Serum myosin light chain determinations in patients with inflammatory myopathy--a preliminary report.

(nodular sclerosis). Further investigations established that his tumour was stage II A. Accordingly, methotrexate was discontinued and a full course of radiation therapy delivered immediately. After six months of follow up the patient had no evidence of disease relapse. The table summarises nine reported patients2" who developed malignancies while receiving methotrexate therapy. Patient 74 shows striking similarities to ours, in that both developed nodular sclerosis Hodgkin's lymphoma after presenting with dermatomyositis. However, causality in the first case was well established, given the regression of the tumour observed after methotrexate discontinuation. It is unclear if our patient's dermatomyositis was an early manifestation of Hodgkin's lymphoma or a consequence of methotrexate therapy. In support of the latter, our patient showed: a short interval between development of the rash and of the tumour; a tumour which is relatively uncommon among patients with dermatomyositis and malignancy; and clinical and histological similarities with another reported patient in whom the relationship between tumour development and methotrexate use was proven.4 We propose that careful examination of the lymph nodes, using sensitive techniques, should be undertaken in adolescents with dermatomyositis who are about to receive low dose methotrexate therapy.