The trachea, also called the windpipe, is a narrow tube that connects the nose and mouth to the lungs. The tube divides into 2 airways called the bronchi, which open out into the lungs. Cancers of the trachea and the bronchi are termed as tracheobronchial cancer. These cancers are very rare and are mostly caused by the spread of cancer from another part of the body (metastasis).
Tracheobronchial cancers can be benign (noncancerous) or malignant (spread to other parts of the body). They cause airway obstruction and secondary lung infections. The symptoms of tracheobronchial cancers include:
- Cough (with or without blood)
- Difficulty in breathing
- High pitched sound while breathing (stridor)
- Difficulty in swallowing
- Repeated fever and chest infections
Tracheobronchial cancers are difficult to diagnose as most of the symptoms are mistaken for respiratory diseases such as asthma, bronchitis etc. Because of this, delay in diagnosis is common.
Some of the tests used to diagnose tracheobronchial cancer are:
- Imaging tests such as X-ray, CT scan (series of X-rays that create a 3D image) and MRI (use of magnetic field to create 3D images)
- Bronchoscopy (thin tube fitted with a camera is passed through your nose or mouth to examine your trachea)
- Biopsy (small sample of diseased tissue is removed for examination under the microscope)
Treatment for tracheobronchial cancer depends on your general health, size and position of the cancer and whether it has spread to other parts of the body. Treatment may include various bronchoscopic procedures or surgery.
Surgery is recommended for small cancers that cover less than half of the trachea. Your surgeon makes an incision in your neck, removes the tumour as well as a small part of the healthy tissue surrounding it and re-joins the ends of the trachea. The surgical procedure is generally complex as the blood supply to the trachea is very delicate and can be easily damaged. Surgery may be performed alone or in combination with radiotherapy and chemotherapy.
Radiation therapy is indicated for the following:
- Early, low-grade cancer
- Tumour involves more than 50% of the trachea
- Tumour that has spread to the nearby lymph nodes or other regions in the chest
- Poor general health
- After surgery, to relieve symptoms or prevent cancer recurrence
During the procedure, a beam of radiation is directed on the tumour from an external source to gradually reduce its size. This treatment may be given for 3 to 7 weeks based on the tumour size. Radiation therapy involves side effects such as tiredness, nausea and problems with swallowing.
Chemotherapy is indicated to treat the symptoms of tracheobronchial cancer or control the cancer to keep it from spreading. The procedure involves the use of anti-cancer drugs to destroy the tumour cells.
Bronchoscopic treatments make use of a bronchoscope to treat various symptoms of a cancer that may be blocking the airway and causing difficulties in breathing. Special instruments are threaded through the bronchoscope to reach the tumour and destroy it. It may be suggested if you are not a candidate for surgery. Some types of bronchoscopic treatments include:
- Laser therapy: A flexible fiber is passed through the bronchoscope to emit laser beams. The tumour is vaporized and the airway is cleared.
- Spray cryotherapy: A special cryotherapy catheter (narrow tube) is inserted through the bronchoscope. Liquid nitrogen is sprayed on the tumour to freeze it. This frozen tumour is then removed.
- Brachytherapy: A source of radiation is threaded through the bronchoscope and guided to the tumour site. This direct delivery of radiation helps minimize damage to the nearby healthy tissues.
- Photodynamic therapy: A light-sensitive drug is passed through your veins to be taken up by the tumour. Strong laser light is directed at the tumour through the bronchoscope, which activates the drug and destroys the cancer.
- Rigid coring: A rigid bronchoscope is inserted through the trachea and pushed through the tumour to open the airway. This treatment is used for temporary control of the symptoms.
The above procedures can be performed individually or in combination. These techniques can be used in some cases to reduce the size of the tumour so that it can be surgically removed.