Fig. 5

a The nasopharyngeal posterior wall was uplifted under the WL mode. The left pharyngeal recess was full. The nodular neoplasm was observed. b The posterior wall was uplifted due to the thickened mucosa. Proliferous lymphoid tissues were observed under the mucosa (white arrow). c The neoplasm parenchyma in the left pharyngeal recess refers to proliferous lymphoid tissues (blue arrow). The nasopharyngeal tissue was submitted for pathological examination on the position guided by the arrow, with a definite diagnosis of chronic inflammation of the nasopharyngeal mucosa