November 2009

 

OPHTHALMOLOGY NEWS

 

Symptoms, treatment for eye lesions


by David Laber EyeWorld Staff Writer

   

At the ASCRS Winter Update earlier this year, attendees received thorough coverage of benign and malignant conjunctival tumors including appearances, treatment options and potential pitfalls

Conjunctival tumors can be deadly to a patient, and with some malignant lesions mimicking benign tumors, physicians need to know what to look for.

At the 2009 ASCRS Winter Update earlier this year in the Rivera Maya, Mexico, Helen K. Wu, M.D., Tufts University School of Medicine, Boston, detailed many of the types of conjunctival lesions and tumors while providing pearls for diagnosing and treating the patient.

Recognizing the benign

Benign lesions have several characteristics that differentiate them from malignant lesions, Dr. Wu said. Some types of benign lesions include squamous papilloma, keratoacanthoma, hereditary benign intraepithelial dyskeratosis, keratotic plaque, actinic keratosis, pterygium and pingueculum.

The most common benign neoplasm of conjunctiva is squamous papilloma, which is associated with human papillomavirus (HPV). It is marked by a pink, fibrovascular frond of the tissue, either sessile or pedunculated. Its pathology shows finger-like projections of fibrovascular tissue, usually acanthotic, with hyperkeratosis. It can be treated with surgical excision, cryotherapy or topical chemotherapy.

Keratoacanthoma lesions are inflammatory lesions that might mimic carcinoma, Dr. Wu said. They are raised, fleshy, oftentimes nodular lesions; though sometimes they are gelatinous or leukoplakic that onset rapidly. Pathologically, they are brought on by hyperkeratosis and acanthosis with neutrophilic infiltrate and microabscesses. They should be treated with excision.

Keratotic plaque appears as a white conjunctival mass with keratinized, acanthotic epithelium. It appears similar to squamous cell carcinoma with leukoplakia, she said.

Actinic keratosis appears as a frothy white lesion often located over a pingueculum or pterygium. It shows dysplastic, keratotic epithelium and also can resemble squamous cell carcinoma.

Dr. Wu said hereditary benign intraepithelial dyskeratosis is seen primarily in some Native American tribes. It is autosomal dominant disorder with elevated fleshy plagues and shows acanthosis, dyskeratosis and inflammatory cells.

Malignant lesions—SCC Malignant lesions come in the form of conjunctival invasive squamous cell carcinoma (SCC), sebaceous cell carcinoma and conjunctival melanoma, Dr. Wu said.

Pre-invasive types of squamous cell carcinoma include conjunctival intraepithelial neoplasia (CIN), which is marked by a mild or severe dysplasia depending on the thickness of the abnormal cell proliferation, and carcinoma in situ (CIS), which is characterized by full thickness of the epithelium with abnormal cells. As for invasive squamous cell carcinoma, it invades the stroma and might metasize.

“CIN is the most common conjunctival malignancy in the United States, and it is usually seen in older men,” Dr. Wu said. Typically, it is found in intrapalpebral fissure or at the limbus. CIN is associated with ultra violet light exposure, fair pigmentation, HPV infections and, in younger patients, HIV. It is a precursor to squamous cell carcinoma, and it partially involves the epithelium without invading the basement membranes.

Physicians can diagnosis CIN with a conjunctival biopsy. Treating CIN involves a wide excision with adjunctive cryotherapy. The recurrence rate after excision ranges from 5 to 50% depending on the excised margins. Mitomycin C (MMC) and interferon (IFN)-alpha 2b drops or injection may be used in conjunction with surgery. Intraocular or orbital invasion are rare.

People at risk of developing CIN are older men who are exposed to more sunlight, smoke, have a lighter complexion and/or have HPV, HIV or AIDS. It is located in the interpalpebral zone, is larger in size with prominent vessels, spontaneously hemorrhages and strongly adheres to the globe posteriorly to the limbus suggestive of malignancy.

Pigmented SCC can mimic conjunctival melanoma, Dr. Wu said. The risk of metastasis from SCC is less than 1% in 10 years as compared to the 26% risk associated with melanoma.

It is treated by surgical excision with cryotherapy (with a recurrence rate of 10-20%). It is a no-touch technique involving a partial lamellar sclerectomy and keratectomy. Dr. Wu said she applies absolute alcohol to the sclera bed as well. Topical chemotherapy has better results on smaller, thinner tumors, and it may be used as an adjunctive therapy to shrink the tumor before excision. Radiation also is a treatment option.

There are side effects associated with surgical excision, however. For example, it is difficult to obtain clear margins; so surgical excision might leave subclinical microscopic tumor cells behind resulting in a relatively high recurrence rate.

Also, extensive scarring might result after a wide excision with the potential for diplopia, symbepharon formation and/or dryness. The limbal stem cells might be damaged with the conjunctivalization of the cornea. And finally, the patient might develop intraocular inflammation, corneal edema or fibrosis, and iris atrophy from cryotx.

For topical chemotherapy, the MMC may cause stromal necrosis, corneal toxicity and ulceration, punctal stenosis, uveiti, and cutaneous erythema and edema. Alpha-interferon, an alternative that can be given as an injection subconjunctivally, is less toxic than MMC, but it might require prolonged therapy and is expensive.

Radiation, which plays a limited role in the management of squamous neoplasms, requires high doses of plaque radiotherapy because CIN is relatively resistant to radiation. The plaque must cover the entire span of the tumor, which makes it difficult to use on diffuse tumors, but it also makes it more useful for reoccurring tumors. Potential side effects include scleral necrosis and cataract formation.

Malignant lesions - sebaceous cell carcinoma

Sebaceous cell carcinoma is most commonly found in the periocular area in the meibomian and Zeis glands, and it is most common on the upper lid, Dr. Wu said. Its mortality rate is 22%, and it is most common in women in their 70s as well as Asians, Indians and American Caucasians. It might be seen in younger patients with a history of radiation to the face.

“Sebaceous cell carcinoma might falsely present as chronic blepharitis or chalazion,” she said. “It also could mimic unilateral blepharoconjunctivitis, basal or squamous cell CA, conjunctival or corneal CIN, SLK or orbital inflammations.” It is a firm, painless mass and could cause the loss of the patient’s eyelashes.

Sebaceous cell carcinoma is characterized a pagetoid spread similar to Paget’s disease, and foamy cytoplasm should be present as well as positive fat stains. It might be multicentric with numerous sebaceous elements and mitiotic figures and nests with central necrosis. Aggressive local control and sentinel nod biopsy are recommended as the tumor invades locally, and some physicians prefer exenteration if it diffuses.

Editors’ note: Dr. Wu has no financial interests related to her comments.

Contact information

Wu: 617-636-5784, helenkw@aol.com

Eye lesions: Symptoms and treatment Eye lesions: Symptoms and treatment
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