While the lungs themselves do not have pain receptors, it is not uncommon for some lung conditions to present as back pain as an early symptom, states About.com. Back pain often has many other causes unrelated to the lungs, but unremittent pain can also be a sign of lung cancer.
Nerve endings in the back can be irritated by the presence of cancer cells in the chest wall or lining of the lungs, explains About.com. Signals are sent to the brain that are interpreted as back pain. A cancerous tumor itself can press on and create pressure in areas of the back. Cancer that has metastasized to the bones in the spine can also result in back pain.