Small nodules in the lung
According to the NCCN (National Comprehensive Cancer Network) guidelines for lung cancer screening, the application of low-dose spiral CT for routine annual examinations in high-risk groups has been found to reduce lung cancer mortality by 20% and reduce mortality from any cause by 7% compared to chest radiograph physical examinations.
NCCN guidelines recommend annual low-dose spiral CT of the lungs for people at high risk for lung cancer. High-risk groups are defined as.
1. 55-74 years of age, are smoking or have quit smoking for less than 15 years, and have a smoking index greater than 30 pack-years (e.g., 1 pack per day for 30 years).
2. Those who are older than 50 years old, have a smoking index greater than 20 pack-years, and have a combination of one of the following conditions: history of tumor; history of lung disease; family members with lung cancer; occupational exposure to radon and carcinogenic substances (including arsenic, chromium, asbestos, nickel, cadmium, beryllium, silica and diesel fumes) in the residence.
The above high-risk groups of lung cancer are recommended to have annual low-dose spiral CT (LDCT) examinations for at least 2 years or until the patient is no longer suitable for complete treatment, while routine LDCT examinations are not recommended for other medium and low-risk groups.
Depending on the CT findings, different management measures are taken.
A, no pulmonary nodules: annual LDCT examination for a minimum of 2 years or until the patient is no longer suitable for complete treatment.
B, finding solid or partially solid nodules in the lungs (nodules without benign calcification, fatty or inflammatory manifestations).
a, <6mm, LDCT annually for a minimum of 2 years or until the patient is no longer a candidate for complete treatment.
b. 6-8 mm, LDCT at 3 months, and if no growth within 6 months, LDCT annually for a minimum of 2 years or until the patient is no longer suitable for complete treatment.
c. >8mm, consider PET/CT, if lung cancer is suspected, surgery or biopsy; do not consider lung cancer, review LDCT in 3 months, if no growth within 6 months, review LDCT annually for a minimum of 2 years or until the patient is no longer suitable for complete treatment.
The above is under dynamic observation, and if nodules are found to grow, surgical resection is recommended.
e. If an endobronchial nodule is found, LDCT should be repeated after 1 month (immediately if there is severe cough), and if it does not subside, fiberoptic bronchoscopy should be done to clarify.
3.Find pulmonary ground glass shadow or ground glass nodule, non-solid nodule.
a, <5mm, review CT within 12 months, if stable, LDCT annually for a minimum of 2 years or until the patient is no longer suitable for complete treatment. If there is an increase in size, LDCT or surgical excision may be considered for dynamic review in 3-6 months.
b.5-10mm, review CT in 6 months, if stable, annual LDCT for at least 2 years or until the patient is no longer suitable for complete treatment.
c.>10mm, review LDCT in 3-6 months, if stable, LDCT can be reviewed in 6-12 months, or biopsy or surgical resection.
If the nodule is found to be enlarged or solid during the above dynamic observation, surgical resection should be performed except for those with diameter <5mm, which can be considered for dynamic review of LDCT in 3-6 months.
Kim et al. reported that 75% of persistent ground glass shadows were confirmed to be malignant. The majority of lung cancers presenting as ground glass shadows are adenocarcinoma in situ, previously known as fine bronchoalveolar carcinoma, with a 100% postoperative survival rate at 5 years. Lung cancers that present as solid or mixed solid nodules are more aggressive and fast-growing lung cancers.