TürkçeLung cancer diagnosis is performed through the systematic use of advanced imaging and interventional methods such as low-dose computed tomography (LDCT), PET-CT, bronchoscopy, and endobronchial ultrasonography (EBUS). The process begins with the radiological detection of suspicious lung lesions and is confirmed pathologically through tissue sampling techniques. These examinations determine the anatomical extent of the disease, enabling thoracic surgeons to rapidly establish the most appropriate treatment strategy. Thanks to modern medical technologies, suspicious findings detected at an early stage can be successfully managed with curative surgical intervention. Rapid and accurate diagnosis is the most critical stage directly affecting survival rates.
What Is Lung Cancer and Into Which Subgroups Is It Classified According to Cell Type?
The microscopic structure and behavior of the cells largely determine the course of the disease and the treatment to be applied. According to medical pathology examinations, this disease is generally divided into two main groups. These main groups and their subtypes are as follows:
- Small cell lung cancer
- Non-small cell lung cancer
- Squamous cell carcinoma
- Adenocarcinoma
- Large cell carcinoma
The small cell type listed above takes its name from the characteristically small and round appearance of the cells under the microscope. It generally has a tendency to grow rapidly. It has a very strong association with tobacco use. Rather than surgery, it is generally a type with a high potential to respond to drug treatments such as chemotherapy.
The non-small cell type constitutes the vast majority of the cases we encounter. It is the group in which surgical intervention is most frequently considered when detected early. One of its subtypes, squamous cell carcinoma, often begins in the main airways at the center of the lung. Adenocarcinoma, on the other hand, usually develops in mucus-producing cells located in the outer parts of the lung and, interestingly, is encountered relatively more frequently in individuals who have never used tobacco products throughout their lives or in women. As its name suggests, the large cell type consists of larger cells and may tend to progress somewhat faster than the others.
What Are the Main Risk Factors Involved in the Development of Lung Cancer?
Many different environmental, hereditary, and lifestyle-related factors play a role in the development of the disease. The main factors are as follows:
- Tobacco and tobacco products
- Asbestos fibers
- Radon gas
- Genetic factors
- Environmental pollution
Tobacco use is the most common and well-known factor involved in the development of the disease. It is sometimes believed that products with lower tar or lower nicotine levels may be safer; however, medical evidence does not indicate that such products significantly reduce the risk. On the contrary, individuals may inhale smoke much more deeply in an attempt to reach the nicotine level to which their bodies have become accustomed, exposing the farthest regions of the lungs to intense chemicals. Asbestos is a mineral found especially in insulation materials, shipbuilding, and old construction materials, and prolonged inhalation of its fibers may disrupt cellular structure. Radon gas, which forms naturally in the soil and can seep into buildings from underground, also poses a long-term risk. In addition, having a family history of similar health problems may indicate a genetic predisposition.
What Symptoms Indicate Early-Stage or Advanced Lung Cancer?
The internal structure of the lungs does not contain a dense network of nerves that transmit pain sensations. Therefore, symptoms of the disease may sometimes appear quite late. The most common warning signals given by the body are:
- Chronic cough
- Bloody sputum
- Shortness of breath
- Wheezing
- Chest pain
- Shoulder pain
- Hoarseness
- Loss of appetite
- Weight loss
The mechanism behind these symptoms is quite logical. A persistent cough that gradually changes in character generally begins due to narrowing of the airways or disruption of the lung’s natural cleansing system. The presence of blood in the sputum is a very important warning sign resulting from damage to newly formed and fragile blood vessels in the region and should always be taken seriously.
Shortness of breath and wheezing occur due to obstruction of the air passages. Pain usually becomes apparent when the lesion begins to involve the pleura, chest wall, or nerves surrounding the ribs. This pain may be felt as a stabbing sensation during deep breathing or while laughing. Compression of the nerve that travels through the chest cavity to the vocal cords may cause the voice to become hoarse. In addition, changes in the body’s energy balance and certain chemicals released into the body may lead to unexplained fatigue and rapid weight loss.
What Is a Solitary Pulmonary Nodule and How Is It Evaluated in Terms of Lung Cancer?
We frequently encounter small spots that are incidentally detected on X-rays or CT scans performed for a different health problem. We refer to these round lesions, which are surrounded by normal lung tissue, measure less than three centimeters in diameter, and are not associated with fluid accumulation, as solitary pulmonary nodules.
The most delicate aspect here is to avoid causing unnecessary stress for the patient because of a benign nodule that will not cause harm while at the same time recognizing a potentially risky lesion in a timely manner. A large proportion of very small, millimetric nodules may simply represent insignificant scar tissue left behind by a previous mild lung infection.
How Is the Probability That a Suspicious Nodule Is Lung Cancer Calculated?
When evaluating the characteristics of a lesion, attention is focused on its size, whether its borders are smooth, the pattern of calcification within it, and its growth rate. The time required for the nodule to double in volume provides highly valuable information during follow-up.
In this calculation, the letter t represents the number of days between the two imaging studies, d1 represents the initial size, and d2 represents the most recently measured size. If a nodule doubles in size in less than twenty days, this generally suggests an acute inflammatory process. Lesions that remain unchanged in size for more than four hundred fifty days indicate a high probability of being benign. Some imaging features that are considered during risk assessment include:
- Nodule diameter
- Irregular borders
- Spiculated extensions
- Eccentric calcification
- Ground-glass appearance
- Satellite nodules
Nodules with irregular borders and star-like outward extensions require closer evaluation. While complete and regular calcification in the center of the nodule generally suggests a benign lesion, irregular calcifications distributed along the edges or lesions with a ground-glass appearance may require more careful follow-up and further investigation.
What Imaging Methods Are Used for Lung Cancer Diagnosis?
Various advanced imaging modalities are used to confirm the presence of the disease and clearly determine its location within the body. The most commonly used methods during this process are:
- Low-dose computed tomography
- Computed tomography
- Positron emission tomography
- Magnetic resonance imaging
- Bone scintigraphy
Computed tomography provides a detailed, millimetric map of the tissues, allowing us to understand anatomical relationships. Positron emission tomography, commonly known as a PET scan, demonstrates how cells utilize a very small amount of radioactively labeled glucose administered intravenously. Cells with high energy consumption absorb more of this glucose and appear brighter on the images, providing valuable information about the biological activity of the area. Magnetic resonance imaging is generally preferred for evaluating regions such as the spine or brain, while bone scintigraphy is used to assess the skeletal system.
Which Invasive Methods Are Used for the Diagnosis of Lung Cancer?
Following imaging studies, tissue or cell samples must be obtained from the suspicious area to establish a definitive diagnosis. Depending on the patient’s condition and the location of the lesion, various minimally invasive procedures may be performed. Commonly used methods include:
- Bronchoscopy
- Endobronchial ultrasonography
- Transbronchial needle aspiration
- Mediastinoscopy
- Chamberlain procedure
- Video-assisted lymphadenectomy
Bronchoscopy is the examination of the airways from the inside using a flexible, thin tube equipped with a light source and camera. This allows changes within the airways to be observed directly, and tissue samples can be collected using small brushes or forceps. Endobronchial ultrasonography is a modified version of this procedure in which a miniature ultrasound device is attached to the tip of the bronchoscope. It detects lymph nodes located outside the airways, areas that cannot normally be seen directly, using sound waves and enables fluid samples to be obtained from these nodes with a specialized needle.
If these methods cannot reach the target area or if a larger tissue sample is required, thoracic surgeons may perform different procedures. Mediastinoscopy involves accessing the central chest cavity through a very small incision just below the neck under general anesthesia to examine the lymph nodes located there. The Chamberlain procedure is generally a different surgical approach performed through the ribs for lesions located on the left side. Video-assisted lymphadenectomy allows a broader and more detailed analysis of lymphatic tissues using cameras. The purpose of these procedures is to understand the relationship between the tumor and the surrounding tissues and to establish a solid foundation for the main treatment to be applied.
What Minimally Invasive Surgical (VATS) Methods Are Used in Lung Cancer Operations?
In the past, lung surgeries were performed through open surgical procedures (thoracotomy), in which the ribs were widely separated. Today, however, with advances in medicine, minimally invasive surgical techniques using cameras and specialized instruments, known as Video-Assisted Thoracic Surgery (VATS), have come to the forefront. The commonly used techniques are:
- Standard thoracoscopy
- Single-port thoracoscopy
- Robotic surgery
In the standard minimally invasive approach, two or three small access ports are generally created in the chest wall. The surgeon performs the operation using delicate instruments while viewing the images transmitted by the high-resolution camera on a large monitor.
The single-port, also known as the uniportal approach, is generally performed through a single incision measuring only a few centimeters, usually made in the underarm region. Both the camera and all surgical instruments are inserted through this small opening. Because there is minimal disruption to the muscles and nerves, the patient’s recovery and return to daily life after surgery are generally very rapid.
In robotic surgery, the robotic arms are designed to have a high degree of mobility similar to the human hand. The surgeon performs the operation from a console in the operating room rather than standing beside the patient, using three or four small access ports while viewing highly magnified three-dimensional images.
Minimally invasive surgical techniques are widely preferred not only to remove cancerous tissue but also for diagnostic purposes, such as obtaining a small sample from a nodule with an uncertain diagnosis or draining fluid accumulated in the pleural cavity.
How Is Lung Cancer Treatment Planned According to Its Stage?
Staging systems are used to describe the extent of the disease in a standardized manner. This assessment considers the size of the tumor, whether it has spread to nearby lymph nodes, and whether it has metastasized to other parts of the body. The treatment plan is also shaped by taking into account the patient’s overall health, age, and accompanying medical conditions. The stages of the disease are generally as follows:
- Stage I
- Stage II
- Stage III
- Stage IV
In Stage I, the tumor is relatively small and has not spread to nearby lymph nodes. For patients diagnosed at this stage, the primary and most important treatment option is generally surgical removal of the affected area. Minimally invasive surgical techniques offer significant advantages for patients in this group.
In Stage II, the tumor may have increased in size or spread slightly to nearby airway lymph nodes. Surgery is generally still the primary approach, and adjuvant drug therapies may be planned after surgery to further reduce the risk of recurrence.
Stage III is the period during which the disease has spread more extensively to the lymph nodes within the chest cavity. Decisions at this stage are generally made by multidisciplinary teams consisting of thoracic surgeons, medical oncologists, and radiation oncologists. In some cases, the goal is to shrink the disease with drug therapy first and then perform surgery if appropriate.
In Stage IV, the disease has spread through the bloodstream to distant organs such as the bones, brain, or liver. At this stage, the primary objective is not surgery but rather minimizing symptoms and maintaining quality of life through modern targeted therapies, immunotherapies, and radiotherapy.
How Does the Referral Process Work for Patients with Suspected Lung Cancer?
When a suspicious radiological finding involving the lung or a persistent cough is identified, one of the most critical steps is for the patient to consult an experienced thoracic surgery and pulmonology team without delay. In centers equipped with appropriate technical resources and expertise, diagnostic and treatment steps can be carried out rapidly and in a coordinated manner.
In our country, there are also highly experienced centers that closely follow international developments in this field. For example, at the Thoracic Surgery Department of Acıbadem Maslak Hospital, Prof. Dr. Semih Halezeroğlu and his team provide patients with support in minimally invasive surgical techniques and advanced diagnostic methods.
Suspicion of the disease or a newly established diagnosis is often confusing for both patients and their families. During such periods, patients may wish to seek a second medical opinion to better understand their condition, confirm the suitability of the proposed treatment, or gain a different perspective. Thanks to today’s digital opportunities, initiating this process has become much easier. The communication steps generally followed within online consultation services include:
- Submitting an information request
- Sending medical records
- Preliminary review of reports
- Conducting a video consultation
Patients can contact the clinic through digital messaging platforms or by telephone. Their CT scan CDs, pathology reports, and blood test results can be securely transferred electronically to the clinic. After these records are thoroughly reviewed by specialist physicians, an online video consultation is arranged with the patient and family members. During this meeting, the current condition is explained clearly and transparently in language that the patient can easily understand. If additional examinations are required, they are planned. If minimally invasive surgery is a possibility, its details are discussed. As a result, the patient gains a clear roadmap regarding the next steps to be taken.
Frequently Asked Questions
Prof. Dr. Alper Fındıkcıoğlu graduated from Istanbul University Faculty of Medicine and completed his thoracic surgery residency at Dr. Siyami Ersek Hospital. He began his academic career at Başkent University in 2005; he received the title of associate professor in 2014 and professor in 2022. He has extensive experience in lung cancer, chest wall diseases, and minimally invasive surgery. Since 2024, he has been continuing his professional work at Acıbadem Hospital.
