What Are the Criteria for Lung Cancer Screening?

Lung cancer symptoms often do not appear until the cancer is advanced when is difficult to treat and has a poor prognosis. There are different criteria for lung cancer screening, which generally include being over age 50, a current smoker, having quit smoking within the past 15 years, and having a 20 or more pack per year habit.
Lung cancer symptoms often do not appear until the cancer is advanced when is difficult to treat and has a poor prognosis. There are different criteria for lung cancer screening, which generally include being over age 50, a current smoker, having quit smoking within the past 15 years, and having a 20 or more pack per year habit.

Symptoms of lung cancer often do not appear until the cancer is advanced. Lung cancer that is advanced is difficult to treat and has a poor prognosis. For this reason, it is recommended that people with a higher risk of getting lung cancer, such as smokers, get screened regularly for lung cancer

A test called a low dose computerized tomography (CT) scan, or LDCT, is typically used. 

The American Cancer Society recommends lung cancer screening for people who are: 

  • 55 to 74 years old, and
  • In fairly good health, and 
  • Current smokers or who have quit in the past 15 years, and
  • Have at least a 30-pack per year smoking history

The U.S. Preventive Services Task Force (USPSTF) has similar criteria and recommends annual lung cancer screening with LDCT for people who:

  • Have a 20 pack per year or more smoking history, and
  • Smoke now or have quit within the past 15 years, and
  • Are between 50 and 80 years old

The USPSTF recommends yearly lung cancer screening stop when the person being screened: 

  • Turns 81 years old, or
  • Has not smoked in 15 or more years, or
  • Develops a medical condition that makes them unwilling or unable to have surgery if lung cancer is detected

What Are Symptoms of Lung Cancer?

Lung cancer may not have symptoms early on. When the first signs and symptoms do occur, they may include:

  • Persistent or worsening cough
  • Coughing up blood or rust-colored sputum
  • Shortness of breath
  • Breathing problems
  • Chest pain that may be worse with deep breathing, coughing, or laughing
  • Hoarseness
  • Loss of appetite
  • Unexplained weight loss
  • Fatigue/tiredness
  • Weakness
  • Wheezing
  • Respiratory infections such as bronchitis and pneumonia that don’t go away or recur

What Causes Lung Cancer?

The main cause of all types of lung cancer is smoking, which is responsible for 80% of all lung cancer deaths, as well as many deaths from exposure to secondhand smoke. Smokers exposed to radon and asbestos are at higher risk. 

In non-smokers, causes of lung cancer include:

  • Air pollution
  • Secondhand smoke
  • Exposure to radon
  • Workplace exposure to asbestos, diesel exhaust, or other chemicals 
  • Genetic changes

How Is Lung Cancer Diagnosed?

In addition to regular cancer screening, if lung cancer is suspected, imaging tests may be used to diagnose it, such as:

Lab tests used to diagnose lung cancer include:

  • Sputum cytology 
  • Thoracentesis 
  • Tissue biopsy 
  • Bronchoscopy masses
  • Endobronchial ultrasound 
  • Endoscopic esophageal ultrasound
  • Mediastinoscopy and mediastinotomy
  • Thoracoscopy
  • Lung function tests
  • Molecular tests for gene changes 
  • Tests for certain proteins on tumor cells
  • Blood tests

What Is the Treatment for Lung Cancer?

Treatment for lung cancer depends on the stage, and may include:

  • Surgery
    • Removal of the tumor (stage 0)
    • Removal of the lobe of the lung that has the tumor (lobectomy) or removal of a smaller piece of the lung (sleeve resection, segmentectomy, or wedge resection) (Stage 1)
    • Lobectomy or sleeve resection or removal of the entire lung (pneumonectomy) (Stage 2 and later stages)
  • Photodynamic therapy (PDT)
  • Laser therapy
  • Adjuvant chemotherapy 
  • Radiation therapy
  • Radiofrequency ablation (RFA) 
  • Lymph node removal
  • Chemotherapy 
  • Targeted therapy 
  • Immunotherapy with pembrolizumab (Keytruda) or durvalumab (Imfinzi)
  • Participation in clinical trials

Stage IV lung cancers are widespread and very hard to treat and cure. Any of the above treatments may be used to help patients live longer, but they are unlikely to cure the disease at this stage. 

References
https://www.cancer.org/cancer/lung-cancer.html

https://www.cdc.gov/cancer/lung/basic_info/screening.htm