I was diagnosed with lung nodules. What should I do?

Author: Gao Xuehan Peking Union Medical College Hospital

Zhou Mengxin Peking Union Medical College Hospital

Reviewer: Guo Chao, deputy chief physician, Peking Union Medical College Hospital

Li Danqing, Chief Physician, Peking Union Medical College Hospital

"Lung nodules" is a very popular medical term nowadays. With the improvement of people's health awareness, physical examinations have become a necessary means to monitor one's health status. Chest CT is an important part of physical examinations. Many people suddenly find that they have "lung nodules" after receiving their physical examination reports. Due to lack of understanding of lung nodules, some patients will become anxious and even seek medical treatment in a hurry. So, what should we do if lung nodules are found during the examination?

Figure 1 Copyright image, no permission to reprint

1. What are lung nodules?

Pulmonary nodules are an imaging definition, referring to small lesions (≤3 cm in diameter) that are completely surrounded by lung parenchyma and have clear boundaries. In simple terms, they are abnormal lesions in the lungs found during imaging examinations. Many lung diseases may manifest as pulmonary nodules, of which about 99% are caused by benign diseases. Therefore, pulmonary nodules are not as scary as imagined.

If lung nodules are found during examination, please do not panic and go to the thoracic surgery or respiratory medicine department in time to have a professional doctor diagnose and treat you to prevent the omission and deterioration of malignant lesions.

2. Medical treatment

After a lung nodule is discovered, the first thing to do is to have a professional doctor make a preliminary diagnosis, which includes the following two steps:

(1) Check in advance and choose the appropriate department to visit. The departments that can evaluate lung nodules mainly include thoracic surgery and respiratory medicine. Thoracic surgery uses surgery as the main means of diagnosis and treatment. Therefore, in terms of lung nodules, thoracic surgery mainly evaluates whether lung nodules require surgery and whether surgery can be performed. Respiratory medicine uses non-surgical methods (mainly drug treatment) as the main means.

The functions of each department are diverse and complex. Different departments have different focuses on diagnosis and treatment, and the names of departments in different hospitals may also be different. Therefore, before seeing a doctor, you can browse the official website of the hospital you plan to visit, check the range of diseases and main diagnosis and treatment methods involved in different departments, and choose the most suitable department for treatment.

Figure 2: Outpatient visit to the Department of Thoracic Surgery or Respiratory Medicine (copyrighted images are not authorized for reproduction)

(2) It is recommended that patients be present at the first visit and provide a comprehensive and high-quality chest CT scan. Doctors can directly communicate with patients to answer many of their concerns, allowing them to feel involved and thus alleviating their fear of the disease itself.

3. Nodule Assessment

The evaluation of pulmonary nodules in thoracic surgery mainly involves: clinical manifestations and medical history, chest CT features and other auxiliary examinations.

1. Clinical manifestations

Evaluation of clinical manifestations and medical history should include the following:

(1) Chief complaint, symptoms and treatment status: such as whether the patient has fever, cough, sputum and other discomforts, whether the patient has chest tightness, chest pain, dyspnea, etc., whether the patient has fever, whether anti-infection treatment or traditional Chinese medicine treatment is received, and the treatment effect.

(2) Underlying diseases: such as whether the patient suffers from hypertension, heart disease, diabetes, or other malignant tumors.

(3) Work and life habits: such as whether the individual smokes, how many years of smoking, and how much he or she smokes; whether the individual is exposed to harmful substances such as dust, asbestos, and ionizing radiation in the work environment; whether the individual is exposed to oil fumes and passive smoking in the living environment.

(4) Family history: such as whether any immediate family members have malignant tumors.

2. Chest CT imaging features

The imaging features of chest CT are the most important part of the evaluation of lung nodules. Doctors can make a preliminary judgment based on the imaging features of lung nodules. Therefore, it is very important to provide comprehensive and high-quality chest CT films. Specifically, all chest CT films (from the first to the most recent) should be provided to doctors for a comprehensive assessment of nodules.

The characteristics that need to be assessed mainly include the following:

(1) Nodule size: The larger the nodule, the higher the risk of malignancy. For nodules larger than 2 cm, there is a 50% or greater chance of malignancy. For lung lesions larger than 3 cm, they are called "lung tumors" rather than "lung nodules" and have a higher probability of malignancy.

(2) Nodule morphology: Nodules with irregular shapes, rough edges (burrs, lobes), and those that pull on the pleura are usually more likely to be malignant.

(3) Nodule density and solid components: According to different densities and solid component contents, pulmonary nodules can be divided into solid nodules, partially solid nodules and pure ground glass nodules. Smaller (≤8 mm) solid density nodules are usually benign. Compared with solid nodules, partially solid nodules have a higher risk of malignancy.

(4) Changes in nodules: Enlargement of lung nodules is an independent risk factor for malignant tumors. Most solid malignant nodules double in size in 20 to 400 days. The doubling time of ground glass nodules may be longer. It should be noted that the assessment of nodule enlargement is mostly based on manual measurement, which is prone to errors. Usually, changes of less than 1.5 mm are considered to be caused by errors.

Different imaging features have a certain reference value for judging the nature of nodules, but they are not absolute. In addition, the judgment of the nature of nodules mainly comes from the doctor's experience and will be affected by many interfering factors (such as the quality of CT films, the accuracy of information provided by patients, etc.). The diagnosis given by the doctor is based on the empirical judgment of the data and the condition, rather than the final diagnosis. The only way to confirm lung nodules is to obtain nodule tissue for pathological examination (such as puncture or surgery).

3. Other auxiliary examinations

Depending on the characteristics of different patients, doctors may ask patients to do some other auxiliary examinations. The following table lists the examinations that patients with lung nodules may need to undergo during the diagnosis and treatment process and their main purposes.

It should be noted that the tests in the table are applicable to different situations, and you need to follow the doctor's advice on which one to do. Only when various tests complement and confirm each other can the doctor give a more accurate diagnosis and choose the most suitable treatment plan for the patient.

IV. Summary

(1) If a lung nodule is found during examination, the patient should first be seen by a relevant department (usually thoracic surgery or respiratory medicine) for evaluation by a professional doctor.

(2) When visiting the doctor, please bring complete and high-quality chest CT films and other auxiliary examination reports; it is recommended that patients visit the doctor in person.

(3) The doctor will make a preliminary diagnosis and recommendations based on the patient’s clinical manifestations, the imaging characteristics of the lung nodules, and the results of other auxiliary examinations.

References

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