Always good-natured, Vicky Phelan began documenting what will be a day filled with nerves in a hospital car park as she queued up for a security car search.
Set to the tune of U2's 'Still Haven't Found What I'm Looking For', the comments section on her Instagram post began to fill immediately with well-wishes from followers all over Ireland.
Phelan took to Instagram on Tuesday to update her followers on her progress as she continues on a medical trial in Maryland.
"OK so today I am back in at the NIH for Round #5 of treatment but I am also having a CT scan today to see where I'm at with treatment - whether it's working, how well it's working...or not!"
The women's health advocate promised to bring her followers along on her journey as much as possible throughout the day.
"I have a very long day ahead so I am going to try to record a few snapshots of my day on Instagram stories throughout the day to give you all an idea of what my typical day looks like... Thank you to everyone for all your support, prayers, candles, messages etc. So, fingers crossed all will go well today, and I'll keep you posted."
Dressed in blue scrubs, she recorded a pre-CT scan video in her American scrubs: "pants and top, no arse hanging out the back."
"So, these are the scrubs you get. And then you just have to pack your stuff into a little bag, and bring them with you."
Getting bloods done, she said "As any cancer patient who has been doing this for years will know....this is always a difficult part of the day because my veins are shot from chemo. I have a port but the phlebotomists (the ppl who take your blood) can't access my port so it can take a while to get a working vein."
Along with the rest of the country, we are holding Vicky in our hearts today.