string: For some analyses, a scale of immunopositive index was used as has been previously described [12]: 0 (no immunostaining); 1 (<10% lightly immunostained cells); 2 (<10% moderate-to-darkly immunostained cells); 3 (10‚Äì25% moderate-to-darkly immunostained cells); 4 (25‚Äì40% moderate-to-darkly immunostained cells).