Basal
cell carcinoma is the most common malignancy of the eyelid, accounting for over
ninety percent of all cancerous lid lesions. Often, this tumor is discovered during
routine slit lamp evaluation. There is usually no associated pain or
discomfort. Basal cell carcinoma is more common in older, fair-skinned
individuals, especially with a history of prolonged or excessive exposure to
sunlight. The lower lid margin and medial canthus are the most common areas
involved.
The
basal cell lesion presents in one of three ways: (1) the nodular form appears
as a small, translucent, raised area with poorly defined edges, and is firm to
the touch; (2) the classic ulcerative presentation is a nodular lesion that
over time has developed telangiectasia (a reddish hue caused by persistent, and
virtually permanent, dilation of capillaries) along the surface and an
atrophied inner portion, creating a "pearly," indurated outer margin
with an excavated center; and (3) less frequently, the sclerosing or
morpheaform basal cell carcinoma form, which has a firm, pale, waxy yellow
plaque with indistinct borders.
While
there is no single known cause for all forms, there is a distinct association
with increasing age and exposure to ultraviolet radiation. In addition,
Caucasians have a much greater chance of developing basal cell carcinoma than
other races. The progression of this tumor is, in most cases, exceedingly slow.
If left untreated, however, the lesion may in time invade deeper structures.
Fortunately, metastasis is rare, and complete recovery is possible with proper
therapy.
Management
Basal
cell carcinoma is rarely life-threatening because of its non-metastatic,
slow-growing nature. However, this tumor does possess the capacity, over time,
to cause significant local destruction, and must always be treated
appropriately. Early biopsy is often the key to diagnosis. Biopsy all
suspicious lid lesions which demonstrate irregular growth, changes in color or
appearance, or purulent or bloody discharge to rule out cancer. Once the
diagnosis of basal cell carcinoma is confirmed, it can be treated with surgical
excision or radiation therapy. The preferred course for most cases is surgery,
with broad margins to ensure complete removal. When this can not be achieved,
local radiation therapy can also manage basal cell carcinoma well.