Hello, From the history you have given, ( a really lucid one) , the soft mass below your shoulder blade seems to be similar to a lipoma
, which is nothing but accumulation of fat. The exact diagnosis can be given by the attending physician on examining it in detail. And your headaches
and the numbness
and burning sensations in the arm all seem to be the direct effects of the cervical disc degeneration which you have already been addressed about. So a good posture and physiotherapy
should help you . The chest pain
aggravated on movement can mostly be a musculoskeletal one with inflammation of the rib joints. Though these symptoms do not seem to be associated with the family history of cancers, I would suggest you to get evaluated for the swelling , probably an ultrasound
of the swelling can give a clue. The xrays for the neck and chest can rule out any other suspicions. Talk to your physician about the family history of cancers and he might deem it necessary to screen you for the same if he suspects any from the complete history and examination findings. you can be reassured about the concerns of a
Cancer . Take care! Hope everything goes on well!