Pancoast tumors form at the very top of either lung. Pancoast tumors are a subset of non-small cell lung cancers that invade the top of the chest. Because of their location, they invade adjoining tissue.
Pancoast tumors form an abnormal patch of tissue over the lung apex and principally involve the chest wall structures rather than the underlying lung tissue. They may invade areas such as lymph nodes, nerves, ribs, and spine.
The risk factors for almost all lung cancers are similar. These include the following:
Secondary smoke exposure
Prolonged asbestos exposure
Exposure to industrial elements (such as gold or nickel)
Pancoast Tumor Symptoms
Although a Pancoast tumor is a lung tumor, it rarely causes symptoms that are typically related to the lungs (like cough or chest pain).
The initial symptom is usually pain in the shoulder, the inner part of the shoulder blades, or both.
The pain may later extend to the inner side of the arm, the elbow, and the pinky and ring fingers.
The associated pain is severe and constant, often requiring narcotic pain medications for relief. The affected person usually needs to support the elbow of the affected arm in the opposite hand to ease the tension on the shoulder and upper arm.
The hand, arm, and forearm may weaken, muscles degenerate or shrink from disuse, or develop a sensation of pricking, tingling, or creeping on the skin.
If the tumor extends to the certain nerves, Horner syndrome may develop on one side of the face. Horner syndrome is characterized by a drooping eyelid, absence of sweating on the affected side of the face, and narrowing of the pupil.
In up to 25% of people with a Pancoast tumor, compression of the spinal cord and paralysis of the lower half of the body develop when the tumor extends into the opening between two vertebrae.
Pancoast Tumor Exams and Tests
Exams and tests that may be used to diagnose a Pancoast tumor include:
In the early stages, Pancoast tumors are difficult to detect on chest X-rays because the top of the lung is located in an area of the body that is difficult to visualize clearly on an X-ray. Shadows that lie over the lungs make the image on the X-ray film unclear. Many patients end up consulting orthopedic surgeons and/or neurologists before a definitive diagnosis is made.
A chest X-ray may reveal anything from asymmetry of the top of the lungs in the form of a small, uniform patch of tissue on the apex of one lung to a large mass, depending on the stage when the tumor is first diagnosed.
The plain chest X-ray may show that the tumor has invaded one or more ribs or parts of the vertebrae. Bone destruction of the back ribs may be visible on the X-ray.