01 April 2026
: Case report 
A 64-Year-Old Man Presenting With Diplopia and Right Orbital Swelling Due to Mucosa-Associated Lymphoid Tissue Lymphoma
Challenging differential diagnosis, Rare disease
Lubna M. Altamimi ABDEF 1, Farjah H. Algahtani
ABDEF 1,2*, Mohammed Ghannam Alharbi ABD 1,2,3, Fadi S. Alakeel ABE 1,4, Beshayer A. Alhentti ABD 1,4
DOI: 10.12659/AJCR.951426
Am J Case Rep 2026; 27:e951426
Figure 4 Immunohistochemical profile demonstrating B-cell lineage and anti-apoptotic marker expression. (A) Strong, diffuse membranous positivity for CD20, confirming B-cell phenotype (×200). (B) CD43 shows weak and patchy membranous staining in a subset of tumor cells (×200). (C) Tumor cells show diffuse cytoplasmic positivity for BCL-2, indicating extranodal marginal-zone lymphoma of MALT type. MALT – mucosa-associated lymphoid tissue.