Bortezomib Therapy in an Elderly Male with Multiple Myeloma

Bortezomib is a proteasome inhibitor effective in the treatment of multiple myeloma and other hematologic and solid tumors. Proteasome inhibitors interfere with protein homeostasis, arresting the cell cycle and leading to tumor cell apoptosis. Bortezomib-based therapies, which incorporate dexamethasone or melphalan and prednisone, are first-line treatment for high-risk multiple myeloma patients, as defined by cytogenetic testing. In-travenous dosing for bortezomib in this case is 1.3 mg/m2 for up to 9 cycles. Due to its action on the ubiquitous proteasome, bor-tezomib has variable adverse effects, including asthenia, nausea, diarrhea, anorexia, thrombocytopenia, anemia, and peripheral neuropathy.1 Peripheral neuropathy (usu-ally a small axonal, sensory neuropathy) is perhaps the most common nonhematologic toxicity, occurring in up to 40 % of patients.2 A less common neuropathy, ortho-static hypotension, is thought to be a drug-induced auto-nomic neuropathy, developing in 13-36 % of patients.2,3 Orthostatic hypotension has been observed in the popu