Ethan Zohn, 'Survivor' Star, Says His Hodgkin's Lymphoma Has Returned: What Is It?

"Survivor" starEthan Zohnhas announced that his Hodgkin's lymphoma has returned, according to news reports.

Zohn, who won "Survivor: Africa," toldPeoplethat he had been inremission from the cancerfor 20 months until doctors found that it had returned on Sept. 14.

"It's localized in my lung area," Zohn, 37, toldPeople. "But it's good that it'snot all over my body."

Hodgkin's lymphoma, which is a cancer of lymph tissue, is much less common than the other lymphatic cancer, non-Hodgkin's lymphoma, according to the Mayo Clinic.Government datashows that there were 8,830 new cases of Hodgkin's lymphoma last year, and 1,300 deaths from the disease.

The disease is consideredvery curablewhen found early (and can even be curable when it's progressed to a more advanced stage), according to the A.D.A.M. Medical Encyclopedia. More than 90 percent of people with early-stage Hodgkin's lymphoma will go on to live for 10 or more years, and even if the cancer has progressed and spread, 90 percent of those people will go on to live for at least another five years.

There aretwo main types of Hodgkin's lymphoma-- the classical Hodgkin's lymphoma, and the nodular lymphocyte-predominant Hodgkin lymphoma, which is much rarer, according to the National Cancer Institute. Symptoms of the cancer include an enlarged spleen, lymph nodes or other tissues involved in the immune system, as well as weight loss, fever, fatigue and night sweats.

Hodgkin's lymphoma and non-Hodgkin's lymphoma are different in that in Hodgkin's lymphoma, there is thepresence of a cell called the Reed-Sternberg cell, the Mayo Clinic reported. If this kind of cell isn't present, then the cancer is considered non-Hodgkin's lymphoma.

Theexact cause of the disease, formerly known as Hodgkin's disease, is still unknown, the Mayo Clinic reported. But doctors and scientists do know that the cancer occurs when a DNA mutation occurs in one of the body's types of infection-fighting cells. The mutation spurs rapid cell division and gives them the ability to live on when the cells are supposed to die, which results in anaccumulation of these cells, according to the Mayo Clinic.

Hodgkin's lymphoma is most common in people ages 15 to 35 and people over the age of 55. It's also more common in people with afamily history of the disease, as well as men, according to the Mayo Clinic. People who have a weak immune system (whether from disease like HIV/AIDS or from immunosupressing drugs) or people who have been infected with the Epstein-Barr virus also have an increased risk of this kind of cancer.

Treatments for Hodgkin's lymphoma depend on the kind of lymphoma the person has and the severity of the cancer, according to the A.D.A.M. Medical Encyclopedia.Radiation therapy and chemotherapy, alone or together, are typically used to treat this disease, though if they don't work, a bone marrow transplant may also be conducted.

Previously, Zohn had undergone rounds of chemotherapy and astem cell transplantin efforts to beat the cancer. This time around,Peoplereported that Zohn began "smart" chemotherapy in October that targets cancerous cells, and will also undergo another stem cell transplant from one of his family members.

Stem cell transplantsbecome an option for treatment of the disease when chemotherapy doesn't work, according to Fox Chase Cancer Center.

Fox Chase explains how thestem cell method works:

Zohn joins a list of other big names who have been diagnosed with a lymphoma in the past.Paul Allen, co-founder of Microsoft, was diagnosed with non-Hodgkin's lymphoma in 2009, and mohawked actorMr. T-- whose real name is Laurence Tureaud -- was diagnosed with T-cell lymphoma in 1995.

Country music starGene Autrydied in 1988 of lymphoma at age 91 andJoseph Coors Sr., of the Coors beer family, died of lymphatic cancer at 85 in 2003.

This article originally appeared on HuffPost.