There are no specific symptoms in the early stages of lung cancer, and regular chest imaging can help detect early lung cancer. The most important thing to know is that you can’t be sure that you’re going to be able to get a good deal on your own. Obviously not, because some common diseases may also have similar imaging manifestations. In this article, we’ll take a look at each of them.
Tuberculosis
There are several types of tuberculosis, such as hilar lymph node tuberculosis, infiltrative lesions in the apical region of the lung, tuberculosis spheres, and cornu-like tuberculosis and tuberculous pleurisy. Some types have symptoms similar to lung cancer, such as tuberculous pleurisy which can also lead to pleural effusion.
However, tuberculosis mostly has relatively specific manifestations, such as low-grade fever and night sweats.
Specifically, tuberculosis spheres tend to develop slowly, mostly in young patients, without obvious clinical symptoms, and are located in the posterior part of the upper lobe or the dorsal part of the lower lobe of the lung, with relatively well-defined lesions, often with calcified spots within the lesions or surrounded by scattered tuberculosis satellite lesions.
Cavitary tuberculosis is most often seen on imaging as a central cavity with a relatively regular inner wall.
Pulmonary hilar lymph node tuberculosis is more commonly seen in adolescents, often with fever and other symptoms of toxic tuberculosis infection, and rarely with hemoptysis.
Cornular tuberculosis is also seen more often in young people, with marked signs of systemic tuberculosis toxicity.
The diagnosis is usually not difficult for doctors to make based on a combination of clinical and laboratory tests.
Inflammatory disease of the lung
Bronchopneumonia and lung abscess are common inflammatory lung diseases. Some patients with lung cancer can have obstructive pneumonia as a complication. Bronchopneumonia usually has an acute onset and is often characterized by high fever, coughing up purulent sputum, and even blood in the sputum. It is sometimes difficult for physicians to distinguish based on imaging data alone.
However, there are ways to differentiate. The most important thing is that the patient’s symptoms will improve after a period of anti-infection treatment, and the shadow of the lung will be absorbed more quickly. The doctor will be able to identify it more easily.
Lung abscess is relatively easy to distinguish. It is a purulent lesion of the lung tissue and is characterized by a rapid onset of symptoms of infection and toxicity, including chills, high fever, coughing, and coughing up large amounts of purulent sputum. When the lung tissue becomes septic and necrotic, a “cavity” can be formed. On CT and other imaging films, doctors can see that the walls of the cavity are thin and smooth; when the pus is not drained, there are often “fluid planes”; and there are inflammatory changes around the cavity. Based on these features, the doctor will make a diagnosis of lung abscess.
Intrapulmonary or mediastinal lymphoma
Intramural mucosa-associated lymphoma of the lung is not uncommon. It presents on imaging as an isolated mass shadow in the lung and is easily confused with lung cancer.
Lymphoma typically presents with prolonged fever and wasting; in addition to enlarged lymph nodes in the lungs, there is often enlargement of lymph nodes in superficial areas such as the neck and groin and deep areas such as the retroperitoneum, and often in combination with hepatosplenomegaly. It can be differentiated from lung cancer by superficial lymph node biopsy.
Benign tumors of the lung
Benign lung tumors such as malignant tumors, fibromas, and chondromas are morphologically difficult to distinguish from lung cancer. However, they are generally slow-growing and recurrent; the masses tend to be more regular in morphology on imaging, with no features such as lobulation or burr. Doctors will eventually confirm the diagnosis through pathological examination.
Pulmonary nodulopathy, vasculitis, etc.
Both of these diseases are often found occasionally on physical examination.
Pulmonary nodulopathy mostly presents with symmetrical enlargement of lymph nodes in the hilum bilaterally, as if they were potatoes. It has corresponding features in serology, such as angiotensin-converting enzymes (ACEs) that tend to be elevated.
Granulomatous vasculitis (e.g., Wegener’s granulomatosis) is an inflammation of small vessels that may present with fever, weight loss, malaise, arthralgia, and myalgia; imaging may show multiple lesions in both lungs or early nonspecific interstitial lung infiltrates followed by nodular or isolated masses, similar to the imaging features of lung cancer. However, vasculitis mostly has corresponding serologic features, such as positive ANCA (anti-neutrophil cytoplasmic antibody). Definitive diagnosis still depends on pathological examination.
Summary: When doctors encounter these lung images that are easily “confused” with lung cancer, they will be extra cautious and use other tools to help diagnose if necessary. All you need to do is have confidence and work with your doctor to complete the tests.
Co-reviewed by: Guangdong Provincial People’s Hospital, Guangdong Lung Cancer Institute, Dr. Wang Zhen, Deputy Chief Physician, Dr. Li Xuetao