Table 2 Comparison of pathological manifestations between the patients in remission and patients with relapse

Number of IgG4⁺ plasma cells/HPF

50 (25–120)

70 (40–290)

0.013^*

Ratio of IgG4⁺ cell/IgG⁺ cell (%)

40.0 (30.0–56.0)

40.7 (40.0–59.5)

0.644^*

Severe IgG4⁺ plasma cell infiltration (≥60/HPF in visceral organs or ≥200/HPF in head and neck organs)

21 (44.7%)

18 (85.7%)

0.002^**

Fibrosis

39 (83.0)

18 (85.7)

0.777^**

Storiform fibrosis

7 (14.9)

2 (9.5)

0.546^**

Obliterative phlebitis

16 (34.0)

7 (33.3)

0.954^**

Eosinophilic infiltration

5 (10.6)

1 (4.8)

0.430^**

Lymphoid follicle formation

18 (38.3)

3 (14.3)

0.048^**

Germinal center formation

5 (10.6)

1 (4.8)

0.430^**