What is a Lung Nodule? Symptoms and Treatment

Ingredients

What is a Lung Nodule?
What are the Symptoms of Lung Nodule?
What Causes Nodules in the Lung?
Causes Due to Infections (Granulomas)
Inflammatory and Autoimmune Diseases
Benign Tumors (Hamartoma etc.)
Malignant Nodules and Lung Cancer
Lung Nodule Treatment and Surgical Approaches
Follow-up (Wait and See) Process
Closed Lung Surgery (Nodule Removal with VATS)
Surgical Intervention for Biopsy
Frequently Asked Questions
Does Every Lung Nodule Turn Into Cancer?
Is a 3 mm or 5 mm Lung Nodule Dangerous?
Does a Nodule in the Lung Go Away on Its Own?

Lung nodules are small formations located within the lung tissue, which have a different density than the normal lung structure and are usually less than 3 centimeters (30 mm) in diameter.

With the widespread use of modern radiological imaging techniques, these structures, which are detected incidentally in many patients today, are observed as a “spot” or “shadow” in the lung parenchyma.

Although not every nodule detected means a disease, it is vital that these formations are meticulously analyzed by a specialist thoracic surgeon and their biological character determined.

What is a Lung Nodule?

In its medical definition, lung nodules are round or oval formations located in the spongy tissue of the lung, surrounded by air-containing lung tissue, and whose borders can be relatively distinguished.

The size of the nodules is the most critical criterion in the diagnosis and follow-up process; Formations larger than 3 centimeters are no longer called nodules but “masses”, which usually require further examination.

Nodules can be seen as a single focus (solitary pulmonary nodule) or as multiple foci scattered in different lobes of the lung.

What are the Symptoms of Lung Nodule?

Lung nodules often do not show any clinical symptoms because they are small in size and usually located in the deep tissues of the lung.

The vast majority of patients learn about these nodules completely by chance on computed tomography (CT) taken due to another health problem (heart check, check-up or trauma).

However, if the location of the nodule is close to a large airway or its speed is increasing, it may rarely be accompanied by the following symptoms:

Mild Cough: Unexplained dry cough that develops due to airway irritation.
Chest or Back Pain: Stinging sensation when breathing if the nodule is located close to the pleura.
Shortness of Breath: In very rare cases, it can occur when the nodule affects the main bronchi.

In most cases, the absence of symptoms does not mean that the nodule is “innocent”; therefore, radiological characterization takes precedence over clinical complaints.

What Causes Nodules in the Lung?

Since the lungs are organs open to the external environment, many external factors that are exposed throughout life can leave permanent scars on the lung tissue.

A detected nodule can be part of an active process, or it can be a “scar” of an infection that took place decades ago.

The main causes of nodule formation are grouped into four main groups.

Causes Due to Infections (Granulomas)

In regions where tuberculosis (tuberculosis) is endemic, such as Turkey, the most common cause of nodules is calcified tissues left by previous infections.

Mantate infections (histoplasmosis, etc.) or cured foci of pneumonia can leave small, hardened nodules called “granulomas” in the lung tissue.

These structures are usually static and continue to remain in the lung without any change throughout the patient’s life.

Inflammatory and Autoimmune Diseases

Some rheumatic or systemic diseases in which the body develops a defense mechanism against its own tissues can lead to the formation of nodules in the lung.

Sarcoidosis: It is a disease characterized by small cell deposits in the lungs and lymph nodes.
Rheumatoid Arthritis: Although it is a joint disease, it can form “rheumatoid nodules” in the lungs.
Wegener’s Granulomatosis: It is a condition that progresses with vascular inflammation and can cause cavities (with a cavity in the middle) nodules in the lung.

Benign Tumors (Hamartoma etc.)

Not every tumor in the lung is cancer; Some formations are cell accumulations that grow on their own, do not damage the surrounding tissue and do not have the ability to spread.

Hamartomas, the most common benign tumor, are formed when the normal components of the lung (cartilage, fat, epithelium) come together in an irregular manner.

Such nodules usually show a characteristic “popcorn” style calcification (calcification) on tomography and do not require surgical intervention.

Malignant Nodules and Lung Cancer

The main purpose of nodule management is to catch malignant ones (cancerous cell accumulations) at an initial stage.

Malignant nodules can take two forms:

Primary Lung Cancer: They are nodules that originate directly from the lung cell and grow.
Metastatic Nodules: They are foci formed when cancer in another organ of the body (breast, colon, kidney, etc.) spreads to the lungs through the blood.

Malignant nodules usually tend to have irregular borders, a tendency to grow rapidly and special radiological appearances that we call ground glass views.

Lung Nodule and Cancer Distinction: Which Nodules Are Dangerous?

Not every nodule detected in the lung has the same risk of cancer; When making this distinction, physicians evaluate the morphological characteristics of the nodule and the patient’s risk profile (smoking history, age, genetics) together.

There are certain radiological criteria that distinguish potentially dangerous nodules from innocent ones.

Nodule Size and Shape (Mass vs. Nodule Distinction)

As the size of the nodule increases, the probability of it being malignant increases statistically.

Formations smaller than 30 mm (3 cm) are called nodules, while structures above this limit fall into the category of “mass” and carry a high suspicion of malignancy.

In terms of form; smooth, round and sharply circumscribed nodules usually come out benign; Spiculated, irregularly bordered and indented nodules are considered more risky for cancer.

Density of the Nodule (Ground Glass View)

“Ground-glass opacity”, which is frequently encountered in radiology reports, refers to a semi-transparent appearance in which lung tissue can still be seen through the nodule.

Unlike solid nodules, pure ground glass nodules grow more slowly but may be a precursor to an early-stage lung cancer (adenocarcinoma) in the long term.

Nodules, which we call part-solid, containing both ground glass and a hard core, are the group that should be followed most closely clinically.

Calcification (Calcification) Status

The appearance of calcification inside the nodule is a “benign” sign that is often in favor of the patient.

Dense calcifications, especially in the very center of the nodule or widespread, prove that this formation is a “petrified” scar due to a previous infection.

However, caution should be exercised in cases where calcification is pushed to the edges of the nodule or is irregular.

Lung Nodule Diagnosis and Diagnostic Methods

The diagnostic process follows a stepwise path to determine the character of the nodule and avoid unnecessary surgical intervention on the patient.

Computed Tomography (CT) and Follow-up Protocols

Low-dose computed tomography is the most basic tool in nodule monitoring.

The size and density of the nodule are compared in millimeters in tomography scans, which are usually taken every 3, 6 or 12 months.

If a nodule has not grown for 2 years, this is usually considered the strongest evidence that the nodule is benign.

The Role of PET-CT

PET-CT measures how quickly the radioactive sugar introduced into the body is consumed by the nodule (SUV value).

Since cancer cells consume much more energy (sugar) than normal cells, nodules with high involvement are prioritized for biopsy or surgery.

However, since the sensitivity of PET-CT decreases in nodules smaller than 8-10 mm, it is not always decisive in small nodules.

Bronchoscopic and Needle Biopsy

Depending on the location of the nodule, it may be necessary to take a tissue sample.

Biopsy is performed with a camera inserted through the mouth (bronchoscopy) for nodules close to the center of the lung, and with the help of a needle from the chest wall (TTIB) for nodules close to the outer parts.

However, in very small nodules, biopsy may not always give results; In this case, surgical removal of the nodule provides both diagnosis and treatment.

Prof. Dr. Levent Alpay: Especially in nodules under 1 cm, a “negative” biopsy result may not always mean that the nodule is benign; Sometimes the needle may not have hit the right cell. Therefore, radiological follow-up or direct surgical excision is a safer harbor in risky nodules.

Lung Nodule Treatment and Surgical Approaches

The treatment decision is made by calculating the risk of cancer of the nodule.

Follow-up (Wait and See) Process

The best treatment for low-risk, small and radiologically innocent-looking nodules is “patient follow-up”.

It is checked whether the nodule is asleep with intermittent tomography controls planned in a way that does not load the patient with unnecessary radiation.

Closed Lung Surgery (Nodule Removal with VATS)

If the nodule has suspicious features or has grown during follow-up, the nodule is removed by VATS (Video-Assisted Thoracoscopic Surgery) method.

In this closed method, the nodule is entered through small holes and removed with some healthy tissue around it (wedge resection).

Nodule Management Comparison Table

Status	Preferred Approach	Length of Hospital Stay
< 5 mm Innocent Nodule	Annual IT Follow-up	Not required
8-15 mm Suspicious Nodule	PET-CT or Follow-up Every 3 Months	Not required
Growing/Risky Nodule	Closed Surgery (VATS)	1 – 2 Days
Calcified (calcified) nodule	Usually no follow-up required	–

Surgical Intervention for Biopsy

In some cases, surgery is the shortest way to both make a definitive diagnosis (frozen examination) and complete the treatment in the same session if it is malignant.

The nodule removed during the operation is immediately sent to pathology; If the result is malignant, the surgeon can expand the operation and conclude the cancer treatment at that moment.

Frequently Asked Questions

Does Every Lung Nodule Turn Into Cancer?

No, the vast majority (more than 90%) of nodules detected in the lung are benign and can remain fixed throughout life without any harmful changes.

Is a 3 mm or 5 mm Lung Nodule Dangerous?

Nodules of this size are generally considered very low risk; However, if the patient has a history of heavy smoking or an existing cancer diagnosis, specialist follow-up should not be neglected.

Does a Nodule in the Lung Go Away on Its Own?

If the nodule is caused by an active infection or inflammation, it may shrink and disappear over time with the body’s healing process or appropriate treatment; however, calcified nodules are permanent.

You can make an appointment with our clinic and seek expert opinion to determine the character of a nodule detected in your lung and to create the most suitable follow-up or treatment roadmap for you.

Scientific Bibliography