Transcript for Jeff Bridges reveals lymphoma diagnosis
We move to our "Gma" cover story. Jeff bridges and his announcement he's been diagnosed with lymphoma. Will reeve has the story. Reporter: This morning, beloved actor Jeff bridges with a stunning announcement Monday evening revealing he's been diagnosed with lymphoma. channeling his best known character bridges tweeting, quote, as the dude would say, expletive has come to light. I feel fortunate I have a great team of doctors and the prognosis is good. I'm starting treatment and will keep you posted on my recovery. This aggression will not stand, man. Reporter: The 70-year-old actor has had one of the most stoied careers in cinema. Seven-time Oscar nominee bridges won best actor for his portrayal of an alcoholic singer in 2009's "Crazy heart." Among so many others, his turn as the dude in 1998's "The big lebowski" is one of the most iconic performances of all time. Nobody calls me lebowski. You got the wrong guy. I'm the dude, man. Reporter: Lymphoma, a type of blood cancer that develops in the lymphatic system part of the body's disease-fighting network can affect patients of any age. Nearly 800,000 Americans are living with or in remission from lymphoma and over 85,000 new cases are expected to be diagnosed this year. For "Good morning America," I'm will reeve, ABC news, New York. Okay, will, thanks very much. Let's bring in Dr. Jen Ashton for more. What more do we know about lymphoma, Jen? Well, George this, is one of the so-called liquid tumors or cancers that affect the blood and the lymph system is part of our immune system so glands and organs like the thymus, spleen, bone marrow, lymph nodes and according to the national cancer institute lymphoma will affect approximately 2 out of 100 people in their lifetime. Who is most at risk? How is it diagnosed? Well, there are different types of lymphoma, but Hodgkin lymphoma which is one of the more common types tends to affect men more than women, tends to affect white men in particular and can affect two age groups, teens and then people older over the age of 75. In terms of the symptoms, really the classic one, things like swollen lymph nodes in the neck, in the armpits and in the groin, night sweat, fever and unexplained weight loss and we usually make the diagnosis with a combination of blood tests, biopsy and some imaging tests like C.A.T. Scan. How is it treated? You know, the hallmark really with any cancer is it depends on the stage and the type but chemotherapy, radiation therapy and a lot of excitement and optimism for treating lymphoma with immune therapies so cells that fight the tumor that are reprogrammed, re-engineered and then infused back into the patient but, George, any time we see a celebrity coming forward with their health battle, it does so much to increase awareness. And we are all wishing Jeff bridges well, Jen, thanks very much.
This transcript has been automatically generated and may not be 100% accurate.