In this March 17, 2010 file photo, then PayPal president Scott Thompson speaks at the company's international headquarters in Singapore. (Wong Maye-E/Associated Press)

Scott Thompson’s health reportedly contributed to his decision to step down as Yahoo chief executive over the weekend. Thompson has been under fire lately for citing a false degree in computer science on his biography.

A report from The Wall Street Journal says that Thompson has started treatment for thyroid cancer, that he did not want his illness made public, and that may also have contributed to his decision to step down. Yahoo’s head of global media, Ross Levinsohn, replaced Thompson as interim CEO on Sunday.

The unnamed sources in the Journal’s report did not go into further detail about what kind of thyroid cancer Thompson may have.

Thyroid cancer is not that common in the United States, according to a fact sheet from The Mayo Clinic, but rates seem to be increasing in the United States as doctors get better at detecting symptoms of the disease. Most cases of thyroid cancer can be cured with treatment, the site said.

There are several types of thyroid cancer, and most can be treated effectively with surgery or radiation therapy. As the cancer develops, symptoms can include a lump on the front of the neck, difficulty in speaking, difficulty in swallowing and swollen lymph nodes.

One kind of thyroid cancer, anaplastic carcinoma is a much more virulent form of the cancer believed to have claimed the life of Chief Justice William Rehnquist. Those suffering from anaplastic carcinoma, which is rare, have a very low chance for survival, often less than six months, The Washington Post reported.

The vast majority of thyroid cancer cases have a 5-year survival rate of near 100 percent if caught early, according to the American Cancer Society.

For more information on thyroid cancer, visit the American Cancer Society or the Thyroid Cancer Survivors’ Association Web sites.

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