Arm Pain Masks Advanced Lung Cancer Diagnosis
A patient's severe arm pain and inability to lift his arm led doctors to discover stage 4 lung cancer that had metastasized to the bone, highlighting how bone pain can mask advanced disease.
On July 2, 2026, Assoc. Prof. Dr. Sira Lohatyai, a thoracic surgeon known as Dr. Jae, posted a cautionary case on TikTok (@siradoctorlung) with the message: "Arm pain nearly unbearable—turned out to be stage 4 lung cancer."
Dr. Jae recounted a case where a patient presented with chronic arm pain and was later found to have bone destruction. X-ray imaging showed damage to the right upper arm bone, caused by cancer cells spreading to the bone. This finding indicated the patient had already reached stage 4 disease.
Lung cancer commonly metastasizes to bones, including the ribs, though this patient's cancer had spread to the arm. The persistent pain was so severe that the patient could not lift his arm, until ultimately, stage 4 lung cancer was diagnosed.
