Symptoms and Diagnosis of Lung Cancer

Every year, lung cancer accounts for more deaths in the United States than any other form of cancer. Based on estimates released by the American Cancer Society, more than 160,000 Americans die from lung cancer each year.

The majority (over 85 percent) of lung cancer cases are caused by long-term cigarette usage. Tobacco smoke is known to contain a number of carcinogenic materials. Because these carcinogenic materials build up in the lungs over time, the longer and more often a person smokes, the more likely he or she is to develop lung cancer.

General Lung Cancer Symptoms

One of the reasons lung cancer is so deadly, is that symptoms often do not manifest until the cancer has progressed to an advanced state. In fact, in 25 percent of all cases, individuals diagnosed with lung cancer showed no signs or symptoms whatsoever. Rather, the cancer was identified during a routine doctor's visit or while investigating an unrelated illness.

For the other 75 percent of cases, symptoms can vary depending on the specific type of lung cancer. In general, however, the growth of the tumor will aggravate lung tissue and surrounding tissue. This often results in symptoms such as:

• Difficulty breathing
• Frequent coughing
• Shortness of breath
• Chest pain
• Hoarseness
• Wheezing
• Coughing up blood
• Difficulty swallowing

Secondary Lung Cancer Symptoms

A number of secondary symptoms may also result from lung cancer. These include:

• Loss of appetite
• Fatigue
• Unexpected weight loss
• Swelling of the face or neck
• Finger clubbing (changes in shape of the fingers and nails)

Hormonal Lung Cancer Symptoms

A few types of lung cancer produce and release hormone-like substances into the bloodstream. Oftentimes, this causes an imbalance in hormones and can result in a number of unique symptoms. Most often, hormonal symptoms are related to Small Cell Lung Cancer (SCLC). These symptoms may not be immediately identifiable and are less common than other symptoms, but include:

• Muscle weakness
• Constant drowsiness
• Dizziness and confusion
• Blood clots
• Swelling of the breasts (for men)

Symptoms of Pancoast Lung Cancer

A pancoast lung cancer tumor is defined as one that grows at the top of the lung. Pancoast tumors often press directly against or damage the nerve that runs from the neck to the side of the face. This interference can result in such unique symptoms as:

• Severe pain in the shoulder
• Drooping in one eyelid
• Weakness or a small pupil in one eye
• Reduced ability to sweat on one side of the face

When to See the Doctor About Lung Cancer

Long-term smokers are often advised by doctors to undergo routine checkups for lung cancer. This is due to the lack of symptoms in early stages of the disease. Through routine checkups, lung cancer can often be caught earlier than would be otherwise possible. As with many types of cancer, the earlier lung cancer is diagnosed, the better the chance for survival.

Beyond routine checkups, a person that exhibits any of the symptoms listed above may need to be checked for lung cancer. Early symptoms that are most commonly felt by individuals with lung cancer include persistent cough, coughing up blood, repeated bouts of bronchitis, chest pain and fatigue.

Indicators That May Suggest Lung Cancer

In cases where no symptoms are present, a doctor may employ a number of simple tests to determine if lung cancer should be a concern. During routine exams, the doctor may look for swollen lymph nodes, an abnormal mass in the abdomen and shallow breathing. Additionally, the use of a stethoscope may help the doctor identify abnormal sounds in the lungs or dullness when the chest is tapped.

Routine blood tests can also help point a doctor towards the formation of lung cancer. In many cases, the tumor causes elevated levels of calcium or specific hormones. A blood sample with such abnormalities may lead the doctor to pursue confirmation of the disease.

Diagnosing Lung Cancer

If a doctor suspects the formation of lung cancer, then a chest X-ray may be ordered. If the X-ray shows suspicious areas in the lungs, then lung cancer may be the cause. However, these suspicious areas are frequently the result of other, non-harmful causes such as calcium deposits and benign tumors.

When an X-ray proves inconclusive, sometimes a CT scan or MRI is performed on the chest. CT scans and MRIs are more sensitive at picking up suspicious areas in the lungs, and therefore can provide additional details and evidence for the doctor. In addition to a chest scan, scans may also be performed on the abdomen or brain to check for lung cancer growths that have spread beyond the lungs.

If an X-ray, CT scan or MRI causes a doctor to suspect lung cancer, then additional tests are required to confirm the diagnosis. The simplest way to diagnose lung cancer is through sputum analysis. Sputum is essentially mucus or phlegm. In some cases, viewing sputum cytology under a microscope will yield visual confirmation of tumor cells. However, such cancerous cells are not always present in individuals with lung cancer.

In some types of lung cancer, pleural fluid collects in the chest cavity. If such is the case, then the doctor may order a thoracentesis, which involves using a long needle to extract a sample of the fluid. The fluid is then examined under a microscope to check for the presence of cancerous cells.

The most common and effective way of diagnosing lung cancer is by collecting a biopsy of lung tissue. A biopsy may be collected in a number of ways. The most common method is by passing a lighted tube from the nose into the lungs (bronchoscopy). Alternative measures include making an incision in the neck (mediastinoscopy) and inserting a needle through the chest (needle biopsy).

Diagnosing the Stage of Lung Cancer

Once lung cancer has been properly diagnosed, the doctor will attempt to determine both the size of the tumor and how far the cancer has spread throughout the body. This step is called staging.

There are four stages of lung cancer. Identifying which stage a specific case of lung cancer is currently helps determine the best course of action in regards to treatment. Each stage of lung cancer is defined below:

• Stage I: cancer is confined to the lung tissue
• Stage II: cancer cells have spread to nearby lymph nodes or the chest wall
• Stage III: cancer cells are present in lymph nodes beyond the center of the chest, and/or in localized areas such as the heart, blood vessels, trachea and esophagus
• Stage IV: cancer has metastasized in the brain, bones, liver or other parts of the body