Jane Fonda, 84, Diagnosed with 'Very Treatable' Cancer and Is Undergoing Chemo: 'I Feel Very Lucky'

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Jane Fonda has been diagnosed with cancer.

The Academy Award winner, 84, appeared optimistic as she revealed Friday on Instagram that she has non-Hodgkin's lymphoma, noting that she's begun chemotherapy.

"So, my dear friends, I have something personal I want to share. I've been diagnosed with non-Hodgkin's lymphoma and have started chemo treatments," Fonda began in the post. "This is a very treatable cancer. 80% of people survive, so I feel very lucky."

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She explained that she's been undergoing chemo for six months, and is "handling the treatments quite well," adding that she "will not let any of this interfere with my climate activism." Fonda revealed the news on Fire Drill Friday, a demonstration to raise awareness about climate change that she leads every week.

"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. 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," Fonda added.

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Fonda also acknowledged that she is "privileged" in being able to afford quality healthcare when many others can't, while using her diagnosis as a call-to-action during "the most consequential time in human history."

"I will not allow cancer to keep me from doing all I can," she wrote. "Using every tool in my toolbox and that very much includes continuing to build this Fire Drill Fridays community and finding new ways to use our collective strength to make change.

"The midterms are looming, and they are beyond consequential so you can count on me to be right there together with you as we grow our army of climate champions," Fonda concluded.

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The Grace and Frankie star previously discussed facing her own mortality during an interview on CBS Sunday Morning. "I'm super-conscious that I'm closer to death. And it doesn't really bother me that much," she said in April.

"What bothers me is that my body is, you know basically not mine! My knees are not mine, my hips are not mine, my shoulder's not mine. You're looking at somebody who's only me from here up."

"The fact is if you're alive and relatively healthy at an older — I mean, I'm almost 85. The fact that I'm still alive and working, wow, who cares if I don't have my old joints? And I can't ski or bike or run anymore? Enh. You know, you can be really old at 60, and you can be really young at 85. Health!" Fonda added.