Thoracic Cancers
Thoracic
cancers include breast cancer, bronchial adenomas, bronchial
carcinoid tumors, pleuropulmonary blastoma, esophageal tumors,
thymomas, tumors of the heart, and mesothelioma. These thoracic
cancers are discussed below.
Breast Cancer
Most
tumors that involve the breast during childhood are benign (noncancerous)
fibroadenomas that can be watched for change without the need for
biopsy. Rarely, such breast tumors will show malignant change with
sudden, rapid growth. These are called phyllodes tumors, and require
biopsy or surgical removal without mastectomy. Other types of breast
cancer have been reported in both males and females younger than 21
years. There is an increased lifetime risk of breast cancer in
patients who were treated for any cancer with radiation therapy to
the chest area, including female survivors of Hodgkin’s lymphoma.
Mammograms should start at age 25 or 10 years after radiation
therapy to the chest, whichever came last. Treatment options include
radiation, chemotherapy, and surgery for children and adolescents
with breast cancer. Breast tumors may also occur as cancers that
have spread from other types of cancer such as leukemia,
rhabdomyosarcoma, other sarcomas, or lymphoma, particularly in
patients infected with the human immunodeficiency virus (HIV).
Bronchial Tumors
Bronchial
tumors (which are slow-growing cancers in the trachea or large
bronchi, the large airways of the lung), are most often carcinoid
tumors in children. Symptoms include cough and spitting up blood,
and can sometimes be confused with asthma symptoms like wheezing,
resulting in delayed diagnosis. Primary treatment is surgery to
remove the tumor and lymph nodes and vessels where cancer may spread.
The prognosis for most bronchial tumors in children is excellent,
even when the cancer has spread to nearby areas. Rarely, carcinoid
tumors develop as aggressive(fast-growing) cancers that are more
likely to spread to other areas of the body by the time they are
diagnosed. For bronchial carcinoid tumors, neither chemotherapy nor
radiation therapy is indicated, unless evidence of metastasis (spread
of cancer to other areas of the body) is documented.
Pleuropulmonary
Blastoma
Pleuropulmonary blastomas are rare tumors that usually occur under
the tissue covering the lungs. The tumors may recur or spread, in
spite of surgical removal. Responses to chemotherapy have been
reported. Radiation may be used when the tumor cannot be surgically
removed. A family history of cancer in close relatives has been
noted for many young patients affected by this tumor.
Esophageal Tumors
Cancer of
the esophagus (the muscular tube through which food passes from the
throat to the stomach) is rare in the pediatric age group. Symptoms
are related to difficulty in swallowing, and associated weight loss.
Treatment options for esophageal cancer include either radiation
therapy or chemotherapy. Prognosis generally is poor for this
cancer, which rarely can be completely removed by surgery.
Thymomas and
Thymic Carcinoma
A cancer
of the thymus (an organ in the chest, behind the breastbone) is not
considered a thymoma (cancer) or a thymic carcinoma unless there are
cancerous changes of the epithelial cells that cover the organ. The
term thymoma usually describes cancers that do not have obvious
changes in the epithelial cells. Thymic carcinoma has clear-cut
changes of the epithelial cells. Other tumors that involve the
thymus gland include lymphoma (cancer that arises in cells of the
lymphatic system) and germ cell tumors (tumors that begin in cells
that give rise to sperm or eggs); these tumors are not true thymomas
or thymic carcinomas.
Thymomas
and thymic carcinomas are rare in adults as well as children.
Various diseases and syndromes are associated with thymomas,
including myasthenia gravis, polymyositis, systemic lupus
erythematosus, rheumatoid arthritis, thyroiditis, and pure red cell
aplasia. Endocrine (hormonal) disorders such as hyperthyroidism,
Addison’s disease, and panhypopituitarism can also be associated
with a diagnosis of thymoma or thymic carcinoma.
Cancer of
the thymus may be caused by a specific chromosome change. Every cell
in the body contains DNA (genetic material stored inside chromosomes)
that determines how the cell looks and acts. Cancer may develop when
part of the DNA from chromosome 15 moves to another chromosome, or
when chromosome 15 is broken. This type of cancer may appear in the
thymus or in other places along the midline of the body, including
parts of the airway, the area between the lungs, and the bladder. It
usually cannot be cured.
Thymomas
and thymic carcinomas are usually located in the front part of the
chest and are usually discovered during a routine chest x-ray.
Symptoms can include cough, difficulty with swallowing, tightness of
the chest, chest pain, and shortness of breath, although nonspecific
symptoms may occur. These tumors generally are slow growing but are
potentially invasive, with cancer spreading to distant organs or
lymph nodes. Surgery is performed with the goal of a complete
removal. Radiation therapy is necessary for patients with invasive
thymoma or thymic carcinoma, whether or not there has been surgery.
Chemotherapy is usually reserved for patients with advanced-stage
disease who have not responded to radiation therapy or steroids. The
prognosis for patients with invasive thymoma or thymic carcinoma
usually is poor, although significantly higher survival rates have
been reported for patients with tumors that have not spread to the
surrounding areas.
Tumors of the
Heart
Primary
tumors of the heart may include benign (noncancerous) and malignant
(cancerous) teratoma (a tumor made up of a mixture of tissues),
rhabdomyosarcoma (a tumor of muscle tissue), hemangioma (a usually
benign tumor made up of blood vessels), and chondrosarcoma (a type
of cancer that forms in cartilage). Symptoms include abnormalities
of heart rhythm, enlargement of the heart, fluid in the pericardial
sac, and congestive heart failure. Successful treatment requires
surgery (which may include transplantation) and chemotherapy
appropriate for the type of cancer that is present. Benign tumors of
heart muscle (rhabdomyomas) usually shrink and go away on their own.
Mesothelioma
Mesothelioma, an extremely rare cancer in children, can involve the
tissue coverings of the lung, the heart, or the abdominal organs.
These tumors can spread over the surface of organs, without invading
far into the underlying tissue, and may spread to nearby or distant
lymph nodes. Mesothelioma may develop after successful treatment of
an earlier cancer, especially after treatment with radiation. In
adults, these tumors have been associated with exposure to asbestos,
which was used as building insulation. The amount of exposure
required to develop cancer is unknown, and there is no information
about the risk of children exposed to asbestos.