A 21-year-old medical student has turned to photographic fun to bring some cheer to others during her chemotherapy.

Tessa Calder, a fourth-year student at the University of New South Wales, has entertained hundreds of friends over the past six months with a series of posed photos featuring her newest companion — an IV pole.

You shall not pass: Gandalf with her IV pole staff. ( Supplied: Tessa Calder )

Ms Calder was diagnosed with brain cancer in April this year.

"I started to get a bit of back pain and I thought it might have been my new bed, but then I started to vomit a lot and had these tingly feelings in my feet so I went to the doctor," she said.

"I was working at a medical centre at the time and they were fantastic, the whole team were. They sent me straight away for a scan.

"I was diagnosed with a metastatic medulloblastoma — basically a tumour in my cerebellum, the back part of my brain. But the reason I was getting all this back pain was that it had spread so there were all these deposits down my spine."

Ms Calder went straight into surgery to remove the tumour and then had six weeks of radiotherapy. It was during some down time in her first round of chemotherapy that she decided to strike a funny pose with her IV pole.

"I had a window and you could sort of look up to the second floor where it was just like a glass corridor – and these patients would walk by in their white hospital gowns with their IV poles and Dad was just trying to make me laugh: 'Oh look, Tessa, there's the Pope! There he is again, there's so many popes!'," she said.

"I had time on my hands so I got some paper and made a pope hat and I think people thought I was absolutely ridiculous – I got some very weird looks!"

Ms Calder shared the photo to Facebook with a caption that said:

"Everybody meet Francis, the IV pole. We're joined at the hip (well actually the chest to be anatomically correct) and he's very pope-ly. I know that word should probably be papal but pope-ly just sounds so much better. Disclaimer: does not include bullet-proof vehicle. But Francis is very mobile (see what I did there?)"

The first funny photo saw Ms Calder transform into Pope Francis. ( Supplied: Tessa Calder )

That first photo attracted hundreds of likes and comments from friends encouraging Ms Calder to share more photos of her adventures with 'Francis'.

Since then, she has transformed her medication and apparatus into Gandalf's staff, Harry Potter's broomstick and a set of beer taps for Oktoberfest.

"My roommate was going through some tough times so I showed her the photos and it kind of cheered me up as well, it was just something to do," Ms Calder said.

"If it brought a smile to someone's face, even if they're not sick ... I think the more positive and light-hearted things on social media the better."

Ms Calder said her friends and family had enjoyed joining in on the fun.

"It's just been great because my friends have been visiting and we talk about these things and then get an idea going and one of them will say 'oh I've got a hat I can bring in' or just you know, little bits and pieces," she said.

"My friends and family really have been the best medicine. They've stuck by me and it's been tough for them too, but they make me laugh and smile and forget about the yucky stuff."

One of Ms Calder's friends is even taking on a charity bike ride from Rutherglen in north-east Victoria to Sydney to raise funds for the Cure Brain Cancer and NELUNE Foundations.

The Cure Brain Cancer Foundation is the peak organisation for brain cancer research while NEULENE is a not-for-profit charity that provides emotional support, care and post-operative medical aid to children, adolescents, adults and their families.

Ms Calder says her friends have enjoyed being part of the photo shoot fun. ( Supplied: Tessa Calder )

As well as putting a smile on her friends' faces, Ms Calder said the photo shoots gave her something positive to focus on during the unpleasant treatment.

"It's so nice to be asked 'how are you going?' but sometimes you also want to have a laugh and be a bit normal and not talk about vomiting and all that stuff," she said.

"It's hard sometimes. I'm not going to lie, you can't always laugh about it and sometimes it just sucks.

"But in a way ... you've got to laugh at yourself, in any challenge."