The current early diagnosis rate of lung cancer in China is very low, with a 5-year survival rate of 15.6%.
Early lung cancer often presents as lung nodules. Early stage lung cancer is often manifested as lung nodules, but the current treatment level is difficult to make timely and accurate diagnosis of most lung nodules; at the same time, there is a lack of scientific differential diagnosis methods for nodules, resulting in delayed diagnosis and loss of the best treatment opportunity.
What is the malignancy rate of lung nodules?
The malignancy rate of lung nodules is about 20%; if men who smoke find nodules in their lungs and do not quit smoking continue to smoke, the malignancy rate of nodules is about 20 times higher than that of nonsmokers.
What are the possible diseases of nodules?
Benign tumors include: malignant tumors, adenomas, lipomas, infectious granulomas, tuberculosis, histoplasmosis, coccidioidomycosis, and pedunculosis.
Benign non-neoplastic diseases: occlusive fine bronchitis with mechanized pneumonia, abscess, silicosis, fibrous degeneration/scar, hematoma, pseudotumor, spherical pneumonia, pulmonary infarction.
Malignant tumors: bronchogenic lung cancer (adenocarcinoma, large cell carcinoma, squamous carcinoma, small cell carcinoma), carcinoid tumor, pulmonary lymphoma.
Metastatic tumors: colon cancer, breast cancer, kidney cancer, head and neck tumors.
How can CT films diagnose the benignity or malignancy of pulmonary glassy nodules?
CT reading is one of the tools, but its sensitivity and specificity are both limited. To improve the diagnostic accuracy, we have to rely on the rest of the information: medical history, calculation of the probability of malignancy, and the massive amount of information of CT for deep mining.
For those with ground glass shadows ≤5 mm in diameter: further appropriate evaluation is recommended (grade 2C).
Those with a ground glass shadow diameter >5 mm: annual CT of the chest is recommended.
It is important to note that.
1, CT follow-up of non-solid nodules should be performed with a thin-layer scanning technique at the nodule.
2. enlargement of non-solid nodules or an increase in the realistic component of the nodule is usually indicative of malignant transformation and requires further evaluation and/or consideration of resection.
3. if the non-solid nodule is >10 mm in diameter and the patient is unwilling or unable to undergo subsequent non-surgical biopsy and/or surgical resection, early follow-up is recommended beginning 3 months thereafter
4. If the patient also has a life-threatening comorbidity and the lung nodule is considered to be of low malignancy that will not affect survival soon; or if it may be an inert lung cancer that does not require immediate treatment, follow-up may be limited or less frequent.
What is the next step in the treatment decision when a small nodule is found?
If a small nodule cannot be identified as benign or malignant and is larger than 1 cm, the choice of further treatment decision depends on the communication between the physician and the patient, as the patient’s personal preference also plays a key role in the treatment of the disease. If the patient actively requests, surgery may be considered and thoracoscopic surgery would be preferred, but the patient should be informed that doing so, while avoiding missed misdiagnosis, may result in overmedication.
What is the management of small asymptomatic CT <0.5CM ground glass nodules?
Periodic review is usually recommended, and surgery is recommended if nodules are found to grow, or if tumor features such as increased density are observed. Since nodules < 0.5cm are usually not metastatic even if they are tumors, the final diagnosis of lung cancer at regular review will not miss the best time for treatment. If the patient insists on surgery, it is possible to cause over-medication although avoiding misdiagnosis by missing the diagnosis.
Is there any difference in the management plan for nodules with or without smoking history?
Those with a history of smoking need to be followed up more frequently, e.g. 6-month follow-up CT for non-smokers, i.e. 3-month follow-up for smokers.
Evaluation and management of mGGO (>50% ground glass)
1. Single partial solid nodule ≤8 mm in diameter
CT surveillance at 3, 12 and 24 months is recommended, with subsequent conversion to routine annual examinations for those without change.
The following need to be noted in monitoring.
(1) CT follow-up examinations of partially solid nodules should be performed with a thin layer scanning technique at the nodule.
(2) Enlargement of partially solid nodules or an increase in the solid component is usually suggestive of malignancy and requires further evaluation and/or consideration of resection.
(3) If the non-solid nodule is >10 mm in diameter and the patient is unwilling or unable to undergo follow-up non-surgical biopsy and/or surgical resection, early follow-up is recommended starting after 3 months.
(4) If the patient also has life-threatening comorbidities and the lung nodule is considered to be of low-grade malignancy that will not affect survival soon or may be inert lung cancer that does not require immediate treatment, the follow-up period may be limited or reduced in frequency.
2. Some solid nodules >8 mm in diameter
Repeat chest CT at 3 months is recommended, followed by further evaluation with PET, non-surgical biopsy and/or surgical resection if the nodule persists (grade 2C).
It is important to note that.
(1) PET should not be used to characterize partially solid lesions with a solid component ≤8 mm.
(2) Non-surgical biopsy can be used to establish the diagnosis and to help localize subsequent surgical resection in combination with techniques such as placement of localization wires, implantation of radioactive particles, or injection of dye.
(3) The possibility of malignancy cannot be excluded if the diagnosis is still not clear after non-surgical biopsy.
(4) Further PET evaluation, non-surgical biopsy and/or surgical resection may be considered for some solid nodules >15 mm in diameter.