Lung Cancer Part-8

Lung Cancer Part-8

What is the prognosis (outcome) of lung cancer?

The prognosis of lung cancer refers to the chance for cure or prolongation of life (survival) and is dependent upon where the cancer is located, the size of the cancer, the presence of symptoms, the type of lung cancer, and the overall health status of the patient.
SCLC has the most aggressive growth of all lung cancers, with a median survival time of only 2 to 4 months after diagnosis when untreated. (That is, by 2 to 4 months, half of all patients have died.) However, SCLC is also the type of lung cancer most responsive to radiation therapy and chemotherapy. Because SCLC spreads rapidly and is usually disseminated at the time of diagnosis, methods such as surgical removal or localized radiation therapy are less effective in treating this type of lung cancer. When chemotherapy is used alone or in combination with other methods, survival time can be prolonged four- to fivefold; however, of all patients with SCLC, only 5% to 10% are still alive 5 years after diagnosis. Most of those who survive have limited-stage SCLC.
In non-small cell lung cancer (NSCLC), the most important prognostic factor is the stage (extent of spread) of the tumor at the time of diagnosis. Results of standard treatment are generally poor in all but the smallest of cancers that can be surgically removed. However, in stage I cancers that can be completely removed surgically, 5-year survival approaches 75%. Radiation therapy can produce a cure in a small minority of patients with NSCLC and leads to relief of symptoms in most patients. In advanced-stage disease, chemotherapy offers modest improvements in survival although rates of overall survival are poor.

The overall prognosis for lung cancer is poor when compared with some other cancers. Survival rates for lung cancer are generally lower than those for most cancers, with an overall 5-year survival rate for lung cancer of about 17% compared to 67% for colon cancer, 90% for breast cancer, 81% for bladder cancer, and over 99% for prostate cancer.

Lung Cancer Part-7

Lung Cancer Part-7

What is staging of lung cancer?

The stage of a cancer is a measure of the extent to which a cancer has spread in the body. Staging involves evaluation of a cancer's size and its penetration into surrounding tissue as well as the presence or absence of metastases in the lymph nodes or other organs. Staging is important for determining how a particular cancer should be treated, since lung-cancer therapies are geared toward specific stages. Staging of a cancer also is critical in estimating the prognosis of a given patient, with higher-stage cancers generally having a worse prognosis than lower-stage cancers.
Doctors may use several tests to accurately stage a lung cancer, including laboratory (blood chemistry) tests, X-rays, CT scans, bone scans, MRI scans, and PET scans. Abnormal blood chemistry tests may signal the presence of metastases in bone or liver, and radiological procedures can document the size of a cancer as well as its spread.
NSCLC are assigned a stage from I to IV in order of severity:

• In stage I, the cancer is confined to the lung.
• In stages II and III, the cancer is confined to the chest (with larger and more invasive tumors classified as stage III).
• Stage IV cancer has spread from the chest to other parts of the body.

SCLC are staged using a two-tiered system:

• Limited-stage (LS) SCLC refers to cancer that is confined to its area of origin in the chest.
• In extensive-stage (ES) SCLC, the cancer has spread beyond the chest to other parts of the body.

What is the treatment for lung cancer?

Treatment for lung cancer can involve surgical removal of the cancer, chemotherapy, or radiation therapy, as well as combinations of these treatments. The decision about which treatments will be appropriate for a given individual must take into account the location and extent of the tumor as well as the overall health status of the patient.
As with other cancers, therapy may be prescribed that is intended to be curative (removal or eradication of a cancer) or palliative (measures that are unable to cure a cancer but can reduce pain and suffering). More than one type of therapy may be prescribed. In such cases, the therapy that is added to enhance the effects of the primary therapy is referred to as adjuvant therapy. An example of adjuvant therapy is chemotherapy or radiotherapy administered after surgical removal of a tumor in an attempt to kill any tumor cells that remain following surgery.

Surgery: Surgical removal of the tumor is generally performed for limited-stage (stage I or sometimes stage II) NSCLC and is the treatment of choice for cancer that has not spread beyond the lung. About 10% to 35% of lung cancers can be removed surgically, but removal does not always result in a cure, since the tumors may already have spread and can recur at a later time. Among people who have an isolated, slow-growing lung cancer removed, 25% to 40% are still alive 5 years after diagnosis. It is important to note that although a tumor may be anatomically suitable for resection, surgery may not be possible if the person has other serious conditions (such as severe heart or lung disease) that would limit their ability to survive an operation. Surgery is less often performed with SCLC than with NSCLC because these tumors are less likely to be localized to one area that can be removed.

Lung Cancer Part-6

Lung Cancer Part-6

How is lung cancer diagnosed?

Doctors use a wide range of diagnostic procedures and tests to diagnose lung cancer. These include the following:

• The history and physical examination may reveal the presence of symptoms or signs that are suspicious for lung cancer. In addition to asking about symptoms and risk factors for cancer development such as smoking, doctors may detect signs of breathing difficulties, airway obstruction, or infections in the lungs. Cyanosis, a bluish color of the skin and the mucous membranes due to insufficient oxygen in the blood, suggests compromised function due to chronic disease of the lung. Likewise, changes in the tissue of the nail beds, known as clubbing, also may indicate chronic lung disease.
• The chest X-ray is the most common first diagnostic step when any new symptoms of lung cancer are present. The chest X-ray procedure often involves a view from the back to the front of the chest as well as a view from the side. Like any X-ray procedure, chest X-rays expose the patient briefly to a small amount of radiation. Chest X-rays may reveal suspicious areas in the lungs but are unable to determine if these areas are cancerous. In particular, calcified nodules in the lungs or benign tumors called hamartomas may be identified on a chest X-ray and mimic lung cancer.
• CT (computerized tomography, computerized axial tomography, or CAT) scans may be performed on the chest, abdomen, and/or brain to examine for both metastatic and lung tumors. A CT scan of the chest may be ordered when X-rays do not show an abnormality or do not yield sufficient information about the extent or location of a tumor. CT scans are X-ray procedures that combine multiple images with the aid of a computer to generate cross-sectional views of the body. The images are taken by a large donut-shaped X-ray machine at different angles around the body. One advantage of CT scans is that they are more sensitive than standard chest X-rays in the detection of lung nodules, that is, they will demonstrate more nodules. Sometimes intravenous contrast material is given prior to the scan to help delineate the organs and their positions. A CT scan exposes the patient to a minimal amount of radiation. The most common side effect is an adverse reaction to intravenous contrast material that may have been given prior to the procedure. This may result in itching, a rash, or hives that generally disappear rather quickly. Severe anaphylactic reactions (life-threatening allergic reactions with breathing difficulties) to contrast material are rare. CT scans of the abdomen may identify metastatic cancer in the liver or adrenal glands, and CT scans of the head may be ordered to reveal the presence and extent of metastatic cancer in the brain.
• A technique called a low-dose helical CT scan (or spiral CT scan) is sometimes used in screening for lung cancers. This procedure requires a special type of CT scanner and has been shown to be an effective tool for the identification of small lung cancers in smokers and former smokers. However, it has not yet been proven whether the use of this technique actually saves lives or lowers the risk of death from lung cancer. The heightened sensitivity of this method is actually one of the sources of its drawbacks, since lung nodules requiring further evaluation will be seen in approximately 20% of people with this technique. Of the nodules identified by low-dose helical screening CTs, 90% are not cancerous but require up to 2 years of costly and often uncomfortable follow-up and testing. Trials are underway to further determine the utility of spiral CT scans in screening for lung cancer.

Lung Cancer Part-5

Lung Cancer Part-5

What are lung cancer symptoms and signs?

Symptoms of lung cancer are varied depending upon where and how widespread the tumor is. Warning signs of lung cancer are not always present or easy to identify. Lung cancer may not cause pain or even any symptoms at all in some cases. A person with lung cancer may have the following kinds of symptoms:

• No symptoms: In up to 25% of people who get lung cancer, the cancer is first discovered on a routine chest X-ray or CT scan as a solitary small mass sometimes called a coin lesion, since on a two-dimensional X-ray or CT scan, the round tumor looks like a coin. These patients with small, single masses often report no symptoms at the time the cancer is discovered.
• Symptoms related to the cancer: The growth of the cancer and invasion of lung tissues and surrounding tissue may interfere with breathing, leading to symptoms such as cough, shortness of breath, wheezing, chest pain, and coughing up blood (hemoptysis). If the cancer has invaded nerves, for example, it may cause shoulder pain that travels down the outside of the arm (called Pancoast syndrome) or paralysis of the vocal cords leading to hoarseness. Invasion of the esophagus may lead to difficulty swallowing (dysphagia). If a large airway is obstructed, collapse of a portion of the lung may occur and cause infections (abscesses, pneumonia) in the obstructed area.
• Symptoms related to metastasis: Lung cancer that has spread to the bones may produce excruciating pain at the sites of bone involvement. Cancer that has spread to the brain may cause a number of neurologic symptoms that may include blurred vision, headaches, seizures, or symptoms of stroke such as weakness or loss of sensation in parts of the body.
• Paraneoplastic symptoms: Lung cancers frequently are accompanied by symptoms that result from production of hormone-like substances by the tumor cells. These paraneoplastic syndromes occur most commonly with SCLC but may be seen with any tumor type. A common paraneoplastic syndrome associated with SCLC is the production of a hormone called adrenocorticotrophic hormone (ACTH) by the cancer cells, leading to oversecretion of the hormone cortisol by the adrenal glands (Cushing's syndrome). The most frequent paraneoplastic syndrome seen with NSCLC is the production of a substance similar to parathyroid hormone, resulting in elevated levels of calcium in the bloodstream.
• Nonspecific symptoms: Nonspecific symptoms seen with many cancers, including lung cancers, include weight loss, weakness, and fatigue. Psychological symptoms such as depression and mood changes are also common.