When you purchase through links on our site, we may earn an affiliate commission. Here’s how it works. A cancer diagnosis is so difficult. It felt very devastating when Dave called. Dave and [his wife] Melissa called and let us know personally before it went out to the press.

The "Full House" alum revealed Thursday that he wasn't able to shave his head because he's filming a new project soon — and said the criticism "really hurt me."

Dave Coulier is staying positive as he battles a “very aggressive” form of cancer. The “Full House” star, 65, shared an update on his cancer treatment on Friday, posting a photo on his Instagram story giving a thumbs-up during a chemotherapy session.

Dave Coulier tells PEOPLE he is drawing inspiration from the many women in his family who have had cancer as he navigates his own journey with stage 3 non-Hodgkin lymphoma.

"Full House" alum Dave Coulier revealed that he has been diagnosed with cancer, specifically Stage 3 non-Hodgkin lymphoma.

"John knows how to cheer me up and I laughed out loud when he arrived wearing a bald cap — being a true loving friend and brother," Coulier wrote on Instagram

Dave Coulier and John Stamos have a long history. The two spent years filming the beloved series Full House together, but their friendship did not end there. After the 65-year-old revealed he was diagnosed with stage 3 Non-Hodgkin lymphoma,

Earlier this month, the Full House actor - known for playing Joey Gladstone on the sitcom, revealed he had been diagnosed with a "very aggressive" form of non-Hodgkin lymphoma and was undergoing chemotherapy treatments.