Lymphoma beginning in bones

My husband's large cell lymphoma began in his r. humerus and is also in his l. hip and femur and bone marrow.  It is not in the lymph nodes, which is unusual.  Has anyone had a similar situation?  I understand the bones are part of the lymphatic family and only 1-3% of lymphomas begin in the bone.  He has had his first chemo tx and doing well -- no nausea.  But he has pain in his center spine where there was no evidence of lymphoma and it did not begin until after his chemo treatment.  We woud appreciate any information from someone who has had a similar case.  Thanks.