fig2

Figure 2. Variability of growth patterns in type A thymoma: (A) fascicular growth pattern characterized by elongated fascicle of bland spindle cells, occasional storiform pattern, and sometimes whorling of tumor cells is a common feature of these tumors (20×); (B) Hemangiopericytic growth pattern characterized by numerous branching vessels with open lumina is another appearance Type A thymoma can adopt (20×).