B2M and neoplasm: The frequencies of positively stained areas of the cell membrane and cytosol within the tumor tissue are as follows: β2M 8.2% (cell membrane) and 39.84% (cytosol); CD1d 6.72% (cell membrane) and 53.83% (cytosol); and CD1b 12.39% (cell membrane) and 55.18% (cytosol) (Figure 2G).