Abstract
A 73-year-old man had undergone treatment for diabetes mellitus, hypertension, and dyslipidemia in another
hospital. He was referred to our hospital after monoclonal immunoglobulinemia was discovered during a routine
medical examination. He was diagnosed with multiple myeloma (immunoglobulin G [IgG]-κ type, Durie–Salmon
stage IIA, International Staging System stage I) and was observed without therapy. However, because of an increasing IgG level (6,715 mg/dl), treatment with once-weekly intravenous bortezomib at 1.3 mg/m2
was initiated.
Two days after the sixth bortezomib administration, he complained of frequent vomiting, and the diagnosis of
paralytic ileus was made. Because bortezomib-induced ileus was suspected, the bortezomib was discontinued
thereafter. Bortezomib-induced paralytic ileus has been reported in patients treated with vincristine and/or thalidomide as well as those undergoing twice-weekly bortezomib administration. Clinicians should be aware that
once-weekly bortezomib can induce ileus in patients without previous treatment.
