A 46-year-old woman was referred to our hospital for evaluation of a recent history of progressively severe nausea and easy fatigability on walking. She was noted to have had an atomic bomb exposure at a distance of 2km from the hypocenter. A diagnosis of multiple myeloma (IgG, L-type) was established. However, the radiation dose affected to her was estimated too much low level to conclude its direct effect to cause such an impairment. Twenty six days after admission to the hospital, a corticosteroid and melphalan therapy was started on a daily schedule for seventy seven weeks. Immunological findings obtained on admission were revealed lowered cell-mediated immunity, such as negative tuberculin reaction, 37.5% T cell in sub population of lymphocytes and 45% lymphocytes transformation with PHA. After 9 months of treatment she was found to have basal cell carcinoma of skin and rectal adenocarcinoma further 10 months later, of which she died during the remission of the primary disease. It may be assumed that antecedent abberances of the immunological surveillance mechanism associated with preceding myeloma might be causally involved in the successive production of three kinds of neoplasm. Such an immunoregulatory suppression strikingly concerned to the antineoplastic agents against myeloma was thought to be possibly responsible for the development of the ensued neoplasms. For improving prognosis of this disease it may depend not only on early detection, but also appropriate treatment of ensued malignant neoplasm.
