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Paper text:
non - hodgkin s lymphomas are neoplastic diseases of the lymphatic system , usually involving the lymph nodes , but almost 2540% of the cases have extranodal onset .
orbital lymphomas represent about 2% of all lymphomas , 5- 15% of extranodal lymphomas and approximately 50% of all primary malignant tumors of the orbit .
an association between chlamydia psittaci infection and orbital adnexal lymphoma has been described , and also , thyroid eye disease is considered to be a predisposing factor .
clinical signs and symptoms are nonspecific , often delaying the diagnosis . in 25% of the cases the conjunctiva is involved and the patients present with salmon red patches or swollen conjunctiva . in the rest of the patients , presentation is with orbital mass .
common signs at presentation are : palpable mass , pain , exophtalmia , ptosis , dyplopia , decreased vision and abnormal ocular movement . in approximately 1017% of cases
the lymphoma appears bilaterally , simultaneously in both orbits in 80% of cases and subsequently in 20% of cases .
between 2040% of the patients have extraorbital lymphoma at onset , especially those with aggressive histology .
the majority of orbital lymphomas are of low - grade histology ( 84% ) , the minority ( 16% ) being aggressive lymphomas .
other histological types are : follicular , lymphocytic , mantle cell and diffuse large b - cell lymphomas .
diagnosis is based on biopsy and staging procedures should include imaging investigations : computed tomography ( ct ) , or magnetic resonance imaging ( mri ) to evaluate local extension but also systemic lymphomatous involvement .
differential diagnosis should include other malignant tumors and inflammatory pseudo - tumors of the orbit and thyroid associated orbit disease .
the prognosis of ocular lymphoma depends on the histological type , age , localization and stage of disease .
favorable prognostic factors are : low - grade histology , younger age , conjunctival localization and early stage at presentation .
treatment depends on the stage : in localized orbital lymphoma , radiotherapy is highly effective , while in patients with high grade histology or disseminated lymphoma , systemic chemotherapy should be used . in some localized cases , antibiotic therapy against chlamydia results in complete remission .
a case of bilateral orbital lymphoma is presented below , having the approval of the ethical committee of the hospital and the written consent of the patient for publishing his pictures .
a 50 years old male patient referred first to the ophtalmology clinic in april 2012 for bilateral exophtalmos and palpebral ptosis .
biopsy was refused by the patient . in november 2012 , he was admitted at the maxillofacial surgery clinic for bleeding from the periorbital tumors .
a biopsy was performed and diffuse large b - cell lymphoma was diagnosed . on admission to the hematology clinic the patient presented bilateral periorbital tumors ( 12 cm in the right and 8 cm in the left side ) , involving the eyelids and incorporating the eye globes ( fig . 1 and 2 ) .
the patient also complained of complete loss of vision and constitutional symptoms ( night sweats and weight loss ) .
laboratory tests revealed leucocytosis ( 13000/microliter ) with 55% atypical lymphocytes in the peripheral blood smear , anemia ( hemoglobin=10g / dl ) , elevated erythrocyte sedimentation rate and decreased level of igg and iga .
serological tests for chlamydia , hiv and hepatitis viruses ( b and c ) were negative .
cranio - orbital ct revealed bilateral orbital tumors ( 14/8/11 cm in the right with 2.7 cm ptosis of the right eye and 7.8/5.6/6.5 cm in the left with 2 cm ptosis of the left eye ) , without invasion of the eye globes , bones , paranasal sinuses or of the cerebral parenchyma ( fig . 3 and 4 ) .
cervical and thoraco - abdominal ct showed enlarged latero - cervical and retroperitoneal lymph nodes .
the patient was diagnosed with stage ivb diffuse large b - cell primary orbital lymphoma and r - chop ( rituximab + cyclophosphamide , adriblastin , vincristin and prednison ) chemotherapy was started , which produced a rapid response .
r - ice ( rituximab + iphosphamide , carboplatin and etoposide ) second - line chemotherapy was started and complete remission was obtained after 4 cycles ( fig . 5 ) .
he did not return for completion of the chemotherapy cycles , nor for follow - up .
primary orbital lymphoma is a rare disease , diagnosis being difficult due to nonspecific symptoms at presentation .
patients usually present with unilateral orbital tumors , only 1017% of the cases having bilateral orbital involvement at onset .
ocular lymphomas have low - grade histology in the majority of the cases and prognosis is good if diagnosis is made in early stages .
however , permanent loss of vision can be seen due to optical nerve atrophy , even in patients with a complete remission of the lymphoma .
treatment consists of radiotherapy in localized disease but if systemic involvement is present , chemotherapy should be used .
the particularity of this case is the presence of massive orbital tumors , due to delayed diagnosis .
long - term prognosis of this patient is unfavorable , due to the advanced stage of the disease at presentation and early relapse after an initial good response to chemotherapy .
extranodal onset can be seen in approximately 2540% of the cases of non- hodgkin lymphomas and diagnosis is often difficult due to nonspecific symptoms . 
 orbital lymphomas represent approximately 50% of the orbital malignancies . 
 common symptoms and signs at presentation are : palpable tumor , exophtalmia , dyplopia and decreased vision . 
 diagnosis can be made only by biopsy and early treatment is important in order to increase the chance of cure . 
 we present the case of a patient whose diagnosis and treatment were delayed due to refusal of biopsy and , although complete remission of lymphoma was obtained , the vision loss was permanent because of prolonged compression on the optic nerves . 
 a particularity of this case is the presence of massive periorbital tumors on admission to the hospital , incorporating the eye globes completely and causing impressive facial deformity .