Lung Cancer: Types & Stages
At Mat-Su Valley Comprehensive Cancer Center, our cancer experts strive to make sure you understand both your diagnosis and the many different treatment options available to you. Based on your type of cancer, along with other factors such as the stage of your cancer, your age, overall health, and personal preferences, our board-certified radiation oncologists in Palmer will consult with the other members of your medical team to develop the best treatment plan for you.
Types Of Lung Cancer
Each type of lung cancer is treated differently, so it is very important to determine which type you have before evaluating treatment options. Your doctor will assess your lung cancer type i two ways: looking at the cells under a microscope, and discovering your molecular profile or the types of biomarkers found in the tissue. There are three broad categories of lung cancer that are described by the types of cells that the doctor sees under the microscope.
- Non-Small Cell Lung Cancer (NSCLC) – By far the most common type of lung cancer, about 85% of diagnosed lung cancer is attributed to this type. NSCLC usually grows and spreads at a slower rate than other types of cancer. Some tumors are made up of cells from more than one type of NSCLC, but the most commonly diagnosed types of NSCLC are:
- Adenocarcinoma – Lung adenocarcinoma accounts for about 40% of all lung cancers. This type of cancer has gland-like properties and begins in early versions of the cells that make up the lining of the lungs. Glandular cells are found in the lungs and some other internal organs. Most cancers of the breast, pancreas, prostate, and colon are also adenocarcinomas. Only adenocarcinoma that begins in the lungs is considered lung cancer. It is the most common form of cancer for both men and women in the U.S. It occurs most often in smokers or former smokers, but it is also the most common type of cancer in nonsmokers and younger people. One type of adenocarcinoma, called adenocarcinoma in situ, is more treatable than the others.
- Squamous Cell Carcinoma – These abnormal cells can usually be found near a main airway toward the central part of the lungs. Squamous cell lung cancer accounts for about 30% of all lung cancers. There are numerous treatment options available to people diagnosed with squamous cell lung cancer, and doctors are working hard to develop and improve these treatments.
- Large Cell Carcinoma – This is a faster-growing form of NSCLC that can appear on any part of the lung and does not fit into the other categories. In the past, about 10% of all lung cancers were classified as large cell. However, as more exact ways of diagnosing lung cancer have come into use, this percentage is dropping. Many lung cancers that would have been considered large cell in the past are now being identified as adenocarcinoma or squamous cell lung cancer. Having this additional information is important for choosing treatment options. The majority of large cell lung cancers are found in men.
- Large Cell Neuroendocrine Tumors – These fast-growing tumors make up only about 2% of lung cancer diagnoses.
- Small Cell Lung Cancer (SCLC) – These much faster growing and spreading cancer cells look flat and smaller than normal, healthy cells. Resembling tiny oats under a microscope, it is also called “oat cell” cancer. The cells in this neuroendocrine tumor are smaller in size than most other cancer cells. Small cell lung cancer (SCLC) accounts for about 15% of all lung cancers in the U.S. and is usually caused by smoking tobacco. Chemotherapy is often the best treatment for this type of cancer, but advanced radiation treatments are providing favorable outcomes. In addition to existing treatment approaches, several promising new treatment approaches are being developed.
- Metastatic Lung Cancer – Any cancer which originated in the lungs, but the spreads through your blood or lymph nodes to other parts of your body is considered metastatic lung cancer. It is treated as lung cancer based on the type of lung cancer that it is. This can happen before or after treatment.This is different than recurrent cancer because it spreads to a different part of the body than was previously infected.
Non-Small Cell Lung Cancer (NSCLC) Stages
Doctors developed a rating system for cancer in order to help discuss and design treatment options and predict your prognosis. They use diagnostic tests to find out the cancer’s stage based on where the cancer is located, if or where it has spread and whether it’s affecting other parts of the body. One of the ways doctors decide on the stage is to find out if the cancer can be completely removed by a surgeon. Cancer stages are usually described in roman numerals.
You may also hear about the TNM classification, because the stages below have been developed based on a combination of:
- T: The size of the primary tumor
- N: Whether and how regional lymph nodes are affected by the cancer
- M: Whether there is distant metastasis
Doctors assign levels for each of the above factors and then combine these levels into stages. They stages of lung cancer are:
- Stage 0 – This is a non-invasive cancer when the disease is very small, remains in place (in situ), and has not spread into deeper lung tissue or to other surrounding tissue.
- Stage I – A lung cancer that includes a small tumor that might have spread into the underlying lung tissue, but that has not spread to any lymph nodes in other parts of the body. The surgeon is able to remove the tumor.
- Stage Ia – The tumor is smaller than 3 cm. wide.
- Stage Ib – The tumor is between 3 cm. and 5 cm. wide.
- Stage II – There are two substages of Stage II cancer. A surgeon may or may not be able to remove the entire tumor.
- Stage IIa – In this stage, the tumor is between 5 cm. and 7 cm. wide and has not spread to nearby lymph nodes; OR the tumor is less than 5 cm. and HAS spread to nearby lymph nodes.
- Stage IIb – If the tumor is between the 5 cm. and 7 cm. as in the earlier stage, but it HAS spread to nearby lymph nodes, it is considered Stage IIb. Or, if the tumor is larger than 7 cm. wide but has not spread, it falls into this stage. The tumor may also be partly blocking the airways.
- Stage III – Stage IIIa lung cancers and almost all of stage IIIb cancers include a tumor that is difficult, sometimes impossible, to remove. The lung cancer may have spread into the lymph nodes in the center of the chest, but outside the lung. Or, the tumor might have grown into nearby structures in the lung. It is less likely, in these cases, that the surgeon can completely remove the cancer because it has to be taken out piece by piece.
- Stage IV – Surgery is not usually successful for most Stage III or Stage IV lung cancers. If the cancerous cells have become Stage IV and have spread to lymph nodes above the collarbone or if the cancer has grown into fluid surrounding the lung, or vital structures within the chest like the heart, large blood vessels, or primary airways, it can be impossible to remove. If the cancer spreads to the blood, it can easily travel to the brain, bones, liver, and adrenal glands.
- Stage IVa – Cancer has spread within the chest.
- Stage IVb – Cancer has spread outside the chest to other parts of the body.
- Recurrent – This stage of cancer is used when the cancer returns to the originally infected place after treatment. Once that happens, doctors run more tests to establish a current stage.
Stages Of Small Cell Lung Cancer (SCLC)
- Limited stage: There are cancerous cells found on just one side of the chest, affecting only one part of the lung and nearby lymph nodes.
- Extensive stage: Cancer has spread to other areas of the chest or other parts of the body.
- Lung Cancer – About Lung Cancer
- Lung Cancer – Detection and Treatment Options
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