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How can lung cancer first be discovered after it has spread to another part of the body?
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respiratory disease
The bronchioles of the lungs are the site where oxygen is exchanged for carbon dioxide during the process of respiration. Inflammation, infection, or obstruction of the bronchioles is often associated with acute or chronic respiratory disease, including bronchiectasis, pneumonia, and lung abscesses.
Lung cancer is frequently discovered only after it has metastasized because symptoms often do not appear until the disease has reached an advanced stage. When the cancer spreads to distant sites, the initial signs of the disease may be unrelated to the lungs, leading patients to seek medical attention for symptoms caused by secondary tumors.123
Common ways lung cancer is first identified through metastasis include:
- Bone Involvement: Patients may present with a hip fracture or localized bone pain caused by metastatic deposits.213
- Neurological Symptoms: Intracranial metastases can cause headaches, abnormal mental function, or behavioral changes. Additionally, peripheral neuropathy—which may manifest as sensory changes in the legs—can be a presenting sign.23
- Liver Dysfunction: Metastasis to the liver may result in jaundice.23
- Lymph Node Enlargement: Swelling of lymph nodes, particularly those above the collarbone in the neck, often prompts a clinical examination that leads to the discovery of the primary lung tumor.23
- General Indicators: In some cases, the first signs are nonspecific, such as unusual fatigue, malaise, or unexplained weight loss.23