Figure 1: Time course of tocilizumab-induced cutaneous manifestations, treatment protocol, and histopathology. (A) Treatment course of the present case. The patient received TCZ 3.5 mg/kg/4wks with MTX 7.5 mg/wk for the first 20 infusions and then TCZ monotherapy. (B) Clinical photographs of the change in the skin of the patient's left forearm, extensor side (a-c), and abdomen (d-f). (g) Rete ridge elongation and suprapapillary plate thinning. Perivascular inflammatory cell infiltration in the dermal papilla and upper dermis (H and E, ×50). (h) Confluent parakeratosis with prominent neutrophilic infiltrates (H and E, ×200). (i) Prominent Munro microabscess (H and E, ×400). (j) Prominent superficial dermal vascular proliferation and dilatation (CD31, ×100). RA: Rheumatoid arthritis, TCZ: Tocilizumab, MTX: Methotrexate, DMARDs: Disease-modifying anti-rheumatic drugs, H and E: Hematoxylin and eosin.