A Pulmonary Nodule Is Not Lung Cancer: Follow Up Regularly and Do Not Panic
As Chinese residents pay increasing attention to health check-ups, the detection rate of pulmonary nodules has risen significantly compared with before. Many people feel panic after being found to have a pulmonary nodule, especially those who have cancer patients around them or who have already been diagnosed with other cancers.
But in fact, being found to have a pulmonary nodule does not mean lung cancer or pulmonary metastasis. Although there are as many as 700,000 new lung cancer patients in China every year, according to statistics from the National Health Commission, more than 93% of pulmonary nodules detected at medical institutions in China are ultimately determined to be benign. Therefore, the pulmonary nodules detected in medical institutions for most people are very likely benign.
The author has previously written several articles specifically about pulmonary nodules, introducing various common questions about them; see the author's articles "Pulmonary Nodule Basics 1," "Pulmonary Nodule Basics 2," "Pulmonary Nodule Basics 3," and "Pulmonary Nodule Basics 4." In those four long articles, the author introduced the knowledge about pulmonary nodules quite completely, so this article will not repeat it.
What should be done after a pulmonary nodule is found? This is one of the questions I am most often asked in daily practice. Authoritative bodies such as the State Council, the National Health Commission, and the Chinese Medical Association have issued dedicated guideline documents. The most important and practically valuable of these for ordinary people are the "Lung Cancer Screening and Early Diagnosis and Treatment Protocol (2024 Edition)" and the "Chinese Expert Consensus on the Diagnosis and Treatment of Pulmonary Nodules (2024 Edition)." It is recommended that everyone with pulmonary nodule problems read these two guidelines carefully.
These guidelines were compiled by the most experienced clinicians and researchers in China based on Chinese clinical data on pulmonary nodules, and they are more suitable for Chinese residents than similar guidelines issued by other countries. These guidelines are updated regularly, and newer editions may be released in the future.
According to the "Chinese Expert Consensus on the Diagnosis and Treatment of Pulmonary Nodules (2024 Edition)," people aged ≥40 who meet any of the following criteria are a high-risk population for lung cancer and are recommended to undergo a low-dose spiral CT examination once a year:
Smoking index ≥400 pack-years; a history of environmental or high-risk occupational exposure (such as contact with asbestos, beryllium, uranium, radon, etc.); concurrent chronic obstructive pulmonary disease, diffuse pulmonary fibrosis, or a prior history of tuberculosis; a prior history of malignancy or a family history of lung cancer, especially a family history in first-degree relatives (parents, children, and siblings).
Therefore, if you have the above high-risk factors, you may have a low-dose spiral CT of the chest every year to observe changes in the nodule. The doubling time of a malignant nodule is about 30-400 days. If it is a solid pulmonary nodule and no growth is seen over more than 2 years of follow-up, it is generally considered benign; if it is a ground-glass nodule, the follow-up period should exceed 2 years.
A nodule that enlarges rapidly within a short period (such as days or within a month) is usually not considered a tumor. However, if during follow-up the diameter increases with a doubling time consistent with tumor growth, the lesion enlarges or remains stable but is accompanied by newly appearing solid components, the lesion shrinks but is accompanied by the appearance or increase of solid components, the angiogenic features match the typical pattern of a malignant pulmonary nodule, or morphological abnormalities such as lobulation, spiculation, or pleural indentation appear, malignancy should be highly suspected.
Benign pulmonary nodules only require regular follow-up observation and no treatment; nodules of unknown nature require a detailed evaluation and follow-up plan. Generally speaking, nodules with a diameter no greater than 5 mm only need annual follow-up, while larger nodules or those with suspicious features may require shorter follow-up intervals, with re-examination every 3 or 6 months, as determined by the doctor based on the patient's condition.
The appearance of pulmonary nodules in cancer patients does not necessarily mean metastatic lesions; risk-stratified management can be carried out according to the above principles, with regular re-examination. The human body has many benign nodules, especially in people over the age of 40, because for various reasons (such as infection or immune problems), many benign nodules may appear in the body, and these nodules should not be treated as malignant nodules.
Overly hasty treatment of nodules can sometimes cause unnecessary tragedy. The author once encountered an elderly lung cancer patient in a certain area of Xinjiang who had a tiny nodule in the brain. The patient had a history of cerebral hemorrhage in middle age, and the nodule had remained unchanged after continuous observation for many years; such nodules are mostly old benign nodules. But because the patient had dizziness, he was inexplicably given brain radiotherapy at a local hospital and unfortunately died soon after treatment. This is a typical case of destructive treatment brought about by excessive fear of a nodule.
Some people also fear the radiation from low-dose spiral CT and dare not undergo regular re-examination. In fact, low-dose spiral CT is not that scary. Patients may refer to the "Chinese Guidelines for Low-Dose CT Screening for Lung Cancer (currently the latest is the 2023 edition)" for regular re-examination. Scientific monitoring can effectively reduce the risk of death from lung cancer and also alleviate the anxiety caused by the nodule; the benefits outweigh the drawbacks.