User:Dr meetsingh/Orbital lymphoma

Introduction
It is common type of non-Hodgkin lymphoma. It can be intra ocular and adnexal. Common clinical presentation are decreased vision and nonresolving uveitis. Diagnosis is mostly based on the intraocular biopsy specimen. Treatment is mainly by chemoradiation.

Ocular lymphoma represents 55% of all cases of lymphoma in adults and 10% cases in older patients

Proptosis and visible conjunctival mass are the common modes of presentation. It occurs in latter part of life and symptoms are due to increase mass effect. Both occular and adnexial lymphoma have shown association with systemic lymphoma in 30-35% of cases. Prognosis is mainly by histologic type and stage as wwell as treatment that is applied. Survival rate is overall approximately 60% in 5 years

Pathophysiology

 * Recent studies have demonstrated that presence of viral DNA in ocular lymphoma cells thus confirming role of infectious agents in pathogenesis


 * Follicular lymphoma, diffuse large B cell lymphoma, mantle cell lymphoma,B-cell chronic lymphocytic leukemia, peripheral T-cell lymphoma, and natural killer cell lymphoma have also been reported to affect the orbit.


 * The aging population, the increasing number of immunosuppressive drugs, and the AIDS epidemic have also contributed to the increased incidence of NHL.


 * Chlamydia psittaci is associated with ocular adnexal mucosa-associated lymphoid tissue (MALT) lymphoma and association varies across geographical areas. In South Florida, orbital and adnexal lymphomas are not associated with C psittaci infections.

Epidemiology

 * The National Cancer Institute Surveillance in 2008, 2,390 US men and women (1,340 men and 1,050 women) would be diagnosed with eye cancer and 240 people would die of this disease


 * Studies have shown increase lifetime risk and incidence of this orbital NHL


 * More prevelant in Asians(Korea and Japan) and Europe


 * Intraocular lymphoma is rare but over the decades incidence is rising particularly in immunocompromised patients and immunocompetent patients


 * Increase incidence is also due to advancing age affects elderly people at seventh decade of life.


 * No sex predilection was noted for ocular lymphomas in some studies. However in cases of intraocular lymphoma women are more affected than man and in some studies orbital lymphoma was found to have a female preponderance

Clinical Presentation
Symptoms are different according to whether it is intraocular or adnexal and orbital

Intraocular lymphoma
Mainly two types 1.Primary central nervous system involvement(PCNSL)

2.Primary central nervous system with ocular involvement(PCNSLO)

On clinical presentation PCNSLO may be either unilateral or bilateral but mostly cases present as bilateral involvement. Intracranial disease occurs in 56-85% of patients with ocular disease, and estimates suggest that 15-25% of patients who present with CNS disease have ocular disease—hence the distinction between PCNSL and PCNSLO. Subjective symptoms include painless decreased vision, photophobia, red eye, and floaters. In some patient with known disease of PCNSL may be detected by routine examination. Diagnosis is difficult because due to its insidious onset and simulate other diseases.

In PCNSLO is common in person who are severely immunosuppressed. Metastatic systemic lymphoma, like other metastatic ocular tumors, is usually confined to the uvea—in particular, the choroid. Compared with PCNSLO, metastatic systemic lymphomas are much less prevalent, have a better prognosis, and are less likely to create a diagnostic dilemma