SMALL CELL (OAT CELL) CANCER OF THE THYMUS

Thymic Small Cell Carcinoma; Small Cell Carcinoma of the Thymus

Small Cell Cancer of the Thymus is a rare aggressive type of cancer in which malignant cancer cells form on the outside surface of the thymus. The thymus is a small organ that is located behind the breast bone (sternum) in the front part of the mediastinum, the space in the chest between the lungs. This type of cancer is among the rarest cancer in humans, comprising of <1% of all adult cancers. The exact cause of this cancer is unknown. These cancers are often associated with autoimmune diseases (i.e. myasthenia gravis, polymyositis, lupus erythematous, rheumatoid arthritis, thyroiditis, Sjogren's syndrome and hypogammaglobulinemia).

Diagnostic testing:

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  Medical history and examination;

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  Imaging tests such as chest x-ray, CT scan and MRI scan;

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  PET scan;

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  Blood tests; or

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  Needle biopsy or surgical biopsy.

Physical findings: The thymus is located near the superior vena cava, the main blood vessel that brings blood from the head and upper body to the heart. Tumors that press on this vessel may cause:

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  Swelling in the face, neck, and upper chest;

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  People may have a bluish color on the upper body;

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  Swelling of the visible veins in the upper body;

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  Headaches; and

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  Reports of dizziness or light-headedness.

ICD-9: 164.0

Small cell cancers of the thymus tend to grow fast and spread (metastasize) to other parts of the body and they have a high risk of recurrence. The prognosis is poor, as it is with all small-cell carcinomas.

This type of cancer is generally treated with surgery to remove the tumor, radiation, and chemotherapy. Chemotherapy may be prescribed prior to surgical resection to shrink the size of the tumor.

SUGGESTED PROGRAMMATIC ASSESSMENT*

Suggested MER for Evaluation:

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  Clinical history and examination that describes the diagnostic features of the impairment; and

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  Pathology report of a biopsy or surgical specimen of the thymus showing small cell histology.

Suggested Listings for Evaluation:

REMARKS

Small Cell Cancer of the Thymus is rare in children.