What Is Usually the First Sign of Lung Cancer?

Early lung cancer may have no symptoms, but a cough, shortness of breath and loss of appetite are common early signs?

Lung cancer is a type of cancer that occurs when lung cells become abnormal and grow out of control. 

There are different types of lung cancer:

• Non-small cell lung cancer is the most common type of lung cancer and accounts for 80% to 85% of cases
• Small cell lung cancer (also called oat cell cancer) accounts for 10% to 15% of cases
• Other types of tumors that can form in the lungs include: 
  • Lung carcinoid tumors, which account for fewer than 5% of lung tumors
  • Other lung tumors: adenoid cystic carcinomas, lymphomas, and sarcomas, and benign lung tumors such as hamartomas are rare
  • Cancers that originate in other organs such as the breast, pancreas, kidney, or skin can spread (metastasize) to the lungs, but these are not lung cancers

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

If lung cancer spreads (metastasizes) to other parts of the body, symptoms may include:

• Bone pain, such as in the back or hips
• Nervous system effects from lung cancer that has metastasized to the brain 
  • Headache
  • Weakness or numbness of extremities
  • Dizziness
  • Problems with balance 
  • Seizures
• Yellowing of the skin and eyes (jaundice) from cancer spread to the liver
• Swollen lymph nodes such as those in the neck or above the collarbone

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

In non-smokers, causes of lung cancer include:

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

Symptoms of lung cancer often do not appear until the cancer is advanced. For this reason, The American Cancer Society has lung cancer screening guidelines for people with a higher risk of getting lung cancer, such as smokers. 

The American Cancer Society recommends people who are 55 to 74 years old, are in fairly good health, are current smokers or who have quit in the past 15 years, and have smoked a certain number of cigarettes per day should receive regular lung cancer screenings. A test called a low-dose CAT scan or CT scan (LDCT) is typically used. 

If lung cancer is suspected, imaging tests may be used to diagnose it, such as:

• Chest X-ray
• Computed tomography (CT) scan
• Magnetic resonance imaging (MRI)
• Positron emission tomography (PET) scan
• Bone scan

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
  • Complete blood count (CBC) 
  • Blood chemistry

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 
• Immunotherapy with pembrolizumab (Keytruda), durvalumab (Imfinzi), or pembrolizumab (Keytruda)
• 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. 

Life expectancy for lung cancer is often expressed in 5-year survival rates, that is, how many people will be alive 5 years after diagnosis. 

Non-small cell lung cancer 5-year survival rates:

• Localized (cancer that has not spread outside the lung): 61%
• Regional (cancer has spread outside the lung to nearby structures or lymph nodes): 35%
• Distant (cancer has spread to distant parts of the body, such as the brain, bones, liver, or the other lung): 6%

Small cell lung cancer 5-year survival rates:

• Localized (cancer that has not spread outside the lung): 27%
• Regional (cancer has spread outside the lung to nearby structures or lymph nodes): 16%
• Distant (cancer has spread to distant parts of the body, such as the brain, bones, liver, or the other lung): 3%

The best way to prevent lung cancer is to not smoke and to avoid secondhand smoke. 

Other ways to help reduce the risk of developing lung cancer include:

• Avoiding exposure to radon 
• Limit or avoid exposure to asbestos, diesel exhaust, and other cancer-causing agents
• Eat a healthy, balanced diet with plenty of fruits and vegetables