Is pain in your shoulder a sign of lung cancer? Probably not. Cancer is rarely a cause of shoulder pain -- arthritis, bursitis, and tendinitis are much more likely reasons for it. But here’s why shoulder pain could have a link to some types of lung cancer.
Shoulder pain is the most common symptom of a type of cancer called Pancoast tumor. These tumors are rare. They only make up 3%-5% of lung cancer cases.
These tumors start in the upper part of one of your lungs but rarely have symptoms related to your breathing. They tend to spread to the ribs, vertebrae, nerves, or blood vessels in this area. When they spread, they can cause you to feel shoulder pain.
Pancoast tumors may not only cause shoulder pain, but also arm pain, muscle weakness, tingling skin, and a loss of feeling in the area. As they grow, the pain can spread to your upper back, between your shoulder blades, your arm, and even your armpit.
About 40% of people with Pancoast tumors get a condition called Horner’s syndrome. Severe shoulder pain is one symptom of the condition. It’s also called Pancoast syndrome.
When a Pancoast tumor spreads outside your lung, it can grow into and press against nerves nearby. This squeezing causes the shoulder pain, but also nerve-related symptoms like these on one side of your face:
- Drooping eyelid
- Pupil of your eye gets smaller
- Flushed skin
- Lack of sweating
Horner’s syndrome affects the side of your face where the tumor is. You may feel tingles or pricks in your hands too.
Mesothelioma is a rare form of cancer. It’s usually caused by long-term exposure to asbestos fibers in the air. Shoulder pain is a possible, but rare, early symptom of a type of this disease called pleural mesothelioma. It may be moderate to severe. If you have this disease, you may also feel that your shoulder joint just doesn’t move or work well.
Pleural mesothelioma affects the lining around your lungs. More common first symptoms of this condition are chest pain, a cough, and shortness of breath.
Metastatic or Advanced Lung Cancer
About half the time, a type of cancer called non-small-cell lung cancer (NSCLC) isn’t diagnosed until it spreads beyond your lungs. That’s called metastatic or advanced cancer.
When this happens, it can damage bones, internal organs, and nerves. In rare cases, it can affect your muscles too. It’s not typical, but intense shoulder pain may be one sign that this cancer has spread and damaged your muscles.
What Should You Do if You Have Shoulder Pain?
Most of the time, shoulder pain is caused by repeated movements of your joint, injury, fracture, or inflammation of soft tissues, not a tumor.
You should see your doctor for a thorough exam if you have shoulder pain that spreads to other nearby areas of your body, or other symptoms like arm pain, muscle weakness, or tingling. If you’ve been exposed to asbestos at work recently or further in the past, be sure to tell your doctor. Breathing in asbestos is the main cause of mesothelioma.
Imaging tests like MRIs, CT scans, or PET scans may show a Pancoast tumor or signs of mesothelioma.
Your doctor may need to do a needle biopsy to analyze tissue from the tumor or lung fluid to be sure it’s cancer and, if so, to see how advanced it is.