Periocular Skin Cancers
Skin cancers on the eyelids or the skin around the eyes (periocular) account for between five to ten percent of all skin cancers. Ninety five percent of these tumours are basal cell carcinomas and squamous cell carcinomas. The incidence of skin cancers is increasing both for non melanoma skin cancers and melanomas.
Nonmelanoma skin cancers have low rates for spread to lymph nodes and to other parts of the body (metastasis). But there is a risk that eyelid skin cancers can damage neighbouring structures, including the eye, nose and eye socket.
Basal Cell Carcinoma
Basal cell carcinomas (BCCs) are found most commonly on the lower eyelid (50-60%), then the inner part of the eyelids, by the nose, (25-30%), less often on the upper eyelid (15%) and least commonly on the outer part of the eyelids (5%). Basal cell carcinomas can be classified by shape either as raised (nodular), raised and ulcerated (nodulo-ulcerative) and morpheaform. The first two types appear as solid nodules with a pearly appearance and fine, dilated blood vessels on the surface. The third sort are slightly raised areas of thickened skin which are poorly defined but usually behave in a more aggressive fashion. The best treatment for BCC is generally regarded to be surgery. Other treatments that can be used in patients who are not fit for surgery include cryotherapy and radiotherapy.
Squamous Cell Carcinoma
Squamous cell carcinomas (SCCs) are less common than BCCs but can behave in a more aggressive manner. They can appear very similar in appearance to BCCs but have much greater potential for metastatic spread to other parts of the body. Like BCCs, SCCs are best treated by surgical excision but they have a higher likelihood of recurring. Due to the possibility of spread to other parts of the body, it is sometimes necessary to check the lymphnodes which are associated with the affected area by taking a sample of the lymph nodes to look for signs that the tumour has spread.
Sebaceous Gland Carcinoma
Sebaceous gland carcinoma is a rare but highly malignant tumour which begins in the meibomian glands of the tarsal plate. Initially this tumour can look like a chalazion or an area of blepharitis, a BCC or an SCC. Like all malignant eyelid tumours, signs of eyelash loss or distortion of the appearance of the eyelid anatomy are warnings of a destructive, dangerous process which needs to be investigated. The definitive treatment for sebaceous gland carcinoma is surgery.
Merkel Cell Carcinoma
Merkel cell carcinoma is a rare but very malignant form of skin cancer, with approximately 60-70% of patients showing signs of spread of the tumour by the time they are first seen. Merkel cell carcinomas are usually found in women aged 70-80 years old. They appear as painless, purple coloured nodules which grow rapidly. Surgery is the mainstay of treatment, often with additional radiotherapy to the affected area.