NAVLE（北美执业兽医考题）Day 614

A five-year-old boxer is presented for routine vaccinations. The owner points out a small, smooth mass on the right ear. Fine needle aspiration cytology is shown below. Which one of the following choices is the most likely diagnosis？

一只5岁的拳狮犬来做常规疫苗，主人指出它的右耳处有一个小而光滑的肿块。其细针抽吸的细胞学结果如下图。以下哪个选项是最可能的诊断？