Histologically, the tumors were characterized by widespread myxoid, cyst formation, vessel wall hyalinization, and absence of mitoses.

组，病变具有广泛的粘液样变、囊腔形成、血管壁透明变性和缺核分裂相等特点。

Figure 2.B, On high-power magnification microscopy, the specimen showed a patternless tissue culture-like appearance with multiple mitoses and extraasated red blood cells.

图2B，高倍显微镜，标本显示无图案的“组样”表现，伴有大量有丝分裂和红细胞外渗。