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.

Clinical Outcomes of Proton Beam Therapy for Choroidal Melanoma at a Single Institute in Korea.

PURPOSE: This study retrospectively evaluated the clinical outcomes and complications of proton beam therapy (PBT) in a single institution in Korea and quantitatively analyzed the change in tumor volume after PBT using magnetic resonance imaging (MRI). MATERIALS AND METHODS: Twenty-four treatment-naïve patients who underwent PBT for choroidal melanoma between 2009 and 2015 were reviewed. Dose fractionation was 60-70 cobalt gray equivalents over 5 fractions. Orbital MRIs were taken at baseline and 3, 6, and 12 months after PBT and annually thereafter. The tumor volume was reconstructed and evaluated by stacking the tumor boundary in each thin-sliced axial T1-weighted image using MIM software. RESULTS: The median follow-up duration was 36.5 months (range, 9 to 82 months). One patient had suspicious local progression and two patients had distant metastasis. The 3-year local progression-free survival, distant metastasis-free survival, and overall survival rates were 95.8%, 95.8%, and 100%,respectively. Five Common Terminology Criteria for Adverse Event ver. 4.03 grade 3-4 toxicities were observed in four patients (16.7%), including one with neovascular glaucoma. The mean tumor volume at the baseline MRI was 0.565±0.084 mL (range, 0.074 to 1.610 mL), and the ratios of the mean volume at 3, 6, and 12 months to that at baseline were 81.8%, 67.3%, and 60.4%, respectively. CONCLUSION: The local controlrate and complication profile after PBT in patientswith choroidal melanoma in Korea were comparable with those reported in a previous PBT series. The change in tumor volume after PBT exhibited a gradual regression pattern on MRI.