There are more than ten kinds of detailed classifications of lung cancer, and each has its own characteristics in terms of treatment, so it is better to have further examinations, such as tracheoscopy and puncture biopsy, to clarify the pathological type. Unless the lesion is particularly typical, further examination such as PET-CT is sometimes needed to clarify. Then, further examination is needed to check whether there are metastases from other sites. If the intrahepatic lesion is finally determined not to be metastasis, and no other metastasis is found after examination, surgery can be considered if the intrapulmonary lesion can be operated, and radiotherapy can be considered if it cannot be operated (if the lesion is small, stereotactic radiotherapy, such as radio-wave knife, can be used), or combined with chemotherapy according to the condition. If there is a single metastasis in the liver and no metastases are found in other parts of the body, more aggressive treatment can be considered, such as combined radiotherapy and chemotherapy. If there are multiple metastases in the liver or metastases in other parts of the body, then chemotherapy is the main treatment, combined with radiotherapy if necessary.