Should prophylactic granulocyte-colony stimulating factor be used in multiple myeloma patients developing neutropenia under lenalidomide-based therapy?

Lenalidomide combined with dexamethasone has significant clinical activity in the treatment of multiple myeloma (MM). In previous clinical trials lenalidomide-induced neutropenia was a frequent side-effect, often leading to treatment delays and dose reductions. We describe three MM patients treated with lenalidomide plus dexamethasone, which developed grade 3/4 neutropenia during the initial cycles, but without serious infection. Administration of granulocyte-colony stimulating factor (G-CSF) for 3 d prevented further neutropenia, treatment delays, dose reductions, or infectious complications during the following cycles. Consequently, G-CSF could be effective in preventing further neutropenia-related complications without compromising treatment efficacy in MM patients with lenalidomide-induced neutropenia.