Figure 1
Tumors assigned into three grades depending on the number of PDCs. Arrowheads indicate poorly differentiated clusters (PDCs). (a) For G1, four clusters are observed; (b) for G2, six clusters are observed regardless of cluster size; and (c) for G3, more than ten clusters are observed under × 20 objective lens (0.950 mm2 field of vision). The scale bar indicates 100 micrometers.