We found more CGRP-expressing sensory nerve fibers in the periosteum of the ipsilateral tumor–bearing bones than the contralateral bones, whereas there were no changes in the sprouting of sensory nerve fibers in the bone marrow (Fig 2A and B; neurofilament 200 (NF200) was used as a marker for sensory nerves). The gene discussed is CALCA; the disease is neoplasm.