 8%) must be consider when treated. Total surgical ablation should be obtained.     

Eyelid merkel cell carcinoma: report of three cases

PURPOSE: To present three cases of Merkel cell carcinoma, a primary cutaneous neuroendocrine tumor that arises from Merkel cells, and to describe their clinical features, diagnosis, and management. METHODS: Case series. RESULTS: In only one case, the disease was clinically recognized. In the others, the diagnosis was confirmed by histology, and chalazion was initially suspected in one of them. Surgery was performed in all patients, and there was no evidence of metastatic disease. CONCLUSIONS: The rarity of eyelid Merkel cell carcinoma and the fact that it can simulate benign entities frequently lead to difficulties in diagnosis and a delay in the establishment of suitable therapy.     

Basaloid follicular hamartoma of the eyelid

An 86-year-old woman slowly developed a solitary 0.3 3 0.2-cm papule on the left lower eyelid. Complete excision disclosed a honeycombed lesion composed of interlacing basaloid strands unattached to the epidermis but rather extending into the dermis from a dilated hair follicle. The diagnosis was a solitary basaloid follicular hamartoma that can also occur in multiple, generalized, and inherited forms, sometimes with an associated systemic disease. The lesion exhibited a distinctive CD34-positive, mildly cellular myxoid stroma with many CK20-positive Merkel cells scattered within the basaloid cellular strands, which exhibited BCL-2 positivity only within the outermost cells bordering the stroma. These immunohistochemical features are the opposite of those displayed by basal cell carcinomas, which require more aggressive surgical management. Besides basal cell carcinomas, the differential diagnosis of basaloid follicular hamartoma includes fibrofolliculoma, tumor of the follicular infundibulum, poroma, and trabecular (Merkel cell) carcinoma.     

An unusual presentation of merkel cell carcinoma of the eyelid

Merkel cell carcinoma is a rare primary neuroendocrine tumor occurring on any part of the body. It usually presents as a firm, nontender, violaceous, or purple nodule located on areas of the body that have been exposed to sunlight. A 68-year-old female presented with a rapidly growing lesion on the left lower eyelid from 6 weeks. Examination showed a 4 cm diameter, exophytic, ovoid skin lesion of the left lower lid. Wide local excision of this lesion was followed by adjuvant chemotherapy. Histological examination of therapeutic frozen section of the lesion and the presence of neuroendocrine marker and cytokeratin markers established the diagnosis of Merkel Cell carcinoma. The follow-up at 8 months was uneventful. Merkel cell carcinoma can have an unusual presentation of a large, exophytic, oval lesion resembling a basal cell carcinoma. Merkel cell carcinoma has predilection for rapid spread; hence, in a case of lid lesions, a suspicion for this diagnosis should be kept in mind.     

Merkel cell turnour occurring simultaneously in the upper and lower eyelids

Purpose: To highlight an unusual presentation of two Merkel cell turnours in the same patient.
Result We report a case of two Merkel cell turnours occurring simultaneously in the upper and lower eyelids of an elderly woman, a unique occurrence. Wide local resection and reconstruction resulted in microscopic clearance of the tumours. Lymphatic spread was detected, a common feature. She had previously undergone excision of a similar lesion from the lower eyelid.
Conclusion: Merkel cell tumour is a rare turnour of the elderly that often locally recurs and metastasises early. Treatment consists of wide local excision with or without adjuvant radiotherapy. Juxtaposing lesions on the eyelids have not been previously reported. We postulate that this patient showed local recurrence and a new tumour of the upper eyelid simultaneously.     

Merkel cell carcinoma

Merkel cell carcinoma is a neuroendocrine tumor of the skin, originating from neuroendocrine cells. A case report of Merkel cell carcinoma, discovered in a 77-Year-old woman, was diagnosed and confirmed on a biopsy. Diagnostic and therapeutic orientations of this unusual but malignant tumor are described.     

Retinitis pigmentosa and the question of photoreceptor connecting cilium defects

Background: A generalized structural defect of the cilia in various tissues, including photoreceptor connecting cilium, has been postulated as occurring in some forms of retinitis pigmentosa (RP). However, the literature on ciliary abnormalities in RP contains contradictory findings.Methods: In this study the fine structure of photoreceptors from 17 RP donors including X-linked RP, X-linked RP carrier state, autosomal dominant RP and autosomal recessive RP was examined by electron microscopy.Results: Photoreceptor preservation was commonly observed even in the most advanced cases of the disease, especially in the perimacular area, in the proximity of the optic nerve and in the periphery. Primary ciliary defects, expressed as additional or missing microtubules, were found in none of the samples. Comparison of photoreceptors in normal and RP retinae showed thinner cilia in RP cells but no defect in the microtubule arrangements within the connecting cilium.Conclusion: Additional or missing microtubules in ciliated cells are not uncommon and have been reported in the literature and recorded in some studies of RP tissue. Such defects, however, are believed to be acquired rather than inherited abnormalities of cilia and were not observed in the photoreceptor connecting cilia of RP patients examined in this study. Thinning of the cilium may also be a secondary effect related to cell shrinkage early during apoptosis, which is postulated to be a common pathway in photoreceptor degeneration.     

Oculoplastic aspects of ocular oncology

It is estimated that 5–10% of all cutaneous malignancies involve the periocular region and management of periocular skin cancers account for a significant proportion of the oculoplastic surgeon''s workload. Epithelial tumours are most frequently encountered, including basal cell carcinoma, squamous cell carcinoma, and sebaceous gland carcinoma, in decreasing order of frequency. Non-epithelial tumours, such as cutaneous melanoma and Merkel cell carcinoma, rarely involve the ocular adnexae. Although non-surgical treatments for periocular malignancies are gaining in popularity, surgery remains the main treatment modality and has as its main aims tumour clearance, restoration of the eyelid function, protection of the ocular surface, and achieving a good cosmetic outcome. The purpose of this article is to review the management of malignant periocular tumours, with particular emphasis on surgical management.     

Immunohistochemical studies of Merkel cell carcinoma of the eyelid.

Merkel cell carcinoma of the eyelid is a rare malignant tumor. Immunohistochemical studies can be helpful in establishing the diagnosis of this tumor. We encountered a case of Merkel cell carcinoma of the eyelid and conducted an immunohistochemical analysis for clarification of its cell properties. The patient in this study was a 78-year-old man who noted a small mass on his right upper eyelid, which was subsequently removed. However, the lesion recurred and progressively enlarged. The results of a biopsy indicated the possibility of a highly malignant tumor. The lesion was removed by orbital exenteration. Merkel cell carcinoma was finally diagnosed by using light and electron microscopy. In immunohistochemical studies, the tumor cells showed both neuron-specific enolase and cytokeratin. Most of the cells were also labeled with antibodies against the protein gene product 9.5, endocrine granule constituent and chromogranin A. However, no neuropeptides were labeled. The properties of the tumor cells appeared virtually the same as those of normal human Merkel cells.     

Merkel cell tumor of the eyelids: review of the literature and report of 2 patients

BACKGROUND: The Markel cell carcinoma is a rare malignant skin tumor. The tumor was first described in 1972 by Toker and he named it trabecular carcinoma. We had the opportunity to treat two patients with a Merkel cell carcinoma of the upper and lower eyelid and reviewed the literature using the "Medline" database concerning Merkel cell carcinomas of the ocular adnexa. HISTORY AND SIGNS: A 76-year-old female patient was referred to our hospital because of an inflammatory tumor of the left upper eyelid present for two months. A 91-year-old male patient noticed for four weeks a painless itching lesion at the left lower eyelid. The remaining ophthalmologic examination in these patients was unremarkable. THERAPY AND OUTCOME: Both tumors were excised. Histological and immunohistochemical examination verified a Merkel cell carcinoma in both cases. The 76-year-old female patient exhibited no recurrent tumor after a follow-up of 18 months. The 91-year-old male patient had a recurrent tumor inferior to the temporal lower eyelid 7 months after tumor excision, however, lymph node metastasis is not present as of yet. The patient underwent radiation therapy with cobalt of the left orbit with a total dose of 60 Gy. CONCLUSION: Merkel cell carcinomas can occur everywhere on the skin; the eyelids are affected in 10% of all cases. Best histochemical markers are cytokeratin 20 and neurospecific enolase. A review of the literature revealed 31 patients with Merkel cell carcinomas involving the eyelids. Female patients were more often affected than male patients. The upper eyelid was more frequently involved than the lower eyelid. Recurrent disease is frequent.     

A case of Merkel cell carcinoma of the eyelid

An 84-year-old man with Merkel cell carcinoma in the right upper-eyelid is reported. The patient presented with a rapidly growing, reddish-purple, solid tumor with a relatively well-defined margin in the skin of the lid. Increased neuron specific enolase content in the blood returned to normal several months after resection of the tumor and 70 Gy postoperative cobalt radiation. Histopathologic examination of the resected specimen revealed that the tumor was limited by intact epidermis and occupied by moderate-sized, round malignant cells with marked mitoses and scant cytoplasm. The neoplastic cells were positively stained by labeled antibodies for neuron specific enolase, keratin and epithelial membrane antigen. Electron microscopic examination showed abundant perinuclear microfilaments and dense core granules.     

Cutaneous Pseudolymphoma: An Unusual Eyelid Presentation

Pseudolymphoma is an inflammatory response to known or unknown stimuli that results in a lymphomatous-appearing but benign accumulation of inflammatory cells. Resemblance to lymphoma is usually most apparent histologically. Most cases are idiopathic. Approximately three-quarters of cases of cutaneous pseudolymphoma are localized with the most common site on the face (70%), chest, and upper extremities.

We would like to report an unusual eyelid presentation of cutaneous pseudolymphoma, not previously reported. It is therefore important to consider cutaneous pseudolymphoma as a differential diagnosis of eyelid lesions.     

Cutaneous pseudolymphoma: an unusual eyelid presentation

Pseudolymphoma is an inflammatory response to known or unknown stimuli that results in a lymphomatous-appearing but benign accumulation of inflammatory cells. Resemblance to lymphoma is usually most apparent histologically. Most cases are idiopathic. Approximately three-quarters of cases of cutaneous pseudolymphoma are localized with the most common site on the face (70%), chest, and upper extremities. We would like to report an unusual eyelid presentation of cutaneous pseudolymphoma, not previously reported. It is therefore important to consider cutaneous pseudolymphoma as a differential diagnosis of eyelid lesions.     

Metastatic Merkel cell carcinoma to the eye

Merkel cell carcinoma is an infrequent but highly aggressive cutaneous neoplasm. Previous reports of ocular involvement have included primary eyelid carcinomas, eyelid and orbital metastases, and a clinically diagnosed choroidal metastasis. The authors report the histopathologic documentation of a metastatic lesion to the ciliary body, confirming the intraocular metastatic potential of this tumor.     

Merkel cell carcinoma of the eyelid and periocular tissues.

Five patients had eyelid and periocular Merkel cell carcinoma. The tumor was located on the left lower eyelid in two patients, the left upper eyelid in one patient, the right upper eyelid in one patient, and was metastatic to the right outer canthus in one patient. The mean duration of symptoms was approximately four months. The diagnosis of Merkel cell carcinoma was not suspected clinically in any of the four primary eyelid cases, but was only established on histopathologic examination of biopsy specimens. Light microscopy disclosed carcinoma with small primitive cells in all five tumor biopsy specimens. Immunohistochemical studies showed neuron-specific enolase and keratin and transmission electron microscopy demonstrated neurosecretory granules typical for Merkel cell carcinoma. All five patients in this study were treated with wide surgical excision of the eyelid tumors with intraoperative frozen-section monitoring of the margins of resection. The left lower eyelid Merkel cell carcinoma spread to the preauricular lymph node in one patient. This patient subsequently died of metastatic Merkel cell carcinoma. One patient with metastatic right outer canthus Merkel cell carcinoma received radiotherapy (6,550 cGy). Eyelid Merkel cell carcinoma has the potential for recurrence and metastatic spread. We recommend lifetime follow-up for patients treated for eyelid Merkel cell carcinoma.