Is this really true that if you have very bad shoulder pain, it can be a sign of lung cancer? originally appeared on Quora, the place to gain and share knowledge, empowering people to learn from others and better understand the world. You can follow Quora on Twitter, Facebook, and Google Plus.

(Various types of) lung cancer can present in a myriad of ways. I’ve treated two patients in the last few months whose lung cancer presented with shoulder pain.

One of these had what is known as a Pancoast tumor. Her pain started as a minor ache which she mainly felt at night, then progressed to the point where she used ibuprofen during the day - every day. She saw her primary care doctor who gave her a steroid dose pack and when that didn’t help, he sent her for a shoulder x-ray. Just on the edge of the shoulder x-ray, the radiologist saw a mass in the apex of the lung. A CT scan showed a classic Pancoast tumor, which starts in the superior sulcus of the lung, where the nerves pass that go the the shoulder and arm. The pain required high doses of narcotics by the time it had been biopsied and staged. She saw a surgeon who thought it was not resectable, then saw me for radiation therapy. Her Medical Oncologist gave her weekly chemotherapy while I gave her 7 weeks of daily radiation therapy treatments. By the end of treatment, her pain was much improved (due to shrinkage of the mass - taking pressure off of the nerves). Three months later, her PET scan showed no more activity and we will continue to follow her as time goes on.

The other patient had a relatively small (garden variety) primary lung cancer, but it had spread via the blood stream to his cervical spine, squeezing the nerves going to the shoulder region. (When a nerve is compressed as it exits the spine, we experience pain as though it was coming from the place that nerve normally innervates.) This patient, like the one above, actually had nothing at all wrong with the bones or muscles of their shoulder - but they both presented with shoulder pain.

I’ve seen countless patients during my career who have presented with shoulder pain because the cancer had spread to the scapula (shoulder blade) or upper humerus (upper arm bone) - or to the spine at the level where the nerves go to the shoulder - or along the path of those nerves - like those described above. I’ve also seen it present as pain in every other bone in the body - as well as arthritis in every joint (due to a paraneoplastic process called hypertrophic pulmonary osteoarthropathy) - but I digress.

Obviously, there are a lot more common causes of shoulder pain than cancer, but when someone has unremitting, continually worsening pain in any part of the body, cancer is always in the differential diagnosis.

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