Mesothelioma & Breast Cancer

This article was written by a friend, hope it sheds some light on a very real issue.

Is there a link between breast cancer and mesothelioma? One is a common cancer in women, and the other is rare and caused by asbestos exposure, usually in men. Researchers are finding similarities between the two, and further studies are underway.  The connection between asbestos and mesothelioma is already clear, but scientists say asbestos might contribute to cancer of the breast, digestive system, reproductive, and lymph systems.

What is mesothelioma?

Mesothelioma is an incurable cancer that starts in the mesothelium, the tissue that covers internal organs. There are four kinds of mesothelioma: 

  • pleural which affects the lining of the lungs

  • peritoneal which affects the lining of the abdomen

  • pericardial which affects the heart 

  • testicular

Pleural mesothelioma, the most common form, causes breathing problems, chest pain, coughing, and unexplained weight loss. Symptoms may take from 20 to 50 years to develop, and the risk after exposure never goes away. 

How is breast cancer linked to mesothelioma?

Studies done on breast cancer and asbestos have been inconclusive, but a few suggest a link. In one United Kingdom study, women who lived near an asbestos manufacturing plant had a slightly higher chance of getting breast cancer.  Other research in Great Britain also found that women who had asbestos fibers in their lungs from past exposure were more likely to develop breast cancer. In 2009, however, an Australian study looked at over 3,000 women who lived in a town that had an asbestos plant until 1966. Compared to the general population, the women were more likely to get ovarian or cervical cancer, but their rate of breast cancer didn't go up.

Researches know asbestos enters the lungs when people inhale the fibers, but they don’t know if the fibers can spread to the chest cavity and breast through the lymphatic system. They are also uncertain if shards of asbestos can travel to the wall of the chest through the pleural tissue or lungs and cause cancer. 

What do researchers know about mesothelioma and breast cancer?

One factor that makes mesothelioma hard to diagnose is its similarity to other kinds of cancer. Although rare, at least one case of metastatic mesothelioma was mistaken for breast cancer. Symptoms of breast cancer may result from cancer in the mesothelium. Because markers, structure, and cell growth can be similar in both diseases, the origin of the cancer can be hard to establish.

Although rare, there have been incidents where high-energy radiation used to shrink tumors in breast tissue led to mesothelioma. Radiation used to treat breast cancer passes through the skin and pleural cavity, and it can occasionally cause changes that lead to cancer. 

Researchers who discovered that mesothelioma could be mistaken for breast cancer wondered if breast cancer treatment would also help mesothelioma. Treatment with a drug called aromasin reduces estrogen and slows the growth of tumors in breast cancer. When given to mice with mesothelioma, it slowed the spread of cancer cells and reduced the size of tumors. This could be because cells in the two diseases are similar. 

Pliny the Elder wrote about the dangers of asbestos in ancient Rome, but the toxin's link to mesothelioma was unknown until the 20th century. Although the government has taken steps to limit the use of asbestos since the 1970s, the Trump administration is trying to ease those restrictions. Americans need to stand up for environmental safety and medical research if diseases like breast cancer and mesothelioma are to be eliminated.

Posted on September 16, 2019 .