Last reviewed by Dr. Raj MD on January 12th, 2022.
What is Pancoast Tumor?
Pancoast tumor is a malignant neoplasm of the lungs particularly at the very apex of the lung either on the right or on the left exactly on the superior sulcus. Pancoast tumor is also referred to as pulmonary sulcus or superior sulcus tumor and is mostly non-small cell cancer.
Pancoast tumor primarily invades the structure of the chest wall including the adjoining tissues. The tumor can basically invade the adjoining structures such as the lymphatic, intercostal nerves, and brachial plexus at its lower roots, sympathetic chain, stellate ganglion, vertebrae and the nearby ribs.
Pancoast tumor is a type of lung cancer although the incidence is much less common than the other type of non-small cell lung cancer. The disease used to be regarded as incurable and fatal but modern methods of therapies combined with the developed new techniques of resection has brought improvements bringing the disease as curable. The prognosis of Pancoast tumor however depends on the stage of the cancer by the time of its diagnosis.
Pancoast Tumor Symptoms
Although a type of lung cancer, Pancoast tumor seldom manifests with symptoms that are related to the lungs such as coughing or chest pain. The symptoms of Pancoast tumor are mostly due to the involvement of the adjacent tissues which are being compressed as the tumor is gradually enlarging in size. The growth of the malignant neoplasm results of destructive lesions in the thoracic inlet and also involving the brachial plexus and the stellate ganglion leading to the following common presentation of Pancoast tumor:
- Perception of pain along the shoulder and the inner portion of the scapula which usually radiate towards the axilla, scapula, muscles of the hand and down towards the fingers particularly the pinky and the ring finger
- The pain is usually severe and constant which may require the patient to take narcotic pain reliever
- Weakening and atrophy of the muscle of the hand and arms often due to disuse
- A tingling sensation or pricking sensation may also occur
- Horner syndrome may develop when the tumor extends to the stellate ganglion. The syndrome is characterized by drooping eyelids, enophthalmos and miosis or the excessive contraction of the pupil of the eye. Anhidrosis or the absence of sweating is also included in Horner syndrome that may manifest in patient with Pancoast tumor
- Sudden and unexplainable weight loss is also common among patients
- Spinal cord compression and paraplegia may also occur if the tumor extends down to the intervertebral foramina
- Edema may also occur if blood vessel compression is present
Pancoast Tumor Causes
Pancoast tumor is a type of lung cancer and is mostly caused by non-small cell lung cancer. The exact cause of the disease just like any other form of cancer remains vague although several risk factors are believed to contribute to the incidence of the disease.
The risk factors for Pancoast tumor are similar to the risk factors for developing lung cancer and such are:
Smoking cigarette is primarily implicated in the cause of Pancoast tumor. The risk for the development of the disease depends on the smoking history of an individual where a greater number of smoking histories have a greater risk for developing a Pancoast tumor.
Passive smoking or second-hand smokers also have a risk for developing a Pancoast tumor. The degree of risk depends on the number of years of exposure.
Asbestos exposure is also considered a risk factor for developing a Pancoast tumor. The silicate fibers contained in asbestos can get into the lung tissue after a prolonged period of exposure. This is usually true in individuals working in industries that use asbestos.
Family history of lung cancer is considered to contribute to the development of Pancoast tumor and any other type of lung cancer.
Imaging tests are the usual method in diagnosing Pancoast tumor while blood tests are usually non-specific. The diagnosis for Pancoast tumor is often impeded by the absence of typical lung cancer symptoms and the manifestation of symptoms that are somewhat similar to other orthopedic condition.
Diagnostic methods for Pancoast tumor include the following:
Plain film or chest X-ray will reveal opacity of soft tissue at the very apex of the lung. A tumor extending to the supraclavicular fossa and the involvement of the ribs are occasionally revealed in plain films.
Ultrasound is only helpful in guiding percutaneous biopsy therefore limiting its use in diagnosing Pancoast tumor.
CT scan is used only for identifying bone involvement and does not actually diagnose the Pancoast tumor.
Magnetic resonance imaging is the more accurate among the imaging tests for Pancoast tumor. It is best used for identifying tumor at the superior sulcus with its exceptional revelation of soft tissue involvement.
The treatment of Pancoast tumor depends on the stage of the disease by the time it was first diagnosed. The close distance of the tumor with the vital organs makes it more difficult in performing surgical resection. The stage of the tumor indicates the need of the patient to undergo irradiation prior to the surgery.
Pancoast tumor patients are usually treated with a combination of chemotherapy and radiation therapy prior to surgical resection. The aim of the neoadjuvant treatment is to reduce the size of cancer prior to radical treatment intervention. Palliative therapy is given when cure is no longer possible.
Survival Rate of Pancoast Tumor
Pancoast tumor is no longer considered incurable as modern methods of therapeutic approach has improved the survival rate for most of Pancoast tumor patients. The 5-year survival rate however, depends on early diagnosis or the stage of the cancer by the time it was diagnosed.
The overall 5-year survival rate on the other hand remains poor despite the modern therapeutic approach while the survival rate depends on the completeness of surgical resection. A complete resection usually gives about 45% of 5-year survival rate while an incomplete resection results in a 0 percentage of 5-year survival rate.