patient presenting with conjunctival lymphoma must be referred to an oncologist for a systemic workup.
The treatment of conjunctival lymphoma depends on the presence or absence of systemic involvement. When disease is localized to the conjunctiva, the mainstay of treatment is orbital radiation; in cases with systemic involvement, the treatment is chemotherapy. See Chapter 8 in BCSC Section 8, External Disease and Cornea, and Section 7, Orbit, Eyelids, and Lacrimal System, for additional discussion. Interestingly, some case series have provided evidence of an infectious trigger (Chlamydia psittaci) for conjunctival lymphoma, for example, by demonstrating chlamydial DNA in a high proportion of cases of marginal zone lymphoma. Less common microbial associations with conjunctival/orbital lymphoma include Chlamydia pneumoniae, Chlamydia trachomatis, and
Helicobacter pylori, the latter being more commonly associated with gastric lymphoma. Accordingly, cases of regression have been reported with oral doxycycline treatment. Viruses such as hepatitis C and Epstein-Barr have also been implicated in lymphoproliferative disorders.
The overall prognosis in conjunctival lymphoma is good, given that most cases are low-grade neoplasms. However, the prognosis in any given case depends on the subtype of lymphoma, because this has bearing on the likelihood of systemic disease. In the absence of systemic involvement, the remission rate at 10 years is 75%–100% for patients treated with radiation therapy; with systemic involvement, disease-free survival at 5 years is only 20%. Lymphoma-related death is significantly associated with advanced clinical stage and age older than 60 years. The extent of p53 positivity (tumor suppressor gene) and MIB-1 positivity (cell proliferation marker) has also been shown to affect prognosis, although these stains are not routinely obtained in all cases. The average time frame for relapse of marginal zone lymphoma is more than 5 years after initial remission. Thus, these patients require long-term (over 5 years) follow-up.
See the appendix for the AJCC staging.
Shields CL, Shields JA, Carvalho C, Rundle P, Smith AF. Conjunctival lymphoid tumors: clinical analysis of 117 cases and relationship to systemic lymphoma. Ophthalmology. 2001;108(5):979–984.
Swerdlow SH, Campo E, Harris NL, et al. WHO Classification of Tumours of Haematopoietic and Lymphoid Tissues. 4th ed. Lyon, France: IARC; 2008.
Glandular Lesions
Figure 5-26 Oncocytoma. A, Clinical appearance at the caruncle. B, Histology shows proliferation of glandular epithelial cells, with deeply eosinophilic cytoplasm. Some of the cells surround protein-filled lumina (arrows). (Part A courtesy of Mark J.
Mannis, MD; part B courtesy of George J. Harocopos, MD.)
Oncocytoma is a benign proliferation of apocrine or accessory lacrimal gland epithelium, that is, an adenoma. It typically arises in the caruncle, although it may occasionally be seen elsewhere on the conjunctiva. Oncocytoma most commonly occurs in elderly women. Clinically, it appears as a tan to reddish, vascularized nodule (Fig 5-26). When this lesion is seen clinically, the differential diagnosis typically includes squamous, melanocytic, and lymphocytic lesions, as well as amyloid. Histologically, the lesion is composed of proliferating epithelial cells, similar in appearance to apocrine (gland of Moll) epithelium, around glandlike spaces. Because of the cystic appearance of these spaces, the term apocrine cystadenoma is also used to describe this lesion. The epithelial cells exhibit distinctive eosinophilic cytoplasm; hence, this lesion is also referred to as oxyphilic (eosinophilic) cystadenoma. Malignant apocrine neoplasms may also occur but are very rare.
Other Neoplasms
Virtually any neoplasm that can occur in the orbit may occasionally arise in the conjunctiva, including neural, muscular, vascular, and fibrous tumors. Metastatic lesions to the conjunctiva are rare but may occur. See Chapter 14 of this volume. See also BCSC Section 8, External Disease and Cornea, and Section 7, Orbit, Eyelids, and Lacrimal System.