Understanding Lung Metastases: When Cancer Spreads to the Lungs
 

This information sheet is designed to help you understand what it means when cancer from another part of your body spreads to your lungs (lung metastases). It also covers treatment options, including surgery (pulmonary metastasectomy) and other therapies.
 

What are Lung Metastases?
 

Sometimes, cancer cells can break away from where they first started (the primary tumour) and travel through the bloodstream or lymphatic system to other parts of the body. When these cells reach the lungs and start to grow, they form new tumours. These are called lung metastases or secondary lung cancer.
 

It's important to understand that lung metastases are not the same as primary lung cancer (cancer that starts in the lungs). The cancer cells in the lungs are the same type as the original (primary) cancer. For example, if breast cancer spreads to the lungs, it is treated as metastatic breast cancer, not primary lung cancer.
 

Which Cancers Commonly Spread to the Lungs?
 

Many types of cancer can spread to the lungs. Some of the most common ones include:
 

• Breast cancer

• Colorectal cancer (bowel cancer)

• Kidney cancer (renal cell carcinoma)

• Sarcomas (cancers of bone or soft tissues like muscle or fat)

• Melanoma (a type of skin cancer)

• Head and neck cancers

• Testicular cancer

• Thyroid cancer

• Bladder cancer

• Osteosarcoma (a type of bone cancer, especially common in children and young adults)
   

Having one of these cancers does not automatically mean it will spread to the lungs, but it is a possibility.
 

Symptoms of Lung Metastases
 

Lung metastases may not cause any symptoms, especially if they are small or few in number. They are often found during follow-up scans after treatment for a primary cancer.
 

If symptoms do occur, they can include:
 

• Persistent cough (sometimes coughing up blood)

• Shortness of breath (dyspnoea)

• Chest pain or discomfort

• Repeated chest infections

• Unexplained weight loss

• Fatigue (extreme tiredness)
   

These symptoms can also be caused by other conditions, so it's important to tell your doctor if you experience them.
 

How are Lung Metastases Diagnosed?
 

If your doctor suspects lung metastases, they may recommend one or more of the following tests:
 

• Chest X-ray: Can show larger tumours or areas of concern.

• CT (Computed Tomography) Scan: Provides more detailed images of the lungs and can detect smaller metastases.

• PET (Positron Emission Tomography) Scan: Can help identify cancerous areas throughout the body and see if the cancer is confined to the lungs or has spread elsewhere.

• Biopsy: In some cases, a small sample of tissue may need to be taken from a lung nodule to confirm it is a metastasis and to determine its type. This can be done via:

  • Bronchoscopy: A thin, flexible tube with a camera is passed down your airway.

  • Needle Biopsy: A needle is guided through the chest wall into the lung nodule, often using CT or ultrasound guidance.

  • Surgical Biopsy: Sometimes a surgical procedure is needed to get a sample.
     

Treatment for Lung Metastases
 

Treatment for lung metastases depends on many factors, including:
 

• The type and location of the primary cancer

• The number, size, and location of the metastases in the lungs

• Whether the cancer has spread to other parts of the body

• Your overall health and fitness

• Your personal preferences
   

The main goal of treatment may be to cure the cancer (if possible), to control its growth and spread, or to relieve symptoms and improve quality of life.
 

1. Pulmonary Metastasectomy (Surgery)
 

What is it?
 

Pulmonary metastasectomy is surgery to remove cancerous tumours (metastases) from the lungs. It is considered when the primary cancer is controlled or has been successfully treated, and the metastases are only in the lungs (or in a very limited number of other sites that can also be treated).
 

When is it considered?
 

Your doctor might consider you for this surgery if:

• The primary cancer is under control or has been removed.

• The metastases are only in the lungs (or limited other sites that can also be treated).

• It is possible to remove all visible metastases in the lungs.

• You are fit enough for the surgery and have enough healthy lung tissue remaining to breathe well afterwards.

• The type of primary cancer is one where removing lung metastases has been shown to improve outcomes (e.g., colorectal cancer, sarcoma, some kidney cancers).
   

Types of Surgery:
 

The type of surgery depends on the number, size, and location of the metastases.

• Wedge Resection: Removal of the tumour and a small, wedge-shaped piece of surrounding lung tissue. This is common when metastases are small and near the lung surface.

• Segmentectomy: Removal of a larger segment of the lung.

• Lobectomy: Removal of an entire lobe of the lung (if metastases are large or multiple within one lobe). This is less common for metastases than for primary lung cancer.
  Laser resection of pulmonary metastases allows for lung preservation and repeat procedures if necessary.

• Surgery can be performed via thoracotomy (a larger incision in the chest) or minimally invasive techniques like Video-Assisted Thoracoscopic Surgery (VATS) or Robot-Assisted Thoracic Surgery (RATS), which use smaller incisions.
   

Recovery:
 

Recovery time varies. You will likely spend several days in the hospital. Full recovery can take several weeks to months.
 

2. Systemic Therapies
 

These treatments travel through the bloodstream to reach cancer cells throughout the body.
 

• Chemotherapy: Uses anti-cancer drugs to kill cancer cells. The type of chemotherapy depends on the primary cancer type.

• Hormone Therapy: Used if the primary cancer is hormone-sensitive (e.g., some breast cancers).

• Targeted Therapy: Drugs that target specific molecules involved in cancer cell growth and survival. These are specific to the type of primary cancer and its genetic makeup.

• Immunotherapy: Helps your own immune system fight cancer. This is becoming an important treatment for various cancers that can spread to the lungs.
   

Systemic therapies may be given before or after surgery, or as the main treatment if surgery is not an option.
 

3. Localised Non-Surgical Treatments
 

These treatments target the metastases directly without major surgery.
 

• Stereotactic Body Radiotherapy (SBRT) / Stereotactic Ablative Radiotherapy (SABR): Delivers very precise, high doses of radiation to the tumours over a few sessions. It can be an option for patients who cannot have surgery or have a small number of metastases.

• Ablation Therapies (e.g., Radiofrequency Ablation - RFA, Microwave Ablation - MWA): Use heat generated by electrical currents or microwaves to destroy tumour cells. A probe is inserted through the skin into the tumour, guided by imaging. These are typically used for smaller tumours when surgery is not suitable.
   

4. Palliative Care / Symptom Control
 

If the cancer is widespread or treatments are not controlling its growth, the focus may shift to palliative care. This aims to manage symptoms, improve quality of life, and provide emotional and practical support. It can include radiotherapy to relieve pain or breathlessness, medication, and other supportive measures.
 

Questions to Ask Your Doctor
 

• What type of primary cancer has spread to my lungs?

• How many metastases are in my lungs, and where are they located?

• Has the cancer spread to any other parts of my body?

• What are my treatment options?

• Is pulmonary metastasectomy (surgery) an option for me? What are the potential benefits and risks?

• What other treatments (e.g., chemotherapy, radiotherapy, immunotherapy) might be suitable?

• What is the goal of the recommended treatment (e.g., cure, control, symptom relief)?

• What are the potential side effects of each treatment?

• How will treatment affect my daily life?

• Are there any clinical trials I might be eligible for?

• What is my prognosis (outlook)?
   

Disclaimer: This information sheet is intended for general knowledge and informational purposes only, and does not constitute medical advice. It is essential to consult with your doctor or other qualified healthcare provider for any questions you may have regarding a medical condition or treatment options. Do not disregard professional medical advice or delay in seeking it because of something you have read in this document.