Lung Adenocarcinoma Stage III

Stage 3 lung adenocarcinoma is a form of lung cancer that has spread beyond the lung but has not yet reached distant organs. About one-third of people with lung cancer receive their diagnosis at this stage, when the disease is considered locally advanced and requires careful, coordinated treatment involving multiple approaches.

Table of contents

• What is Stage 3 Lung Adenocarcinoma
• Substages of Stage 3
• Symptoms and Warning Signs
• How Stage 3 is Diagnosed
• Treatment Options
• Outlook and Survival

What is Stage 3 Lung Adenocarcinoma

Stage 3 lung adenocarcinoma belongs to a larger group called non-small cell lung cancer, or NSCLC, which is the most common type of lung cancer^[1]. At stage 3, the cancer has begun to spread beyond the original location in the lung, but it has not yet traveled to distant parts of the body^[3].

Stage 3 is sometimes called locally advanced cancer. The disease has not spread outside the chest area, but it may have grown into nearby structures or reached lymph nodes in the chest^[1]. Around 30% of people with non-small cell lung cancer are diagnosed at stage 3^[4].

In stage 3 lung cancer, tumors may be found in several locations. The cancer can affect the lungs themselves, the main airways called bronchi, nerves, blood vessels, the chest wall, or other organs in the chest^[4]. It may also have spread to lymph nodes, which are small glands that help the body fight infection^[6].

Substages of Stage 3

Stage 3 non-small cell lung cancer is divided into three substages: 3A, 3B, and 3C. These divisions are based on the size of the tumor, where it is located, and whether it has spread to lymph nodes^[4].

Stage 3A means the cancer is between 3 and 7 centimeters in size. The cancer may have spread to lymph nodes on the same side of the chest where the tumor started^[4]. Stage 3A can also include smaller tumors that have grown into certain structures near the lung, such as the membrane covering the lung or the chest wall, but have not yet spread to lymph nodes^[1].

Stage 3B cancer may have grown larger and spread to lymph nodes on either side of the chest, in the neck, or above the collarbone^[4]. At this stage, the cancer has not spread to distant organs, but it has reached lymph nodes farther from the original tumor^[1].

Stage 3C is the most advanced substage within stage 3. The cancer has spread to lymph nodes on the opposite side of the chest from where it started, or to lymph nodes on either side of the neck or above the collarbone^[4]. The cancer may also have grown into the chest wall, heart, breastbone, and other nearby tissues^[7].

Symptoms and Warning Signs

Many people with non-small cell lung cancer do not notice symptoms in the early stages, which is one reason why the disease is often diagnosed at a more advanced stage^[7]. However, as the cancer grows, several symptoms may appear.

The most common symptom is a cough that does not go away. Other respiratory symptoms include shortness of breath or wheezing^[7]. Some people may cough up blood or rust-colored mucus^[7].

Chest pain is another frequent symptom. People may also experience unexplained weight loss or feel more tired than usual^[7]. Changes in voice, such as hoarseness, can occur if the cancer affects the nerves that control the voice box^[7].

If stage 3 lung cancer has spread to other structures in the chest, it can cause additional symptoms. For example, if the cancer reaches the bones, it may cause bone pain^[7].

How Stage 3 is Diagnosed

Doctors use several tests to diagnose and determine the stage of lung cancer. The process usually begins when a person develops symptoms and visits a doctor. Most people are not routinely checked for lung cancer unless they smoke or have other risk factors^[7].

A chest X-ray is often the first imaging test performed. If the X-ray suggests cancer, the doctor will order additional tests^[7]. A CT scan, or computed tomography scan, creates detailed 3D images of the inside of the body and can show the size and location of tumors^[7].

Doctors use a staging system called TNM to classify lung cancer. TNM stands for Tumor, Node, and Metastasis. The system looks at the size and location of the tumor, whether cancer has spread to lymph nodes, and how far the cancer has spread from its original location^[7].

To confirm the diagnosis, doctors often perform a biopsy, which involves taking a small sample of tissue to examine under a microscope. Additional tests may be done to identify specific characteristics of the cancer cells, which can help guide treatment decisions^[7].

Treatment Options

Treatment for stage 3 lung adenocarcinoma typically involves a combination of therapies. The specific plan depends on factors such as the exact substage of the cancer, the patient’s overall health, and whether the tumor can be removed with surgery^[3].

The majority of stage 3 lung cancer is considered unresectable, meaning it cannot be removed with surgery because of where it has spread^[4]. For patients with unresectable stage 3 disease, treatment often involves a combination of chemotherapy and radiation therapy given at the same time, known as chemoradiation^[11].

Chemotherapy uses drugs to kill cancer cells or stop them from growing. Common chemotherapy combinations include cisplatin with other drugs such as etoposide, vinorelbine, or gemcitabine^[11]. Radiation therapy uses high-energy rays to destroy cancer cells^[11].

For some patients with stage 3A disease, surgery may be an option after chemoradiation has shrunk the tumor. Types of surgery include lobectomy, which removes one lobe of the lung, or pneumonectomy, which removes the entire lung^[11]. For stage 3B and 3C disease, surgery is generally not recommended^[11].

Recent advances have brought new treatment options. Immunotherapy helps the body’s immune system fight cancer. It may be given after chemoradiation for patients whose cancer has responded to treatment or remained stable^[4]. Targeted therapy uses drugs that attack specific characteristics of cancer cells. The type of targeted therapy depends on specific genetic changes found in the tumor^[11].

One targeted therapy approach focuses on a protein called EGFR (epidermal growth factor receptor), which sits on the surface of cells and helps them grow and divide. If the cancer has a mutation in the EGFR gene, certain drugs can block this protein and slow cancer growth^[11].

The goal of treatment is to control the cancer, extend life, and improve quality of life. Treatment decisions are best made by a multidisciplinary team of doctors working together, and should be discussed carefully with each patient^[5].

Outlook and Survival

A person’s outlook with stage 3 lung cancer depends on many factors, including their age, overall health, the specific characteristics of the cancer, and how well it responds to treatment^[3].

According to statistics from England covering diagnoses from 2016 to 2020, around 15 out of 100 people (around 15%) with stage 3 lung cancer survive for 5 years or more after diagnosis^[19]. These figures represent averages for large groups of people and cannot predict what will happen in any individual case^[19].

It is important to remember that survival statistics are based on people diagnosed and treated several years ago. Treatments have improved significantly in recent years, particularly with the introduction of immunotherapy and targeted therapies^[5]. Some patients treated with modern approaches may have better outcomes than these statistics suggest.

Stage 3 lung cancer is harder to treat than earlier stages, but some patients can achieve long-term survival with aggressive treatment^[6]. While there is currently no cure for stage 3 lung cancer, treatments can help extend life and reduce symptoms^[3].