Patterns of care for orbital marginal zone B-cell lymphoma of mucosa-associated lymphoid tissue in Korea throughout 2016: Results from a multicenter cross-sectional cohort study (KROG 16–19)

Aim: Primary orbital mucosa-associated lymphoid tissue (MALT) lymphomas are generally sensitive to radiotherapy (RT), but a “wait and see” strategy has also been used in asymptomatic patients. Recently, orbital MALT lymphoma has been reported to be associated with Chlamydia psittaci infection. This study aimed to assess the current patterns of care in clinical practice for orbital MALT lymphoma in South Korea. Methods: We performed a multicenter, cross-sectional cohort study of patterns of care for orbital MALT lymphoma in South Korea throughout 2016. All patients were pathologically confirmed to have orbital MALT lymphoma. Results: Overall, eight institutions with 90 patients participated. The survey showed that the most frequent upfront treatment for orbital MALT lymphoma was RT (80/90, 90%). Other treatment modalities were given to a limited number of orbital MALT lymphoma patients as follows: watch and wait, 6/90 (7%); antibiotics, 3/90 (3%) and chemotherapy, 1/90 (1%). Generally, RT was administered to the entire involved site such as the entire conjunctiva/eyelid or entire orbit (96%), with a median total dose of 25.2 Gy. Lens shielding was performed for most patients with conjunctival and eyelid tumors (93%). Conclusions: RT was the conventional treatment modality for orbital MALT lymphoma. Currently, RT is performed for the entire involved subsites at a lower dose than that previously used, and lens shielding was applied to minimize the orbital complication.