Abstract
Purpose: :
highlight the interest of biopsy and positron emission tomography (PET scan) in diagnosis of orbital Malt Lymphoma (ML)
Methods: :
clinical cases.We report 3 cases illustrating the diversity of the orbital localization in ML. Case 1 is a 41 year old woman presenting an unilateral corticosteroid resistant dacryoadenitis. The PET scan fixes clearly at the orbit. After anatomopathologic confirmation, an orbital radiotherapy is carried out and leads to the clinical and tomographic remission. Case 2 is a 61 year old patient presenting a small cell carcinoma of the lung, initially refered for unilateral exophthalmy. RMI highlights a bilateral orbital infiltration, with hot spot in PET scan. The clinical suspicion of orbital metastasis is not confirmed : biopsy concludes ML. Case 3 is a 64 year old woman refered for an unilateral and resistant conjunctival hyperhemia. Clinical diagnosis is in fact a myositis of the superior right muscle. The PET scan does not fix in orbit but reveals a pleural localization. The muscular biopsy concludes once more ML.
Results: :
If the lacrymal gland localization is well known, orbital infiltration and orbital myositis are less common, and highlight the interest of a non invasive exploration before biopsy. The diagnosis of an orbital localization in ML imposes general assessment in order to eliminate extraocular localizations. The slowness of evolution as its corticosteroid resistance must lead to suspect ML and carry out a biopsy. Publications about orbital ML are few and report small series, because of the low frequency of this pathology. Interest of TEP scan in orbital ML is not well reported. In our experience, it was useful in the 3 cases. It fixed in 2 cases in orbit (dacryoadenitis, orbital infiltration), in the third case (myositis) TEP scan revealed an extraocular localization and was decisive for treatment.
Conclusions: :
Orbital ML can take different masks that are sometimes disconcerting. TEP scan is very useful in diagnosis before the biopsy, in therapeutic decision and in follow-up after treatment even if it does not always fix in orbit.
Keywords: imaging/image analysis: non-clinical • oncology • pathology: human