What are the symptoms of lung cancer? You should be suspicious if you have a nagging cough that brings up blood-streaked sputum, more so if you smoke and have a family history of the disease. Other warning signs are shortness of breath, hoarseness, chest pain, arm or shoulder pain, loss of appetite and weight.

"Generally, lung cancer is first suspected because of your physical symptoms or because an abnormal mass appears on a routine chest X-ray. Loss of appetite and weight may be the first signs of a lung cancer. In this case, the first step is to determine with certainty whether or not cancer is present. In addition to a regular chest X-ray, tomograms (special chest X-rays that give a highly localized view of the lung) or other special studies such as a CT scan may be obtained," according to Dr. David E. Larson, editor-in-chief of the "Mayo Clinic Family Health Book."

Unfortunately, lung cancer happens to be one of the hardest cancers to detect since it can be present for 10 to 20 years without causing any noticeable symptom. Five to 10 percent of cases are discovered accidentally during a routine X-ray exam.

Common symptoms like coughing, wheezing, and aches are often ignored or mistaken by the patient for something else. By the time symptoms appear, the disease may have reached an incurable stage. This explains the poor prognosis of most patients with the disease.

The easiest way to avoid lung cancer is to stop smoking. It may be difficult to quit but it is not impossible. Millions of people have done it and those who quit lessen their chances of developing lung cancer by two-thirds.

Ninety percent of people who stop smoking do it on their own so start now before it's too late. If you find that hard to do, you can join smoking cessation classes or enroll in a clinic that offers the same service. Choose the program that makes the most sense to you and enlist the help of friends or loved ones to make things easier for you.

For those with cancer who can still be helped, surgery is the preferred treatment. Chemotherapy and radiation are recommended depending on the type of cancer, the patient's age and overall health, and the extent of the disease.

"A cancerous tumor in the lung is usually removed surgically. It is sometimes necessary to remove an entire lobe of the lung. Because lung cancers are usually not detected until they are well advanced, surgery alone may not be able to eliminate them, and radiation and chemotherapy may be used in combination with or in place of surgery," explained the editors of Consumer Guide's "Family Health & Medical Guide."

Which treatment is best for you? Only your doctor can answer that. But here are some suggestions from Dr. Isadore Rosenfeld of the New York Hospital - Memorial Sloan-Kettering Cancer Center in "The Best Treatment":

"Here is what I recommend to my own patients with lung cancer. If the cancer, regardless of its cell type, appears not to have spread and lung function is good, then surgery should be done without delay, and in all age groups, even in the elderly who are otherwise in good health. Oat cell cancers are treated with chemotherapy and radiation, as recommended by an oncologist.

"If CT scans and other tests indicate that it's too late for surgery (because the cancer has already spread to the glands in the opposite side of the chest or elsewhere), I leave it alone if it's not causing any symptoms. I prescribe radiation, surgery, or chemotherapy only if the incurable cancer is causing symptoms. The purpose of intervention at this point is to make the person feel better. When a patient with advanced lung cancer has no complaints, I have them do nothing. This approach is not shared by all or even most doctors. The majority of my colleagues go full-blast with radiation, surgery, and toxic chemotherapy in the hope of obtaining a cure, which rarely, if ever, happens at that stage. Such treatment, in my experience, often accelerates or prolongs suffering," Rosenfeld concluded. (Next: Breast cancer.)