Unexplained Right Shoulder Pain May Indicate Liver Cancer Through Referred Pain

Unexplained pain in the right shoulder can sometimes indicate liver cancer due to a process known as referred pain, according to medical experts. Referred pain occurs when issues in one part of the body, such as the liver, cause discomfort in another area, like the shoulder. The American Cancer Society has linked pain in the right shoulder blade to early signs of the disease.

Published case reports have documented shoulder pain as a symptom of hepatocellular carcinoma (HCC), the most common type of primary liver cancer. Mark Ashamalla, MD, chief of radiation oncology at Episcopal Health Services in New York, explained that liver cancer can produce pain felt in the right shoulder despite no issues in the shoulder itself.

“The liver sits high in the right upper abdomen, just under the diaphragm, which is the muscle that helps us breathe," he told Fox News Digital. "If a liver tumor grows large enough or is positioned in a way that stretches the liver’s outer covering or irritates the diaphragm, it can trigger nerves in that area.”

The brain may interpret these nerve signals as originating from the right shoulder or shoulder blade. Ashamalla noted that this differs from phantom pain, which involves sensations in amputated body parts. Instead, the underlying issue remains in the liver, with nerve pathways directing the pain sensation to the shoulder.

Most instances of shoulder pain arise from musculoskeletal conditions, including rotator cuff problems, injuries, arthritis, nerve issues, muscle strain, tendon problems, or poor posture. Such pain typically follows injury, overuse, awkward sleeping positions, heavy lifting, or repetitive motions.

It often worsens with specific arm movements and may involve tenderness, stiffness, weakness, or reduced range of motion.

In contrast, referred pain from liver cancer does not usually follow orthopedic patterns. Ashamalla listed indicators that may suggest referred pain, including pain that persists without clear cause, does not improve with typical shoulder treatments, or occurs without injury or overuse.