Overview of Canine Eyelid Tumors
The eyelid is a common site of tumor formation in dogs. Most eyelid tumors occur in middle-aged to older animals. The vast majority of eyelid tumors in the dog are benign.
Canine eyelid tumors often originate spontaneously from the glands located within the eyelid margin. Complete surgical removal is the recommended treatment and is usually curative.
Eyelid tumor enlargement can interfere with proper eyelid blinking and cause ocular irritation from rubbing of the tumor against the cornea. Conjunctivitis and increased ocular discharge are common in animals with growing eyelid tumors.
Not all nodules or masses of the eyelids are tumors. Certain types of inflammation may also mimic the appearance of eyelid tumors.
What to Watch For
Swelling and nodule or mass formation on the eyelid surface or along the eyelid margin
Ulcerated and reddened area on eyelid margin
Mucoid or pus-like discharge from the eye
Bloodshot or reddened conjunctiva
Cloudiness, bluish haze or film covering the cornea
Frequent pawing or rubbing of the eye
Minor bleeding from the eyelid
Increased blinking or squinting of the eyelids
Diagnosis of Eyelid Tumors on Dogs
Veterinary care includes diagnostic tests to determine the type of eyelid lesion and to direct subsequent treatment. Your veterinarian may recommend some of the following:
Complete medical history and physical examination
Complete ophthalmic examination including close examination of the eyelids, cornea, conjunctiva, and front chamber of the eye
Fluorescein staining of the cornea
Bacterial culture of secretions of the eye
Fungal culture and cytology (microscopic examination) of skin scrapings from around the eyelid
Fine needle aspirate of the eyelid tumor for cytology
Tissue biopsy of the eyelid tumor
Complete blood count and serum biochemistry
Chest X-rays to look for possible spread of the tumor
Treatment of Eyelid Tumors on Dogs
Treatments for eyelid tumors may include one or more of the following:
The recommended treatment for most canine eyelid tumors is surgical removal, using either a scalpel or laser. Complete excision is usually curative for the benign eyelid tumors.
Large eyelid tumors may require surgical reconstructive techniques of the skin and tissues around the eyelid to preserve adequate protection of the eye after tumor removal.
Certain types of eyelid tumors may respond to medical therapy if they are small and do not invade nearby tissues extensively. Small mast cell tumors (mastocytomas) may respond to systemic corticosteroids or locally injected corticosteroids. Lymphosarcoma of the eyelid may respond to chemotherapy, as this location of the tumor usually represents metastasis (spread) of systemic cancer from somewhere else in the body.
Certain types of tumors may respond to cryotherapy, which is freezing of the tumor.
If the tumor is large and invades the surrounding tissues, then surgical removal may also involve removal of the eye and permanent closure of the skin of the face and forehead.
Home Care and Prevention for Eyelid Tumors on Dogs
If an eyelid nodule or swelling is observed, call your veterinarian promptly. Immediate evaluation of the eyelid lesion is very important if accompanying symptoms of ocular discomfort are observed, such as increased blinking, tearing and redness of the eye.
Gently wipe away any eye discharge with a warm moist cloth as needed to keep the eyelid area clean. Do not allow the pet to rub or self-traumatize the eyelids. After diagnosis of an eyelid tumor, lubricating or antibiotic ointments may be prescribed until the time of surgical removal.
There is no preventive care for most types of eyelid tumors. It is well known that squamous cell carcinoma develops more commonly in dogs with pink or white eyelid margins that have prolonged sun exposure. Reducing sun exposure in these dogs by always allowing them shaded area may help to reduce the risk of developing this type of tumor.
Information In-depth for Canine Eyelid Tumors
The vast majority of eyelid tumors in the dog are benign. Malignant tumors tend to grow more rapidly than benign tumors and local invasion of surrounding tissues can be more extensive.
Canine eyelid tumors most often originate from the glands located within the eyelid margin. Sebaceous gland (meibomian) adenoma, squamous papilloma and benign melanocytoma represent the most commonly diagnosed eyelid tumors in the dog. Other less common benign tumors include the fibroma and histiocytoma. Complete surgical removal is usually curative for these tumors.
Malignant tumors that occur in the eyelid of dogs include the basal cell carcinoma, mast cell tumor, lymphosarcoma, malignant melanoma, squamous cell carcinoma, sebaceous adenocarcinoma (rare) and fibrosarcoma (rare).
The most important aspects of treating eyelid tumors are to determine the specific tumor type and the degree of local invasiveness and/or spread to other parts of the body. These two factors are essential to determine the most appropriate therapy for each animal.
A few other eyelid conditions can mimic the symptoms similar to those observed with eyelid tumors. It is important to exclude these conditions before establishing a conclusive diagnosis.
Hordeolum (stye). Styes represent bacterial infections or inflammation of the eyelid margin glands. They can appear as either a single abscess or multiple abscesses with swelling along the eyelid margins.
Chalazion. A chalazion is the retention and accumulation of material within one of the glands of the eyelid. Chalazia typically appear as smooth white, yellow or tan nodules along the inside rim of the eyelid margins. They may remain quiet and non-painful with little to no change in appearance, they may eventually decrease in size, or they may induce inflammation and increase in size.
Allergic blepharitis (inflammation of the eyelids). Ocular exposure to a contact allergen can result in a rapid onset of symptoms that include eyelid (conjunctival) swelling and redness. The eyelid condition may also be associated with a generalized allergic reaction of the body. This is most often seen after insect bites, drug reactions and as a post-vaccination reaction.
Autoimmune skin diseases. Certain autoimmune skin diseases can manifest as eyelid inflammation, swelling and ulceration. These include pemphigus foliaceus, pemphigus vulgaris, and pemphigus erythematosus. These diseases commonly affect the skin of the face, lips, nose pads, ears and eyelids.
Bacterial blepharitis. Inflammation of the eyelids is often caused by Staphylococcus and Streptococcus spp. of bacteria infecting the meibomian glands located within the eyelid margin. Abscesses form nodules along the eyelid margin. The infections can be long-standing and recurrent in nature. In puppies, this condition can be quite severe and cause considerable facial and eyelid swelling.
Parasitic blepharitis. Both demodectic and sarcoptic mange can involve the eyelids in dogs. In young dogs, the infection is commonly isolated to the face and eyelids. Typically these mites cause crusty, hairless lesions on the eyelids rather than nodule formation.
Mycotic (fungal) blepharitis. Ringworm can cause inflammation of the eyelids, but usually cause hairless and crusty lesions rather than the development of nodules or masses.
Cuterebra larvae. The Cuterebra fly may lay its eggs along the eyelid margin. After the eggs hatch, a large larval worm begins to grow under the skin and a slow growing mass may develop around it. The mass always has a small hole in the surface of the skin through which the larva breathes.
Granulomatous inflammation. Certain immune-mediated inflammations of the eyelids of dogs may form nodules that appear very similar to eyelid tumors. These include two rather unusual diseases: nodular granulomatous episcleritis and periadnexal multinodular granulomatous dermatitis. Both of these conditions may be accompanied by nodules in other locations, such as within the eye or skin.