800-258-1054

Stages of Lung Cancer

There are two primary types of lung cancer: non-small cell lung cancer (NSCLC) and small-cell lung cancer (SCLC). Since the management of cancer depends greatly on the extent of the disease—encapsulated tumor versus widespread metastatic disease, for example—oncologists have developed staging systems for virtually every type of cancer, including lung cancer. The behavior of NSCLC and SCLC in the body are quite different and are treated in very different ways, thus their staging systems are different.

Staging of Non-Small Cell Lung Cancer (NSCLC)

Cancer staging of non-small cell lung cancer NSCLC is based on a number of clinical findings, diagnostic studies, and laboratory findings. Since accurate staging in lung cancer is extremely important, particularly in NSCLC, once a diagnosis is made additional testing will be done to properly classify the tumor. Staging for lung cancer takes into consideration:

  • The patient’s medical, family, and social history
  • Findings on physical examination
  • Blood tests: Complete blood count (CBC), Serum electrolytes (CMP; Chem-10), Liver function tests (LFTs)
  • Radiological studies: Chest X-ray, Chest CT (possibly abdomen and pelvis also)

If the oncologist suspects a distant metastasis of the lung cancer based on history and physical exam, additional tests may be considered for the purposes of NSCLC staging. Positron emission tomography (PET) scanning is used to look for collections of cancerous cells throughout the body. Bone scintigraphy can be used if metastasis to bone is suspected and magnetic resonance imaging (MRI) is performed when the brain or spine are likely compromised by spread of the primary tumor.

Identifying the histological type of NSCLC tumor cell is important as well, which means that a pathological diagnosis is required. In order to obtain a pathological diagnosis, a biopsy of the tumor must be taken. This can be done through bronchoscopy, thoracosopy, fluoroscopic-guided biopsy, or open thoracotomy (rarely).

There are four stages in NSCLC, Stage I through Stage IV. Stages I, II, and III are further divided into A and B subtypes. Technically there is also a fifth stage, Stage 0, which is not an invasive cancer. These numbered stages are assigned based on a TNM staging system. TNM is an acronym that stands for Tumor, Node, and Metastasis. TNM staging is used to stage virtually every type of cancer; however, each TNM classification correlates to different stages across various types of cancer. In other words, Stage III lung and breast cancer may have different TNM stages.

Diagram of the lungs Once the size of the primary tumor is known, whether there are local/regional lymph nodes containing cancer cells, or if there are distant cancer cells (metastasis), the TNM classification is used to assign a stage based on the four-tiered scale.

 

Stages 0 to 4 of Lung Cancer
Stage TNM (Tumor, Nodes, Metastasis) Definition
Occult carcinoma TX, N0, M0 TX = Primary tumor cannot be assessed, or tumor proven by the presence of malignant cells in sputum or bronchial washings but not visualized by imaging or bronchoscopy.

N0 = No regional lymph node metastasis.

M0 = No distant metastasis.
0 Tis, N0, M0 Tis = Carcinoma in situ.

N0 = No regional lymph node metastasis.

M0 = No distant metastasis.
IA T1a, N0, M0

T1b, N0, M0
T1a = Tumor =2 cm in greatest dimension.

T1b = Tumor >2 cm but =3 in greatest dimension.

N0 = No regional lymph node metastasis.

M0 = No distant metastasis.
IB
T2a, N0, M0
T2a = Tumor >3 cm but =5 cm in greatest dimension.

N0 = No regional lymph node metastasis.

M0 = No distant metastasis.
IIA T1a, N1, M0

T1b, N1, M0

T2a, N1, M0

T2b, N0, M0
T1a = Tumor =2 cm in greatest dimension.

T1b = Tumor >2 cm but =3 cm in greatest dimension.

T2a = Tumor >3 cm but =5 cm in greatest dimension.

T2b = Tumor >5 cm but =7 cm in greatest dimension.

N0 = No regional lymph node metastasis.

N1 = Metastasis in ipsilateral peribronchial and/or ipsilateral hilar lymph nodes and intrapulmonary nodes, including involvement by direct extension.

M0 = No distant metastasis.
IIB T2b, N1, M0

T3, N0, M0
T2b = Tumor >5 cm but =7 cm in greatest dimension.

T3 = Tumor >7 cm or one that directly invades any of the following: parietal pleural (PL3) chest wall (including superior sulcus tumors), diaphragm, phrenic nerve, mediastinal pleura or parietal pericardium.

Tumor in the main bronchus (<2 cm distal to the carina, but without involvement of the carina.
Associated atelectasis or obstructive pneumonitis of the entire lung or separate tumor nodule(s) in the same lobe.

N0 = No regional lymph node metastasis.

N1 = Metastasis in ipsilateral peribronchial and/or ipsilateral hilar lymph nodes and intrapulmonary nodes, including involvement by direct extension.

M0 = No distant metastasis.
IIIA T1a, N2, M0

T1b, N2, M0

T2a, N2, M0

T2b, N2, M0

T3, N1, M0



T3, N2, M0


T4, N0, M0


T4, N1, M0
T1a = Tumor =2 cm in greatest dimension.

T1b = Tumor >2 cm but =3 cm in greatest dimension.

T2a = Tumor >3 cm but =5 cm in greatest dimension.

T2b = Tumor >5 cm but =7 cm in greatest dimension.

T3 = Tumor >7 cm or one that directly invades any of the following: parietal pleural (PL3) chest wall (including superior sulcus tumors), diaphragm, phrenic nerve, mediastinal pleura or parietal pericardium.

Tumor in the main bronchus (<2 cm distal to the carina but without involvement of the carina).

Associated atelectasis or obstructive pneumonitis of the entire lung or separate tumor nodule(s) in the same lobe.

T4 = Tumor of any size that invades any of the following: mediastinum, heart, great vessels, trachea, recurrent laryngeal nerve, esophagus, vertebral body, carina or separate tumor nodule(s) in a different ipsilateral lobe.

N0 = No regional lymph node metastasis.

N1 = Metastasis in ipsilateral peribronchial and/or ipsilateral hilar lymph nodes and intrapulmonary nodes, including involvement by direct extension.

N2 = Metastasis in ipsilateral mediastinal and/or subcarinal lymph node(s).

M0 = No distant metastasis.
IIIB T1a, N3, M0

T1b, N3, M0

T2a, N3, M0

T2b, N3, M0

T3, N3, M0



T4, N2, M0


T4, N3, M0
T1a = Tumor =2 cm in greatest dimension.

T1b = Tumor >2 cm but =3 cm in greatest dimension.

T2a = Tumor >3 cm but =5 cm in greatest dimension.

T2b = Tumor >5 cm but =7 cm in greatest dimension.

T3 = Tumor >7 cm or one that directly invades any of the following: parietal pleural (PL3) chest wall (including superior sulcus tumors), diaphragm, phrenic nerve, mediastinal pleura or parietal pericardium.

Tumor in the main bronchus (<2 cm distal to the carina but without involvement of the carina).

Associated atelectasis or obstructive pneumonitis of the entire lung or separate tumor nodule(s) in the same lobe.

T4 = Tumor of any size that invades any of the following: mediastinum, heart, great vessels, trachea, recurrent laryngeal nerve, esophagus, vertebral body, carina or separate tumor nodule(s) in a different ipsilateral lobe.

N2 = Metastasis in ipsilateral mediastinal and/or subcarinal lymph node(s).

N3 = Metastasis in contralateral mediastinal, contralateral hilar, ipsilateral or contralateral scalene or supraclavicular lymph node(s).

M0 = No distant metastasis.
IV Any T, any N, M1A



Any T, any N, M1b
TX = Primary tumor cannot be assessed, or tumor proven by the presence of malignant cells in sputum or bronchial washings but not visualized by imaging or bronchoscopy.

T0 = No evidence of primary tumor.

Tis = Carcinoma in situ.

T1 = Tumor =3 cm in greatest dimension, surrounded by lung or visceral pleura, without bronchoscopic evidence of invasion more proximal than the lobar bronchus (i.e., not in the main bronchus).

T1a = Tumor =2 cm in greatest dimension.

T1b = Tumor >2 cm but =3 cm in greatest dimension.

T2 = Tumor >3 cm but =7 cm or tumor with any of the following features (T2 tumors with these features are classified T2a if =5 cm): involves main bronchus, =2 distal to the carina, invades visceral pleura (PL1 or PL2) or is associated with atelectasis or obstructive pneumonitis that extends to the hilar region but does not involve the entire lung.

T2a = Tumor >3 cm but =5 cm in greatest dimension.

T2b = Tumor >5 cm but =7 cm in greatest dimension.

T3 = Tumor >7 cm or one that directly invades any of the following: parietal pleura (PL3) chest wall (including superior sulcus tumors), diaphragm, phrenic nerve, mediastinal pleura or parietal pericardium.

Tumor in the main bronchus (<2 cm distal to the carina but without involvement of the carina).

Associated atelectasis or obstructive pneumonitis of the entire lung or separate tumor nodule(s) in the same lobe.

T4 = Tumor of any size that invades any of the following: mediastinum, heart, great vessels, trachea, recurrent laryngeal nerve, esophagus, vertebral body, carina or
separate tumor nodule(s) in a different ipsilateral lobe.

NX = Regional lymph nodes cannot be assessed.

N0 = No regional lymph node metastasis.

N1 = Metastasis in ipsilateral peribronchial and/or ipsilateral hilar lymph nodes and intrapulmonary nodes, including involvement by direct extension.

N2 = Metastasis in ipsilateral mediastinal and/or subcarinal lymph node(s).

N3 = Metastasis in contralateral mediastinal, contralateral hilar, ipsilateral or contralateral scalene or supraclavicular lymph node(s).

M0 = No distant metastasis.

M1 = Distant metastasis.

M1a = Separate tumor nodule(s) in a contralateral lobe tumor with pleural nodules or malignant pleural (or pericardial) effusion.

M1b = Distant metastasis.

Treatment for NSCLC is based largely on the stage of the disease according to these four stages. While there are guidelines for what therapy should be used in a particular NSCLC stage, significant variability exists between oncologists since treatment is tailored to the needs and wishes of the patient. The table includes treatment for the first occurrence of NSCLC only (not recurrence). Also, if the lung cancer is causing significant, intractable pain or if the tumor is causing functional problems with other organs like the heart or brain, additional treatment may be used to reduce symptoms (rather than try for a cure). How the lung cancer was caused has no bearing on the staging or treatment.


Staging of Small Cell Lung Cancer (SCLC)

In contrast to non-small cell lung cancer (and most cancers), oncologists do not use the TNM staging system to classify small cell lung cancer (SCLC). The medical profession has found it is more useful to separate SCLC into two stages: limited stage and extensive stage. This does not mean that the staging workup is less involved; in fact, there may be more tests and studies done for the purpose of staging SCLC than NSCLC. The staging workup of SCLC involves:

  • Complete medical history
  • Complete physical examination
  • Blood tests
    • Complete blood count (CBC) with differential
    • Serum chemistry including blood urea nitrogen, creatinine, calcium, alkaline phosphatase (comprehensive metabolic panel)
    • Liver function tests
    • Serum lactate dehydrogenase
  • Chest X-ray
  • CT scan (computed tomography) of chest, abdomen and pelvis
  • MRI scan (magnetic resonance imaging) of brain (in most cases)
  • Bone scan
  • Bone marrow aspiration (if it will help direct treatment based on the rest of the workup)

There are some discrepancies and disagreements about what constitutes limited stage SCLC. Individual oncologists may have slightly different definitions regarding the precise scope of limited stage SCLC. The following are the consensus definitions.

Limited Stage

Limited stage disease is small cell lung cancer that is confined to one half of the chest, essentially. This can include any location within one lung, the entire mediastinum, and local lymph nodes. The National Cancer Institute defines local lymph nodes as those that can be reached with a single radiation that also treats the primary tumor. If cancer cell-containing lymph nodes are outside of the radiation port, the affected patient would warrant extensive stage status. A malignant pleural effusion qualifies as extensive stage.

Extensive Stage

Extensive stage small lung cancer is disease that cannot be included within or exceeds the limited stage criteria. It generally indicates cancer has spread to the opposite lung or to distant sites in the body. Metastatic lung cancer is a very challenging problem for the treating oncologist.

Treatment of lung cancer is based mostly on whether the cancer is limited or extensive stage. Small cell lung cancer tends to be very sensitive to radiation therapy, which means if it can be treated with a single radiation port, it should be tried. Generally radiation therapy is only used to treat limited stage SCLC. Surgery is rarely indicated in either limited or extensive stage SCLC. Chemotherapy is indicated in both SCLC stages, however the particular stage does guide which chemotherapeutic drugs should be used. Various chemotherapy regimens have been tried and continue to be used in SCLC. The major distinction is that sometimes only one drug can be used to treat limited stage disease when combined with radiation therapy while extensive stage disease is treated with more than one chemotherapeutic drug.

Compensation information is available for those diagnosed with lung cancer in our FREE Lung Cancer Information Packet or by calling toll-free 1-800-258-1054.

Read more about:
»
Lung Cancer Treatment
»How Lung Cancer Spreads