Clinical findings at diagnosis and clinical course in Case 2. (a) Papules on the back of her metacarpophalangeal and interphalangeal joints and periungual erythema. (b) Skin biopsy showed liquefaction degeneration at the dermal–epidermal junction (indicated by an arrow) and perivascular lymphocytic infiltration in the dermis (indicated by an arrowhead) (haematoxylin and eosin ×20). (c) Chest CT scan showing ground-glass opacity (indicated by a circle). (d) Because of the initial diagnosis of GvHD, we started the treatment with oral PSL (1 mg/kg/day) and CsA. Skin symptoms were aggravated during the course of tapering immunosuppressants. The patient was finally diagnosed as a CADM based on pathological findings and the positivity of anti-MDA-5 antibody. In anticipation of therapeutic impact on both lymphoma and CADM with ILD, we started the treatment of rituximab (375 mg/m2, once a week) ∼270 days after CADM onset. After four cycles of rituximab, titres of anti-MDA-5 antibody and KL-6 were considerably decreased, in parallel with amelioration of skin and lung symptoms. About 330 days after the CADM onset, the level of lactate dehydrogenase in sera was markedly increased, and lymphoma was again exacerbated. DLI was resumed (total six times, 5.0 × 106–4.0 × 107 CD3+ cells/kg) with a combination of four cycles of rituximab. Although she remained free of skin and lung symptoms, she died of lymphoma ∼450 days after CADM onset.
