Ground glass nodule 19mm in the posterior basal segment of the lower lobe of the left lung needs to improve the pathology biopsy to clarify the diagnosis, which can be treated with medication, surgery and so on. Pathology biopsy: 19mm ground glass nodule in the lung has the possibility of malignancy, and needs to improve the pathology biopsy to clarify its nature and decide the treatment plan. 1. Drug treatment: if the pathological result shows old nodules, no treatment is needed, regular review is enough; if it is inflammatory nodules, anti-inflammatory drugs such as cefixime and azithromycin can be used; if it is cancerous nodules, anti-tumor drugs such as carboplatin, cisplatin and etoposide can be used. 2. Surgery: If the nodule is malignant, according to its specific situation, those who can be operated should be operated to remove the lesion. The 19mm ground glass nodule in the posterior basal segment of the lower lobe of the left lung needs timely medical treatment, complete the relevant examinations, and actively treat the disease, so as to avoid delaying the condition.