Diane Keaton, Reese Witherspoon and More Send Jane Fonda Well Wishes amid Cancer Diagnosis

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Hollywood is showing love for Jane Fonda amid her recent cancer diagnosis.

After the Academy Award winner, 84, announced Friday that she's undergoing chemotherapy for non-Hodgkin's lymphoma, she was met with a flood of support and well wishes from a star-studded list of her peers.

"We love you, Jane. You are my hero. You are a warrior. All of my life I have been in awe of all that you do. I will continue to admire the crusader you have always been and always will be," Diane Keaton commented on Fonda's announcement post.

"Sending you all my strength! Love you Jane," wrote Reese Witherspoon. "Sending you healing light, love and strength," Debra Messing commented. "Love you, Jane. Thinking of you, always," Chelsea Handler wrote.

"GRACEFUL QUEEN. @janefonda thank you, even at this difficult time you are sharing with [us]. It's so important to have a positive mindset!! And you do, GOD BLESS [you]!! My thoughts and prayers are with you.." wrote Naomi Campbell.

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Mark Ruffalo commented: "Sending you all the love and strength, Jane. Always full of grace and optimism."

"Sending you so much love and light and all the positive thoughts possible. How beautifully said and strong you are," wrote Lily Collins.

"You are a warrior. This shall pass. Sending all of my love and healing energy. God is with you," Lenny Kravitz wrote.

"Sending you so much love, Jane. You got this. And we're so grateful and lucky to have you. Resist!" Rosario Dawson commented.

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"And as always teaching us all how to be graceful and purposeful. So powerful dear Jane in everything you do. Sending strength," wrote Naomi Watts.

"Handling this with grace, intelligence and selflessness, as always. Holding you in our hearts," commented Katie Couric.

"Sending much love, Jane. Beast it," Rachel Brosnahan wrote. "Beloved we love you!!!" Andie Macdowell commented. "Lean on us; we love you Jane," wrote Frances Fisher.

Alyssa Milano wrote: "Wishing you more strength than you need and more love than you can bear. Call me if you need anything. Always here. Always."

"You amaze me, always. Sending all the healing energy I can muster," wrote Ross Mathews.

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Fonda appeared optimistic as she revealed her diagnosis to 1.9 million Instagram followers.

"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."

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."

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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. 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.