Hank Green, the author, vlogger, and YouTube star, revealed that he is battling Hodgkin’s lymphoma, a cancer of the lymphatic system.

Green, who created the YouTube channel Vlogbrothers with his sibling, The Fault in Our Stars and Looking for Alaska author John Green, made the announcement in a video on the channel.

“It’s the most treatable—one of the most treatable cancers,” he said. “It responds very well to treatment. The goal is cure. The procedure to get there is fairly well known, if unpleasant.”

Green published his debut novel, An Absolutely Remarkable Thing, in 2018. In a starred review, a critic for Kirkus called the book “a fun, contemporary adventure that cares about who we are as humans, especially when faced with remarkable events.” A sequel, A Beautifully Foolish Endeavor, followed two years later.

In the video, Green addressed his fans, asking them to sign up for his and his brother’s newsletter and also requesting that they recommend to him “movies and TV shows and video games that are not heavy at all. Like, no emotion.”

On Sunday, he updated his fans on Twitter, writing, “Had a meeting with my oncologist Friday and my PET scan looked very encouraging…Feeling ok! Just really hungover right now, a little nauseous and achey….and I do have the fucking hiccups again!!”

Michael Schaub, a journalist and regular contributor to NPR, lives near Austin, Texas.