case_images: PMC10996350_01
case_images: Biopsy slides show a polypoid mass lined by benign squamous mucosa with underlying extensive proliferation of plasma cells. The plasma cells are mostly mature in appearance, but some plasma cells are mildly enlarged, and occasional plasma cells show plasmablastic morphology. Mitotic activities are present, but not risk.
case_images: 10.1177_23247096241242237-fig1.jpg
case_images: PMC10996350_01_10.1177_23247096241242237-fig1.jpg
case_images: fig1-23247096241242237
case_images: Surgical pathology of the right lateral pharyngeal wall lesion revealed a plasmacytic neoplasm favoring an EMP (Figure 1).
case_images: Immunostains demonstrated CD138 positivity (A), highlighting plasma cells. On in situ hybridization, the plasma cells were monotypic for immunoglobulin light chains kappa (B) and negative for lambda (C).
case_images: 10.1177_23247096241242237-fig2.jpg
case_images: PMC10996350_01_10.1177_23247096241242237-fig2.jpg
case_images: fig2-23247096241242237
case_images: On immunostaining, the tumor cells were positive for CD 138, MUM-1, CD 79a, and CD117 (Figure 2). On in situ hybridization, the plasma cells were monotypic for immunoglobulin (IgA) light chains kappa and negative for lambda (Figure 2).