Pancoast tumour

Pancoast tumour overview

Pancoast tumours are cancers named after an American doctor called Professor Henry Pancoast in the 1930s. They are tumours that form at the extreme apex (very top) of either the right or left lung in the superior sulcus (a shallow furrow on the surface of the lung). Pancoast tumours are a subset of lung cancers that invade the top of the chest wall. Because of their location in the apex of the lung, they invade adjoining tissue.

Pancoast tumours originate at the top margin of the lung. They form an abnormal patch of tissue over the lung apex and principally involve the chest wall structures rather than the underlying lung tissue. They invade the following structures:

• Lymphatics (small, thin vessels that carry lymph fluid through the body)
• Lower roots of the brachial plexus (a complex network of nerves that is formed chiefly by the lower four cervical [neck] nerves and the first thoracic [chest] nerve)
• Intercostal nerves (nerves that lie between a pair of adjacent ribs)
• Stellate ganglion (a mass of nerve tissue containing nerve cells that form an enlargement on a nerve or on two or more nerves at their point of junction or separation)
• Sympathetic chain (either of the pair of ganglionated lengthwise cords of the sympathetic nervous system that are situated on each side of the spinal column)
• Adjacent ribs
• Vertebrae.
• Carcinomas (cancerous tumours) in the superior pulmonary sulcus produce the Pancoast syndrome, which is characterised by pain in the shoulder and along the inner side of the arm and hand. Pancoast tumours tend to spread to the tissue surrounding them in the early stage of the disease. As long as the cancer has not metastasised (spread) and involved the regional lymph nodes (small, bean-shaped structures found throughout the body), these tumours can be successfully treated.

Pancoast tumour causes

The risk factors for almost all lung cancers are similar. These include the following:

• Smoking
• Secondary smoke exposure
• Prolonged asbestos exposure

Exposure to industrial elements (e.g. gold, nickel).

Pancoast tumour symptoms

Although a Pancoast tumour is a lung tumour, it rarely causes symptoms that are typically related to the lungs (e.g. cough, chest pain).

The initial symptom is pain in the shoulder, inner part of the scapula (large, triangular, flattened bone that lies over the ribs on the back), or both.

The pain may later extend to the inner side of the arm, elbow and the little 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, atrophy (degenerate or shrink from disuse) or develop paraesthesia (a sensation of pricking, tingling or creeping on the skin).

If the tumour extends to the sympathetic chain (a series of ganglia [masses of nerve cells] that run parallel to the vertebrae) and stellate ganglion, Horner syndrome may develop on the face and hand of one side of the body. Horner syndrome is characterised by drooping eyelids (ptosis), absence of sweating (anhidrosis), sinking of the eyeball (enophthalmos), and excessive smallness or contraction of the pupil of the eye (miosis).

In as many as 10%-25% of people with Pancoast tumour, compression of the spinal cord and paraplegia (paralysis of the lower half of the body with involvement of both legs) develop when the tumour extends into the intervertebral foramina (opening between two vertebrae).