Her non-Hodgkin's lymphoma diagnosis was announced on September 2 via Instagram.

Fonda wrote, "I want to share something personal with you.".

The chemo has started for my non-Hodgkin's lymphoma.

A very treatable cancer. The survival rate is 80%, so I feel lucky."

Despite the treatments, she says she will continue her advocacy efforts.

Adding, "I won't let this interfere with my climate activism," she wrote, "I'm doing chemo for six months.".

Health insurance and access to the best doctors make me lucky.

Also, people need to know that fossil fuels cause cancer, so we can eliminate them.

In the run-up to the midterm elections, the Academy Award-winner referred to cancer as a "teacher."

I am paying attention to what cancer is teaching me," Fonda wrote.