Eye, Orbit, and Adnexal Structures
Summary of Key Points
Incidence
• Primary ocular (eye) and ophthalmic (eye and adnexa) tumors are relatively uncommon.
• The most common primary ocular tumors are choroidal melanoma and retinoblastoma. The most common adnexal tumors are lymphoma, rhabdomyosarcoma, optic nerve glioma, and epithelial and melanocytic malignancies of the eyelid and conjunctiva, respectively.
• Many systemic neoplasms can involve the eye and adnexa, especially breast and lung cancers, as well as lymphoma and leukemia.
Etiology
• The etiology of most ophthalmic tumors is unknown.
• Retinoblastoma is the prototypical model of a genetically transmissible tumor via loss of a tumor suppressor gene.
• Squamous neoplasms of the eyelids and conjunctiva are associated with sun exposure, immunosuppressed states, and viral infections such as human papillomavirus and human immunodeficiency virus.
• Ocular and orbital metastases are frequently unexpected; approximately 25% of ocular metastases are discovered at an occult stage.
Diagnosis
• Intraocular tumors can be directly visualized, greatly facilitating diagnosis, but performing a biopsy is not easy and is limited to special circumstances.
• For intraocular tumors, a combination of funduscopic examination, intravenous angiogram, ultrasonography, and computed tomography/magnetic resonance imaging (CT/MRI) can yield diagnostic accuracies greater than 90% to 95%.
• Orbital and adnexal tumors are diagnosed by CT/MRI imaging and biopsy.
Treatment
• Intraocular tumors are treated with local modalities such as external beam irradiation, brachytherapy, and photocoagulation, with or without chemotherapy. If useful vision cannot be preserved in the eye affected by a tumor, the eye is enucleated.
• Orbital malignancies are frequently treated by excision and radiation/chemotherapy, but exenteration may be necessary in far-advanced sarcomas.
• Eyelid, conjunctival, and corneal malignancies are managed by local excision, with or without topical chemotherapy, cryotherapy, or irradiation.
• Metastatic malignancies may be palliated by external beam irradiation and adjuvant chemotherapy.
• Because radiation is widely used in treatment of ophthalmic malignancies, radiation toxicity is an exceedingly important issue in management protocols. Ophthalmic tissue components range from extremely radiosensitive tissues, such as the lens, to relatively radioresistant tissues, such as the retina and the optic nerve.
1. Which statement (s) is correct regarding primary intraocular lymphoma (PIOL)?
A PIOL is a rare subset of intraocular primary central nervous system (CNS) lymphoma (PCNSL) in which the disease invades the eye but at the time of ocular diagnosis, CNS involvement may or may not be present.
B A great majority of PCNSLs are of large B-cell histology.
C PIOL is a common neoplastic masquerade syndrome involving the eye; most patients present with uveitis-like symptoms including pain, blurred vision, and vitritis.
D Treatment of PIOL may include external beam radiation therapy (EBRT) and systemic chemotherapy.
2. Which statement(s) is/are correct regarding intraocular uveal melanoma?
A A great majority (more than 98%) of these tumors are seen in the Caucasian race.
B Most patients remain asymptomatic unless the uveal melanoma involves the macula.
C These tumors occasionally may be amelanotic (almost white in color).
D Indirect ophthalmoscopy and ultrasonography are the most important diagnostic modalities in the evaluation for suspected choroidal melanoma.
3. Which option(s) is/are correct for retinoblastoma?
A Retinoblastoma is the most common intraocular neoplasm of childhood.
B Approximately 300 new cases are diagnosed annually in the United States.
C Approximately one third of retinoblastoma cases have bilateral tumors, and all are considered hereditary.
D Ninety-five percent of retinoblastoma cases are diagnosed with indirect ophthalmoscopy and ocular A- and B-scan ultrasonography.
4. Which options(s) is/are correct for conjunctival/eyelid Kaposi sarcoma?
A Kaposi sarcoma is a multifocal disease.
B In some instances the Kaposi sarcoma may present as the initial sign of acquired immunodeficiency syndrome.
C Conjunctival tumors appear as flat or slightly elevated, dark reddish plaques or as larger, circumscribed nodules.
D With normalized CD4+ levels, the associated Kaposi sarcoma may regress.
5. Which option(s) is/are correct for sebaceous gland carcinoma?
A Sebaceous gland carcinoma is a relatively rare eyelid adenocarcinoma that originates from the meibomian and/or Zeis glands.
B Sebaceous gland carcinoma accounts for approximately 5% of all malignant eyelid tumors.
C Sebaceous gland carcinoma has a predilection for elderly women.
D Sebaceous gland carcinoma is seen more often in the upper eyelid than in the lower eyelid.
6. Which option(s) is/are correct for lacrimal gland tumors?
A Primary neoplasms of the lacrimal gland include lymphoproliferative tumors and the epithelial lesions originating from the ductal and acinar epithelium of the gland.
B The lymphomas and pseudotumors of the lacrimal gland are two to three times more common than the epithelial neoplasms of the lacrimal fossa.
C Adenoid cystic carcinoma accounts for approximately half of the epithelial malignancies in the lacrimal fossa and causes perineural invasion of the peripheral nerves, accounting for the symptoms of pain and numbness.
D Lacrimal gland carcinomas typically manifest with upper eyelid fullness and rapidly developing downward and medial displacement of the globe with diplopia.
