A 12mm solid nodule with lobulation may be caused by fungal infection of the lungs, tuberculosis, and lung cancer. It can be treated with general therapy, medications such as fluconazole, and surgery if necessary. 1. Fungal infection of the lungs: when there is fungal infection in the lungs, 12mm solid nodule with lobulation can occur. If it is Candida albicans infection, it can be treated with fluconazole; if it is Aspergillus infection, it needs to be treated with voriconazole for antibiotic therapy. 2. Tuberculosis: It is often accompanied by cough, sputum, blood in sputum and weight loss. The main treatment is isoniazid, rifampicin, pyrazinamide and other regular medications. 3. Lung cancer: 12mm solid nodules with lobulated malignancy are more likely to be present, some of which are asymptomatic. Typical symptoms of lung cancer are cough, sputum, low-grade fever, chest pain, and blood in sputum. The typical symptoms of lung cancer are cough, sputum, low-grade fever, chest pain, and blood in sputum. The treatment is mainly surgical resection and radiotherapy. The 12mm solid nodule is lobulated, and there are other possibilities, such as vasculitis, etc. It is recommended to consult a doctor in time to find out the cause and treat the cause. The above medication should be taken in accordance with the doctor’s prescription.