A rapidly growing lid lump

Abstract

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.

Background

We discuss a case of Merkel cell carcinoma (MCC), as a reminder of an important clinical lesson. Although MCC is a rare disease, it is an important differential to consider in any patient presenting with a rapidly growing lid lump. This is primarily due to the high risk of local and distant metastases, which confer significant morbidity and mortality.

Our report focuses on the presentation, diagnosis and management of this condition. We have included photomicrographs which show the histological and immunohistological staining appearances, which we feel is of significant educational value.

Case presentation

A 97-year-old woman with dementia presented to eye casualty with a 5-month history of a left upper lid lesion. She was brought in by her carers from the residential home, who had noticed the lump growing rapidly in the 3 weeks prior to presentation. There was no associated pain. The ocular history included primary open angle glaucoma (gel timolol 0.25% twice a day to both eyes) and a left branch retinal vein occlusion (not requiring any treatment).

Visual acuities were 6/36 and perception to light in the right and left eyes, respectively. The reduced left visual acuity was felt to be due to the significant left ptosis and her known history of primary open angle glaucoma. On examination, there was a 2.5 cm diameter solid nodule on the left upper lid, sparing only the medial third of the lid (figure 1). The nodule was red, vascularised and showed evidence of extensive ulceration. Extraocular muscle movements were full and with no evidence of a relative afferent pupillary defect. There was no abnormality of the right eyelids.

Figure 1.

Photograph of the left upper lid lesion.

Investigations

The type of skin cancer was unclear from clinical findings alone, but a provisional diagnosis of basal cell carcinoma was carried out, despite the fact that this would not be expected to grow so rapidly. However, the lesion was confirmed to be MCC by the histopathology, which showed a mostly endophytic lesion composed of nodules and diffuse sheets of basophilic cells, involving most of the dermis but sparing the epidermis (figure 2A). Invasion of tumour cells into lymphovascular spaces were present, with nuclear moulding and apoptotic debris. There was dot-like paranuclear positivity for CK20, which is seen in MCC (figure 2B).

Figure 2.

Photomicrographs showing a H&E-stained section of the excised lesion (A) and cytokeratin (CK) 20 immunohistochemical stain of the lesion (B).

Of note, immunohistochemical staining did not express S100 or thyroid-transcription factor-1 (TTF-1). This supported a diagnosis of primary cutaneous neuroendocrine carcinoma (MCC), rather than metastatic small cell carcinoma of the lung.

Differential diagnosis

Differentials for a rapidly growing painless, solid lesion on sun-exposed skin include: squamous cell carcinoma, sebaceous cell carcinoma, MCC, malignant melanoma and keratoacanthoma.

Treatment

Wide local excision of the left upper lid lesion was performed under local anaesthetic, which showed some tarsal plate buckling and distortion. The excised lesion was sent for histopathology and the wound left to heal by secondary intention (granulation). A decision not to use a skin graft was carried out to minimise the extent of interventional treatment required.

Outcome and follow-up

In this particular case, a decision was made to manage the patient conservatively, due to the patient's advanced age, dementia, multiple comorbidities and family's wishes. As such, she did not have any further investigations following excision of the MCC, but regular follow-up was planned. She has since, however, died from other causes.

Discussion

MCC is a rare and highly aggressive primary neuroendocrine carcinoma of the skin, which was first described in 1972. The estimated incidence of MCC is 0.23/100 000 person-years.¹ It appears to show a male predilection and is rare in patients younger than 50 years.^{2 3} Immunosuppressed patients appear to be more at risk of developing MCC.⁴ It has been reported that 35–47% of MCCs are found in the sun-exposed head and neck regions, with up to 5–10% occurring on the eyelids.¹

A case series of 195 patients revealed that the most common clinical features of MCCs could be summarised into the acronym ‘AEIOU’: Asymptomatic (lack of tenderness), Expanding rapidly in <3 months, Immune suppressed, Older than age 50, Ultraviolet exposed site on fair skin.⁵ It also showed that 89% of primary MCCs expressed three or more of these criteria.

The gold standard for the diagnosis of MCC is immunohistochemistry, as it allows differentiation from metastatic small cell carcinoma, small B-cell lymphoma and anaplastic small cell melanoma. CK20 has been shown to be a specific and sensitive marker for MCC and is the most widely used immunohistochemical stain for its diagnosis.⁶ Of note, MCC is usually negative for S100 (marker for melanoma) and TTF-1 (marker for metastatic small cell lung carcinoma).¹

Wide local excision (with margins of 1–2 cm) or Mohs’ micrographic surgery is usually the first step in management of MCC.⁷ Some centres also advocate adjuvant radiotherapy (50 Gy),⁸ which may reduce local recurrence rates.

Five-year survival rates for MCC are 75%, 59% and 25% for primary MCCs, lymph node metastasis and distant metastasis, respectively.⁶ Poor prognostic factors include tumour size >2 cm, high mitotic rate of tumour cells, lymph node or distant metastasis, previous immunosuppressive therapy and male gender.^{1 3 9} Of note, absence of lymph node disease has been reported to be the most consistent predictor of survival.¹⁰

Learning points.

• Malignancy should always be considered for any rapidly growing painless lid lesion, especially in patients over the age of 50.

• Merkel cell carcinoma is a rare primary lid malignancy.

• Distant metastasis commonly occurs in Merkel cell carcinoma with associated high mortality rates.

• Regular follow-up is essential, as Merkel cell carcinoma frequently recurs locally.