Eyelid Tumors in Cats

Feline Eyelid Tumors

Eyelid tumors are less common in cats than they are in dogs, and are more often malignant. Squamous cell carcinoma (SCC) is the most frequent type of eyelid tumor in the cat. The prevalence of SCC is higher for white cats, especially for older, outdoor cats with prolonged sun exposure.

Lymphosarcoma and mast cell tumors (mastocytoma) are the next most common tumors that affect the feline eyelid. In certain animals, both tumor types may get smaller with medical therapy.

Eyelid tumor enlargement can interfere with proper eyelid blinking and cause irritation of the eye from rubbing of the tumor against the cornea (the clear surface of the eye). Conjunctivitis and eye discharge are common in cats with growing eyelid tumors.

Not all nodules or masses of the eyelids are tumors. Some fungal infections can form small nodules on the eyelids and 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.
• Excessive tearing
• 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 in Cats

Veterinary care often 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 from 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
• Feline leukemia virus and feline immunodeficiency virus testing
• Chest X-rays to look for possible spread of the tumor

Treatment of Eyelid Tumors in Cats

Treatments for eyelid tumors may include one or more of the following:

• The recommended treatment for many eyelid tumors of the cat is surgical removal. This can be often be accomplished by removing a portion of the eyelid along with the tumor and then suturing the remaining eyelid back together.
• 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. This is particularly true of large squamous cell carcinoma tumors of the eyelid.
• Certain types of eyelid tumors may respond to medical therapy. Small mast cell tumors (mastocytomas) may respond to systemic corticosteroids or locally injected corticosteroids. Lymphosarcoma of the eyelid may respond to chemotherapy, as this site can represent metastasis of systemic cancer.
• Certain types of tumors may respond to cryotherapy, which is freezing of the tumor. This therapy may be considered for some small mast cell tumors, small and confined squamous cell carcinomas, and selected other tumors.
• 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

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 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 measures for most types of eyelid tumors. It is well known that squamous cell carcinoma develops more commonly in cats that have pink or white eyelids and are exposed on a regular basis to bright sunlight. Reducing sun exposure in these cats by keeping them indoors may help to reduce the risk of developing this type of tumor.

In-depth Information About Eyelid Tumors in Cats

Squamous cell carcinoma (SCC) is the most common type of eyelid tumor in the cat. The prevalence of SCC is higher for white cats, especially for older, outdoor cats with prolonged sun exposure. Local invasion of eyelid tissues by this tumor can be extensive, and metastasis, which is spread of the tumor to distant body sites, occurs in advanced stages of the disease. Multiple local treatment options are available when SCC is diagnosed in the early stages of disease.

Lymphosarcoma and mast cell tumors (mastocytomas) are the next most common tumors that affect the feline eyelid. Medical therapy is available for both tumor types and may induce regression of the tumor.

Other forms of malignant tumors that occur in the eyelids of cats include basal cell carcinoma, fibrosarcoma, neurofibrosarcoma and melanoma.

The most important aspect of treating eyelid tumors is 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 plan for treating the cat.

• 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 for several months before either decreasing in size or returning to the more active form.
• Fungal granuloma. A systemic fungal infection called histoplasmosis may cause the development of small nodules along the eyelid margin. They can appear very similar to eyelid tumors.
• Fungal blepharitis. Ringworm can causes inflammation of the eyelids, but usually causes hairless and crusty lesions rather than the development of nodules or masses.
• Bacterial blepharitis. Inflammation of the eyelids is often caused by Staphylococcus and Streptococcus spp. of bacteria. These bacteria infect the meibomian glands located along the eyelid margin. Abscesses in these glands may form nodules along the eyelid margin. Chronic infections can have a similar appearance to chalazia of the eyelids.
• Parasitic blepharitis. Mites such as demodex, notedric, and sarcoptic mange can involve the eyelids in cats. In young cats, the infection is commonly isolated to the face and eyelids. Typically these mites cause crusty, hairless lesions on the eyelids rather than nodule formation.
• 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.
• Eosinophilic blepharitis. This is a rare form of inflammation of the eyelid in which small nodules form that are filled with eosinophils, which are a type of white blood cell. The cause of this condition is unknown in the cat.

In-Depth Information about Diagnosis of Eyelid Tumors in Cats

Diagnostic tests are performed to determine the cause for the eyelid nodule/swelling, verify that the lesion is of a specific tumor type, define the degree of local invasion of the tumor and determine if the eyelid tumor will spread. The following tests are often recommended:

• Complete medical history and physical examination including palpation of regional lymph nodes for evidence of enlargement and auscultation of the chest. Historically, it is important to ascertain the duration of the eyelid lesion, the incidence of any prior tumors (anywhere in the body), and any accompanying physical symptoms of disease.
• Complete ophthalmic examination includes close examination of the eyelids, cornea, conjunctiva, and front chamber of the eye. This examination helps to delineate the boundaries and local extent of the eyelid tumor. The conjunctiva and cornea are examined for evidence of irritation caused by the eyelid tumor.
• Fluorescein staining of the cornea is performed to check for the presence of corneal erosions and ulcerations.
• Bacterial culture of secretions from the eye may be done to determine the presence and type of bacteria.
• Fungal culture and microscopic examination of skin scrapings from around the eyelid can be done to assess the presence of ringworm and parasitic mites.
• Fine needle aspirate of the eyelid tumor for cytology (complete cell analysis) can help to classify the type of tumor in some cases. Because cells are difficult to retrieve from some tumors, this test may be inconclusive. In such instances a tissue biopsy is needed to reach a diagnosis.
• Tissue biopsy of the eyelid tumor is the definitive way to establish a diagnosis of the tumor type.
• Complete blood count and serum biochemistry can evaluate other organ functions and search for evidence of infection or certain types of malignant cancers such as lymphosarcoma.
• Feline leukemia virus (FeLV) and feline immunodeficiency virus (FIV) testing may be recommended. Cats positive for FeLV are at increased risk for developing lymphosarcoma. Cats that are FIV positive are at increased risk for spontaneous tumor formation and infections.
• Cytology of cell aspirates from enlarged regional lymph nodes may be considered to assess for the presence of tumor spread or metastasis.
• Thoracic (chest) and abdominal radiographs are performed to determine the presence and extent of tumors that are suspected to be metastatic.

In-Depth Information about Treatment of Eyelid Tumors in Cats

With respect to treatment eyelid tumors may be divided into two types, those that can be managed with medicines and those that require surgery. Most eyelid tumors in cats require surgery, and the surgery may be followed by the application of certain topical medications.

In the early stages of eyelid tumor development, clinical evidence of eye discomfort or irritation is often not evident. Invariably, as eyelid tumors enlarge, they result in irritation to the surface of the eye and interfere with adequate blinking resulting in discharge. The ocular irritation caused by enlarging eyelid tumors may be difficult to treat medically until the eyelid tumor can be treated and removed surgically.

Medical Management

• Certain types of eyelid tumors may respond to medical therapy, particularly if they are small and have not invaded nearby tissues. Small mast cell tumors (mastocytomas) may respond to systemic or locally injected corticosteroids.
• Lymphosarcoma (LSA) in the eyelid often represents spread (metastatic disease) of the cancer from somewhere else in the body. In early stages of eyelid/conjunctival LSA, chemotherapy may reduce the size of the tumor and result in remission in some animals. However, response to chemotherapy is unpredictable and dependent on numerous factors.
• Response to medical therapy for all other eyelid tumors is poor. This is in contrast to some forms of inflammation of the eyelids, which often respond well to various medications.

Surgical Management

• The recommended treatment for many eyelid tumors in the cat is surgical removal. This can be often be accomplished by removing a portion of the eyelid along with the tumor and then suturing the remaining eyelid back together. The tissue is then submitted for biopsy examination.
• Complete excision of some eyelid tumors in the cat is curative. Some eyelid tumors invade nearby tissue microscopically and may recur following surgery. Other new tumors may also develop in the same or opposite eye. These new tumors typically do not represent spread of disease, but rather spontaneous development of new lesions.
• Extensive plastic and reconstructive surgery may be necessary following the removal of very large tumors. Maintaining a continuous eyelid margin and mobile upper eyelid are paramount to maintaining eye health and vision. As a general guideline, eyelid margin tumors that involve greater than 1/3 of the total length of either the upper or lower eyelid prevent simple removal of the tumor, and necessitate performing reconstructive surgeries. It is not uncommon for major reconstructive surgeries that involve the skin of the face and neck to be undertaken in stages; often with at least two separate surgeries.
• Certain types of tumors may respond to cryotherapy, which is freezing of the tumor. This therapy may be considered for some small mast cell tumors, small and confined squamous cell carcinomas, and selected other tumors.
• Some eyelid tumors are too large or extensive to remove surgically, and enucleation or removal of the eye is necessary. Advanced eyelid tumors may extend into the soft tissues behind the eye (into the orbit) or into the eye.

Home Care for the Cat with Eyelid Tumors

Optimal treatment for your cat requires a combination of home and professional veterinary care. Most cats are sent home wearing an Elizabethan collar to prevent self-trauma to the surgery site. Follow-up visits are important, especially if recurrence of the eyelid tumors is a possibility. Administer all prescribed medication as directed. Alert your veterinarian if you are experiencing problems treating your pet. If any signs of squinting or yellow-green infected discharge occur following the surgery, notify your veterinarian. Sutures are usually removed in 10-12 days after the surgery.

The risk of recurrence or re-growth of eyelid tumors after surgical removal is high for some eyelid tumors of cats. Malignant tumors have a higher risk of recurrence than do benign eyelid tumors. Early diagnosis and prompt treatment result in the best outcome. The chance of recurrence depends upon the type of tumor, whether or not chemotherapy effectively caused decrease in size of the tumor, the stage of tumor development at the time of surgery, and whether or not the entire tumor could be surgically removed.