What is Lung Cancer?

Lung cancer is a malignant tumor that grows in one or both lungs. Lung cancer usually forms in the cells that line the airways and nearby glands. In lung cancer the changing of normal cells into cancerous cells usually happens over a period of years.
Types of Lung Cancer

Primary lung cancers, which originate in the lungs, are divided into two main types, Small Cell Lung Cancer (SCLC) and Non-Small Cell Lung Cancer (NSCLC). Early detection determines the type and the treatment.

Small Cell Lung Cancer
Represents about 20% of diagnosed cancers. It is often tied to smoking and because it can spread quickly is frequently treated with chemotherapy rather than surgery.

Non-Small Cell Lung Cancer
Three types of NSCLC represent approximately 80% of lung cancer diagnoses. Each develops in distinct areas of the lung, and behave in similar ways, though rate of growth varies.

Squamous Cell Carcinoma
Accounts for about 30% of all non-small cell lung cancers and is often tied to smoking. It is generally detected in one of the main airways (bronchi) and develops relatively slowly.

Adenocarcinoma
Is the most common subtype and accounts for 30-35% of all NSCLC. These types of tumors usually develop at the edges of the lungs and can also be found in cells in the airways. They are often slow growing and don't typically cause symptoms in their early stages.

Large Cell Carcinoma
Accounts for 10-20% of all NSCLC. It can occur in any part of the lung, and grows and spreads quickly. Like squamous cell carcinomas these tumors are associated with smoking.
Lung Cancers Toll

Lung cancer is the leading cause of cancer mortality in both men and women worldwide,
with 1.3 million people dying from the disease each year.
  • The American Cancer Society estimates that there will be 219,440 new cases of lung cancer annually
    in the United States, and about 159,390 people die each year from the disease.


  • Lung cancer is responsible for almost 1/3 of all cancer deaths in the U.S.

  • Among women, lung cancer is responsible for more cancer deaths than breast cancer and all
    gynecological cancers combined.


  • Breast cancer death rates have been pretty stable at 40,000 deaths per year, while 80,000 women die of lung cancer annually.

  • Lung cancer is often diagnosed in a late stage associating it with a poor prognosis for disease free survival.

  • The link between smoking and lung cancer is well established. 50% of new lung cancer cases are former
    smokers. There are currently 50 million former smokers in the u.s.


  • Of people diagnosed with lung cancer, 15% have never smoked.
Lung cancer is seriously under-funded. The nation's research investment in lung cancer
lags dramatically behind funding for other cancers.
LCRF Statement on Lung Cancer Screening May 2012

Recently, the National Lung Screening Trial (NLST) reported positive benefits for CT screening vs chest Xrays for high risk populations of current and former heavy smokers. The study showed a 20% decreased risk of dying from lung cancer for those screened with annual CT scans compared to chest Xrays.

Although this is important new information for this high-risk population, CT scan screening identifies abnormalities in 1 of 4 people tested, most of which are not cancer. It is also not clear from this study that other groups with less or no smoking exposure will gain the same benefit.

A consensus statement was made in May 2012 by the American College of Chest Physicians, American Society of Clinical Oncology and the National Comprehensive Cancer Network recommending annual CT scans for high risk patients. Such high risk patients are defined as those 55 years or older who have smoked a pack of cigarettes or more daily for at least 30 years. For patients not included in this high risk category, there has been no screening guideline consensus reached. The LCRF recommends you discuss these recommendations further with your individual practitioner who will take into consideration this data, your specific history and individual risk factors
Lung Cancer Prevention

Risk Factors
  • Tobacco: There is clear-cut evidence of the link between tobacco use and lung cancer. The number of tobacco-related lung cancers is 90% for men and 78% for women in the US. People who stop smoking can lower their risk of lung cancer. Second-hand smoke or passive intake also increases the risk of lung cancer.

  • Environmental causes: Although there are numerous specific agents, their impact is lower than smoking. Causes include asbestos, radon, arsenic, chromium, nickel, tar and soot. Pollution may be a cause of lung cancer. Cities with higher pollution rates have higher numbers of lung cancer cases.

  • Beta-carotene: Studies show heavy smokers who take betacarotene supplements have higher rates of lung cancer than those who do not.

  • Diet and physical activity: Diets rich in fruits and vegetables can lower the risk of lung cancer. Heavy alcohol use may increase the risk of lung cancer. Exercise may reduce the risk of lung cancer, even in smokers.
Warning signs for lung cancer you should discuss with your doctor

Persistent cough, Chest pain, Weight loss and/or decreased appetite, Bloody sputum, Shortness of breath, Hoarseness, Fever for unknown reasons, Recurrent infections such as bronchitis or pneumonia.

Sources:
The American Cancer Society
National Cancer Institute