Earlier this month, Fonda revealed that she was diagnosed with non-Hodgkin's lymphoma, which she called a "very treatable" cancer. While stopping by PEOPLE and Entertainment Weekly's photo and video studio at the 2022 Toronto International Film Festival on Monday, Tomlin praised her frequent costar and friend as "indomitable."
"She's very forthright and talkative about what's going on with her in all respects," Tomlin, 83, says of Fonda, with whom she costars as lifelong friends in the new movie Moving On. "First thing, she says, 'Don't worry, it's really treatable. It's one of the most treatable forms that you could possibly have, so I'm really lucky in that regard.' "
"And she's like, 'So are you gonna come to my next fundraiser?' " Tomlin says with a laugh. "That's her main objective."
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In her Sept. 2 Instagram post announcing her diagnosis, Fonda, 84, said she had started chemo treatments.
"This is a very treatable cancer. 80% of people survive, so I feel very lucky," she wrote. "I'm also lucky because I have health insurance and access to the best doctors and treatments. I realize, and it's painful, that I am privileged in this. Almost every family in America has had to deal with cancer at one time or another and far too many don't have access to the quality health care I am receiving and this is not right."
She added that she will be doing "chemo for 6 months and am handling the treatments quite well and, believe me, I will not let any of this interfere with my climate activism."
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"Cancer is a teacher and I'm paying attention to the lessons it holds for me. One thing it's shown me already is the importance of community," the Grace and Frankie alum added. "Of growing and deepening one's community so that we are not alone. And the cancer, along with my age — almost 85 — definitely teaches the importance of adapting to new realities."
In a subsequent blog post on her website, Fonda, who's had breast cancer and a mastectomy in the past, said she was "deeply moved and uplifted by all the expressions of love and support" since sharing her health news.
"My heartfelt thanks to all. The messages of love and support mean the world to me," she added.