Mr. Liu, 36 years old, found swelling in his right eye in October 2012 without any abnormal sensation, and later found that the swelling could not subside, so he went to the hospital for examination and was thought to have conjunctivitis. What kind of disease is mucosa-associated lymphoma? Mucosa-associated lymph-phoid tissue (MALT) lymphoma is a low-malignancy B-cell lymphoma. Like other lymphomas, MALT lymphoma can become highly malignant and can invade sites outside of the lymph nodes in addition to the lymph nodes. Ocular appendage MALT lymphoma (OAML) is one of the more common types of orbital malignant lymphoma, which can infiltrate the orbit and other ocular appendages, with an average age of 65 years. What are the main manifestations of MALT lymphoma of the ocular appendages? Lymphoma arising in the orbit is characterized by swelling of the eyelid, protrusion of the eyeball, limitation of eye movement, and loss of vision. The direction of eye protrusion correlates with the location of the orbital tumor; the muscles with restricted eye movement correlate with those affected by tumor infiltration. The masses may occur in one or both eyes. Lymphomas arising in the conjunctiva complain of ocular redness, foreign body sensation, and ptosis. Physical examination reveals a dark red soft tissue mass under the lid conjunctiva, fornix conjunctiva, or bulbar conjunctiva, or a pink thickening of the conjunctival surface with a smooth, fish-like surface and clear boundaries with the surrounding tissue. The conjunctiva is mildly to moderately congested. What tests are needed to detect ocular swelling and prominence? Imaging tests such as CT, MRI and ultrasound of the orbit are required. Ultrasound of the eye mostly shows irregular masses with clear borders, uneven internal echogenicity, mostly hypoechoic, and unremarkable acoustic attenuation. Orbital CT mostly showed diffuse soft tissue hyperplasia without envelope and unclear borders. When the tumor tissue fills the whole orbit, it has a typical “casting-like” appearance. On orbital MRI, the tumor is mostly equivocal or low signal on T1WI and equivocal or high signal on T2WI, which is more uniform. How to treat MALT lymphoma of the ocular appendage after detection? MALT lymphoma of the ocular appendage is a painless malignant tumor with a low lethality rate; therefore, for some patients, observation only is sufficient. Some lymphomas often affect the patient’s quality of life and therefore require prompt treatment, which consists mainly of surgical resection and post-operative radiation therapy and chemotherapy. Can surgical treatment be completely removed? Surgery is the primary treatment for MALT lymphoma of the ocular appendages. The importance of surgery is that it is a necessary step in establishing the diagnosis; in some patients it is part of the treatment pathway, with complete resection of the lacrimal gland, conjunctiva, and anterior orbital lesions; deep orbital, extraocular muscle, and peri-optic nerve lesions do not require complete resection, primarily on the basis of reducing complications and not affecting survival. Partial resection and complete resection have been shown to have similar outcomes in stage I patients. What is the need for radiation therapy? Radiation therapy is also an important measure in the treatment of OAML. If the conjunctiva is largely resected, radiotherapy can be withheld. This is because it is not too late to re-treat with radiation even if there is a recurrence. Are there any side effects of radiotherapy? What do I need to pay attention to during radiotherapy? Radiation therapy definitely has a good effect and is relatively safe. The dose of 3600 rads is usually sufficient, which does not damage the lens and optic nerve, but the radiation therapy equipment and the experience of the radiation therapist are very important, as some may make the complications very serious, and some are inexperienced in the wrong direction. Bring orbital imaging data and pathology reports to the clinic, preferably to a specialized hospital with extensive experience in ocular radiotherapy. Radiotherapy can be given after localization, about 20 days, and can be done without hospitalization. Prognosis of MALT lymphoma of the ocular appendages? 84-100% of patients are in stage I, an inert clinical course with a long disease-free period and a relatively good prognosis.