Tumors that originate in the trachea (windpipe) are rare. Tumors that metastasize (spread) to the trachea from other areas, such as the thyroid, esophagus, larynx (voice box) or lung, are more common though may only account for two percent of all upper respiratory tumors.
No matter where these tumors originate and whether or not they are benign or malignant, they generally result in a narrowing of the opening of the trachea, restricting airflow to the lungs.
There are three types of carcinomas (malignant tumors) that are common in the trachea:
- Squamous cell carcinoma, which is found more often in men between the ages 50 and 70 and usually associated with smoking. A fast growing tumor, it may not be diagnosed until it’s too big to remove.
- In contrast to squamous cell carcinoma, adenoid cystic carcinomas, which spread along the lining of the trachea, are usually slow growing and not related to smoking. They occur equally in men and women between the ages of 40 and 60.
- A carcinoid tumor, which is a slow-growing abnormal mass that originates in the cells of endocrine (hormonal) or nervous system. These tumors may occur anywhere in the body, including the trachea.
Tracheal tumors may also be benign (not cancerous) but still cause a problem due to restricted airflow through the trachea, potential malignancy and growth too large to treat easily:
- Chondromas, the most common type of tracheal tumors, form from cartilage that makes up the trachea. This type of tumor may turn cancerous after a period of time.
- Hemangiomas, tumors in tiny blood vessels, may affect both children and adults. If a child with a hemangioma birthmark suddenly experiences breathing problems, a hemangioma tumor should be investigated.
- Papillomas are tumors caused by the human papilloma (HPV) virus. Papillomatosis refers to multiple papilloma tumors.
Due to the effect tracheal tumors may have on the windpipe, breathing difficulties are often the first sign of a problem whether the tumor is benign or malignant (cancerous). Still, breathing problems may result from tracheal stenosis, asthma, bronchitis or chronic obstructive pulmonary disease (COPD), so your doctor will look for the following symptoms as well:
- Wheezing, shortness of breath and coughing, with or without blood.
- Noisy breathing, including a gasping sound.
- Frequent upper airway infections.
- Difficulty swallowing and hoarseness, which may indicate the tumor has grown beyond the trachea and is pressing against the esophagus.
Causes and Risk Factors
The most common tracheal tumor, squamous cell carcinoma, is thought to be a direct result of smoking. If you are a smoker, your doctor can recommend resources for quitting. Another risk factor is a hemangioma, which may spread from the face to the neck.
It is recommended that you check with your physician if you experience any of the symptoms listed above, if only to rule out a tumor as the cause.
Tracheal tumors are difficult to diagnose because they are so rare and, in most cases, slow growing. They may be misdiagnosed as another breathing problem, such as asthma, bronchitis, or COPD, because there are no specific symptoms. Your doctor may order one or more of the following tests to determine the cause of your breathing problems:
- Computed tomography (CT) scans. These scans show pictures that can define the size of a tumor, narrowing of the trachea and the status of the surrounding lymph nodes.
- Bronchoscopy. A bronchoscope (a tube with a tiny camera at the end) is inserted into the trachea. This allows your physician to see any abnormalities in the trachea as well as remove cells to test for cancer (biopsy). Virtual bronchoscopy is a “picture” of the trachea by a CT scan without the need for a bronchoscope. This cannot produce a biopsy but can take an excellent image to see the extent of the tumor.
- Pulmonary function testing. This measures how well the lungs are working and may discover a classic pattern that suggests a blockage in the trachea.
There are several options for treating tracheal tumors. Some treatments are for cure and some are aimed at reducing symptoms. Contraindications to the removal of a tumor may occur when the tumor is too large, has invaded surrounding areas that cannot be resected (removed) or have spread to other areas of the body. Some surgical and nonsurgical treatments include:
- A tracheobronchial airway stent. A tube made of metal, silicone or other material, is inserted into the trachea to keep the airway open.
- An operation to remove part of the trachea and the tumor, which is the preferred treatment, if feasible. The surgeon then connects the remaining ends to each other. Other special techniques may be used to pull together the ends of the trachea to connect them.
- Laser therapy may be used, which, essentially, vaporizes the tumor.
- Photodynamic therapy. This is a multi-step, outpatient procedure. A medicine (Photofrin) is injected into your veins. Over the next two days, the medicine is concentrated into the tumor but not active. Then, a bronchoscope aims a laser light at the tumor to activate the Photofrin and destroy the tumor. A few days after that, a bronchoscope is used to remove the dead tumor tissue. While this often effective for shrinking a tumor, it is not curative. Photofrin usually makes patients likely to develop serious sunburns for about a month after taking it.
- Micro-debriding allows for a tube with a micro-debrider to be inserted into the tumor via a bronchoscope. The debrider "chews" through the tumor to open the trachea.
- Coring a tumor with a rigid bronchoscope to separate tumor tissue from the inner wall of the trachea.
Radiation therapy may be used to treat tumors that:
- Involve more than 50 percent of the trachea.
- Have spread to the lymph nodes or other areas of the chest.
- Be used for patients who are not good surgical candidates.
- Tumors tend to spread for long distances down the trachea but they tend to reoccur at the site of the original tumor. In the case of an adenoid cystic tumor, radiation therapy may be used after surgery.
There are two types of radiation therapies for tracheal tumors, though these tumors are only partly responsive to radiation:
- External–beam radiation which is typically done on a daily outpatient basis over a period of six weeks. The treatment itself only takes a few minutes, the patient usually doesn’t feel anything, but side effects such as malaise may develop.
- Brachytherapy involves the insertion of radiation "seeds." The seeds are temporarily implanted near the tumor to kill it. An outpatient procedure, a bronchoscope passes a tiny catheter through the tumor. The seeds are implanted into this catheter for a few minutes and then the catheter and seeds are removed. The implanted seeds do not penetrate very far from the insertion area so the radiation doses are higher than for external beam radiation. Brachytherapy may also be used after external beam radiation.