Lung Cancer Down, But Subtype Trends Vary by Demographics

Although the leading cancer killer of both men and women in the U.S. affects the lungs, incidence rates have been falling across the country. A new (NCI) analysis of data on over 450,000 lung cancer patients brings good news and helpful information. It expanded the scope of previous investigations by discovering that rates vary according to cancer subtype classification, gender, race/ethnicity and age.

Identifying Unique Characteristics

Epidemiologist Dr. Denise Riedel Lewis and her NCI colleagues confirmed that U.S. lung cancer rates have declined by approximately 12 percent overall during nearly the last three decades. CANCER, an American Cancer Society (ACS) peer-reviewed journal, published the findings based on the Surveillance, Epidemiology and End Results (SEER) program, a cancer incidence and survival resource. The research team examined rates within Caucasian and African-Americans who received diagnoses from 1977 to 2010 as well as non-white Hispanic residents, Asian/Pacific Islanders and white Hispanics from 1992-2010 diagnoses. Squamous and small-cell carcinoma rates decreased since the 1990s, but they fell at a much steeper rate in males than females. Rates for unspecified lung cancers also dropped during this period. Adenocarcinoma rates went down in males until 2005, when they rose quickly until 2010 among every racial, ethnic and gender group. Most recent adenocarcinoma rates were higher in young females than males in all demographic groups. The researchers also found that the ratios of lung cancer rates for males and females declined more among black and white people than other racial and ethnic groups. Since smoking causes 90-95 percent of lung cancers in the United States, the authors inferred that lower rates reflect the nation’s decreasing smoking habits. Frequency, duration, cessation rates and cigarette composition influence bodily toxin levels. Now patients can benefit from increased awareness and surveillance based on unique personal factors. Dr. Norman Edelman, American Lung Association senior medical advisor, noticed how gender differences in lung cancer rates are evolving. Rates in men and women are converging, so they’re almost equal now because men’s rates are declining while they’ve plateaued in women. Because females took up smoking later than males, women’s long-term effects occurred on a delayed schedule, compared with men. The rate of lung cancer among women will decline, he says, in time — just as it did in men.

Examining Negative Findings

Lewis found that adenocarcinoma lung cancer, which the American Cancer Society claims accounts for about 40 percent of all lung cancers, is on the rise. Edelman said that this cancer may develop because people are smoking differently. “The deeper you breathe in smoke, the more likely the cancer-causing tars are going to get into the outer area of the lungs,” he said, “and that’s where adenocarcinoma starts.” Low-tar, low-nicotine light cigarettes may be to blame for the upsurge of adenocarcinoma cases. People have to inhale more deeply and smoke more to get the amount of nicotine they want. Fortunately, this cancer tends to grow more slowly than other subtypes, so most patients receive diagnoses and treatment before adenocarcinoma spreads outside their lungs. Squamous cell carcinomas dropped less rapidly than they did in the past. According to the ACS, they comprise about 30 percent of all lung cancers and affect cells lining the airways and in the middle of the lungs.

Understanding Your Risk

Watch this Khan Academy and American Association of Colleges of Nursing video to learn how smoking, radon gas and air pollution increase your lung cancer risk. It prefaces this important information with lung anatomy basics, so keep viewing it until the end.

Recognizing Typical Symptoms

Your lungs are two spongy organs in your chest that take in oxygen when you inhale and release carbon dioxide when you exhale. Cancer makes cells multiply uncontrollably, taking up too much space. This impairs gas exchange and your lungs’ ability to expel dirt. According to the Mayo Clinic, lung cancer doesn’t cause symptoms in its earliest stages typically. Bothersome signs tend to occur only when the disease is in an advanced stage. At that point, you may notice:

• A new cough that doesn’t go away
• Changes in a chronic cough
• Smoker’s cough
• Blood, even small amounts, when coughing
• Shortness of breath
• Chest pain
• Wheezing
• Hoarseness
• Weight loss without trying
• Bone pain
• Headache

Seeking Diagnosis and Treatment

Several organizations recommend people with increased lung cancer risks consider annual screenings. If you’re 55 or older and a current or former smoker, talk with your doctor about early detection through computerized tomography (CT) scans. Make an appointment with your physician if you have any signs or symptoms that worry you. These tests can look for cancerous cells:

• Imaging tests
• Sputum cytology
• Biopsies

If you receive a lung cancer diagnosis, targeted drug therapy map be an option. This newer cancer treatment targets specific abnormalities in cancer cells. Tarceva (Erlotinib) blocks chemicals that signal cancer cells to grow and divide. It slows their progression and inhibits them from spreading. To quit smoking, prescription medications like Chantix and over-the-counter nicotine replacement products like Nicorette Gum can help. Whenever you experience shortness of breath:

• Relax by listening to music, imagining your favorite vacation spot, meditating or praying
• Find a comfortable position, maybe leaning forward
• Concentrate on moving the muscles that control your diaphragm
• Save your energy for essential tasks