Dave Coulier has shared an upbeat update from his ongoing cancer battle, giving a thumbs up while undergoing chemotherapy.

“Put a positive spin and send love to all of you fighting and going through chemo,” Full house actor, 65, captioned a photo he shared Instagram stories on 15 Nov.

“And remember to laugh ,” the comedian added at the bottom of the photo, which shows an IV line coming out of the shirt’s neckline.

As Cleveland Clinic explains that a chemotherapy port is often placed in the upper part of the chest and allows for blood draws and the administration of medicine – without needing to prick the skin each time.

Coulier’s post came just two days after the actor exclusively told PEOPLE that he had been diagnosed with stage 3 non-Hodgkin lymphoma – and had started chemotherapy just two weeks after his diagnosis in October.

After he had a respiratory infection, Coulier told PEOPLE that his lymph nodes swelled — prompting his doctor to send him for tests.

“Three days later, my doctors called me back and they said, ‘We wish we had better news for you, but you have non-Hodgkin’s lymphoma and it’s called B-cell and it’s very aggressive,'” he told PEOPLE.

“I went from having a bit of a cold to having cancer, and it was pretty overwhelming,” he said. “This has been a really fast rollercoaster of a journey.”

With non-Hodgkin lymphoma, white blood cells grow abnormally, causing tumors to grow throughout the body, according to Mayo Clinic. Chest pain or fever can also be symptoms — as well as swollen lymph nodes, as Coulier experienced. B-cell lymphoma — the specific type Coulier has — is “rare,” the Mayo Clinic says.

Coulier told PEOPLE that he had already shaved his head as a “preemptive strike,” since chemotherapy is known to cause hair loss.

Coulier says he and his wife Melissa Bring chose to face his diagnosis “head on” – recruiting advice from friends in the medical field.

“We all put our heads together and said, ‘Okay, where are we going?’ And they had a very specific plan for how they were going to deal with this,” he told PEOPLE.

He shared that last week his bone marrow test came back negative — meaning “at that point, my chances of being cured went from something low to 90%. And so it was a great day.”

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