Non-Small Cell Lung Cancer Stage IIIB

Stage IIIB non-small cell lung cancer represents an advanced form of the disease where cancer has spread beyond the lung to nearby structures and lymph nodes, yet has not reached distant organs. Understanding this stage and the available treatment options is essential for making informed decisions about care.

Table of contents

• What is Stage IIIB Non-Small Cell Lung Cancer?
• How Stage IIIB is Classified
• Diagnosis and Detection
• Treatment Approaches
• Outlook and Survival

What is Stage IIIB Non-Small Cell Lung Cancer?

Non-small cell lung cancer (NSCLC) is the most common type of lung cancer, accounting for about 85% of all lung cancer cases^[4][7]. When doctors diagnose stage IIIB NSCLC, this means the cancer has grown and spread in ways that make it more advanced than earlier stages, but it has not yet spread to distant parts of the body.

In stage IIIB, the cancer has typically grown larger and spread to lymph nodes on either side of the chest, the neck, or above the collarbone^[4][6]. Approximately 30% of people with NSCLC are diagnosed at stage 3^[4], and about 20-35% of NSCLC diagnoses fall specifically into stage III disease^[5][20].

Stage IIIB is sometimes called locally advanced cancer because the disease has spread within the chest region but not to other organs like the bones or liver^[7]. The majority of stage IIIB cancers are considered unresectable, meaning they cannot be removed with surgery^[4].

How Stage IIIB is Classified

Doctors use a system called TNM staging to classify lung cancer. This system examines three key factors: the tumor size and location (T), whether cancer has spread to lymph nodes (N), and whether it has spread to distant organs, called metastasis (M)^[3][20].

There are four possible ways a cancer can be classified as stage IIIB. In all cases, the cancer has not spread to distant parts of the body. Stage IIIB can mean the cancer is 3 centimeters or smaller and has spread to lymph nodes in the space between the lungs on the opposite side from where the cancer started, lymph nodes at the base of the neck, or lymph nodes above the collarbone on either side^[6].

Stage IIIB can also describe cancers between 3 and 5 centimeters with similar patterns of lymph node involvement. In some cases, the tumor may have grown into the main airway of the lung, the membrane covering the lung, or caused the lung to partially or completely collapse^[6].

The cancer may also be larger than 5 centimeters or may have grown into structures in the chest such as the chest wall, the muscle below the lung called the diaphragm, the area between the lungs, the heart, major blood vessels, the windpipe, the food pipe, or bones of the spine^[6]. Stage IIIB differs from stage IIIA and IIIC based on the specific combination of tumor size, location, and extent of lymph node involvement.

Diagnosis and Detection

Most people with stage IIIB lung cancer experience symptoms because of how the disease has progressed. Common symptoms include a persistent cough that does not go away, chest pain, shortness of breath, coughing up blood or rust-colored sputum, hoarse voice, weight loss, and extreme tiredness^[7][9].

If lung cancer is suspected, doctors use several types of tests to diagnose and stage the disease. A chest X-ray is often the first imaging test performed^[7]. If the X-ray suggests cancer, additional scans are ordered, including computed tomography (CT) scans, positron emission tomography (PET) scans, and magnetic resonance imaging (MRI)^[7].

To confirm the diagnosis, doctors perform a biopsy, which involves examining a sample of tissue under a microscope^[7]. Various procedures can be used to obtain tissue samples, including bronchoscopy (using a lighted tube inserted through the throat), needle biopsy, or surgical procedures.

Tests to check if cancer has spread to the chest include endobronchial ultrasound (using sound waves to create images), mediastinoscopy (inserting an instrument through a small cut to examine the space between the lungs), and other specialized procedures^[7].

Treatment Approaches

Treatment for stage IIIB NSCLC is complex and requires careful planning by a team of specialists. Because most stage IIIB cancers cannot be removed with surgery, the main treatment approaches involve combinations of different therapies^[10][14].

Chemoradiation therapy, which combines chemotherapy with radiation therapy given at the same time, is a standard treatment for patients who are well enough to receive it^[14]. The chemotherapy drugs most commonly used include cisplatin combined with etoposide^[14]. Other drug combinations may include cisplatin or carboplatin with vinorelbine, gemcitabine, docetaxel, paclitaxel, or pemetrexed^[14].

For patients who are not well enough for combined chemoradiation, chemotherapy alone may be offered^[14]. In rare cases where chemoradiation successfully shrinks the tumor significantly, surgery might be considered^[14].

In recent years, immunotherapy has become an important treatment option. After completing chemoradiation, some patients may receive immunotherapy drugs that help the immune system fight cancer. These drugs, called immune checkpoint inhibitors, work by allowing the body’s immune system to attack cancer cells more effectively^[4][5].

Targeted therapy may also be an option for some patients. These treatments work against specific genetic changes found in the cancer cells. The type of targeted therapy used depends on the specific genetic mutations present in the tumor^[14]. Common targets include changes in genes called EGFR (epidermal growth factor receptor), ALK, ROS1, BRAF, and others^[14].

Treatment decisions depend on several factors including the patient’s overall health, the exact characteristics of the cancer, and whether specific genetic changes are found in the tumor. The goal is to control the cancer, relieve symptoms, and improve quality of life.

Outlook and Survival

Stage IIIB non-small cell lung cancer is considered advanced, and treatment aims to control the disease and improve survival. While this stage presents significant challenges, advances in treatment, particularly the addition of immunotherapy and targeted therapies, have improved outcomes for many patients^[5][12].

The outlook varies considerably based on individual factors such as overall health, response to treatment, specific characteristics of the cancer, and the presence of targetable genetic changes. Some patients with stage 3 NSCLC can achieve long-term survival with aggressive treatment^[17].

Because stage IIIB is locally advanced but has not spread to distant organs, patients may benefit from treatments that work to control the cancer in the chest region. The management of stage III NSCLC requires discussion in multidisciplinary teams to determine the best approach for each individual patient^[5][12].

Palliative care, which focuses on relieving symptoms and improving quality of life, is an important part of treatment for stage IIIB lung cancer. Research has shown that patients who receive palliative care early in their treatment often have better quality of life^[16].