Rare Forms of Cancer See Dramatic Increase over Last Decade - Mesothelioma and Thyroid Cancer

Thanks to significant advances in medical technology, cancer rates have declined significantly in recent years. In fact, according to a study conducted by the National Cancer Institute, the overall rate of cancer incidence has declined an average of 1% per year over the last several decades.

However, in stark contrast to the general decline in cancer rates, several types of cancer have seen a dramatic increase during the same period such as thyroid cancer and mesothelioma. Some of the cancers that have undergone an inexplicable increase in incidence have been rare forms of the disease that were once little-known and rarely diagnosed.

Mesothelioma and Thyroid Cancer

This week, we'll take a look at mesothelioma and thyroid cancer, both once relatively rare forms of the disease that have bucked the overall trend in declining cancer rates, instead beginning to be diagnosed more frequently now than they were in the past.

What is Mesothelioma?

This rare form of cancer is often related to exposure to the insulating material asbestos, which was widely used in both residential and commercial construction until the late 1970s. Although mesothelioma has been known to occur in patients who have not been exposed to asbestos, it is much more common among people who have histories of high-level asbestos exposure, often as a result of their occupations.

The most common form of mesothelioma is known as malignant pleural mesothelioma, which accounts for almost 70% of all known cases of this form of cancer. Malignant pleural mesothelioma is a cancer that attacks the cells in the pleura, which is the medical term for the special tissue that forms the lining of the lungs and the chest cavity.

Asbestos-related cases of malignant pleural mesothelioma occur when the small fibers travel into the small passageways leading into and out of the lungs, as well as the pleural tissue. Over time, the presence of the asbestos sets off a series of chemical reactions, the exact nature of which scientists have not yet been able to determine. These reactions spark cancerous cell growth in the area, causing the cells in the region to grow abnormally.

This abnormal cell growth, in turn, can result in the thickening of the pleural tissue and, eventually, to the accumulation of excess fluid in the region. The consequences of the thickening and fluid accumulation are the painful symptoms that are most closely related to malignant pleural mesothelioma, namely, respiratory difficulty, shortness of breath, chest pain, and intense pressure.

Over the course of the last decade, malignant pleural mesothelioma has been one of the only types of rare cancers to actually see an increase in diagnosis rates. Although the exact causes of this alarming trend have not yet been definitively identified, scientists believe that it may be due to the peak in asbestos-related exposures several decades ago.

What is Thyroid Cancer?

The often-overlooked thyroid gland is a small, butterfly-shaped organ that is located at the base of the neck. When the thyroid gland is functioning properly, it rarely figures in the way we assess our own health or well-being. However, when thyroid function goes awry, it can significantly impede the body's ability to function. This is due to the fact that the tiny thyroid gland plays a major role in regulating the production and distribution of hormones within the body.

Cancer of the thyroid occurs when malignant abnormal cell growth is seen in or around the thyroid gland. Malignancy is a key factor in diagnosing thyroid cancer, because non-cancerous abnormal cell growth often results in thyroid nodules, which are an entirely different type of disorder.

Overall rates of thyroid cancers have seen an alarming spike over the last decade. According to public health data, the rate of thyroid cancer diagnosis almost doubled in some parts of the United States between 1990 and 2000. In fact, diagnoses of thyroid cancer are now outpacing many other types of the disease that were once thought to be far more common.

Scientists around the world are working to unravel the mystery of thyroid cancer's rapid rise. Some have theorized that environmental factors such as radiation, pollutants, or toxins may be to blame for the trend. Others have argued that the increase in the number of thyroid cancer cases is a result of more sophisticated medical technology that allows for earlier and more reliable diagnosis of the disease.

As with all forms of cancer, the earlier a diagnosis can be made, the better the outlook for the patient. If you have concerns about malignant pleural mesothelioma or thyroid cancer, talk to your doctor for a personalized risk profile. Be sure to mention any history of exposure to radiation or asbestos. Don't forget to check back each week for more of the medical news you need!

For Further Reading

• http://www.cancer.gov/cancertopics/types/thyroid

• http://www.ncbi.nlm.nih.gov/books/bv.fcgi?indexed=google&rid=inserm2.section.665

• http://www.cancer.gov/cancertopics/factsheet/Sites-Types/mesothelioma