The British singer, 32, a member of The Wanted, announced in October that he'd been diagnosed with a grade four brain tumor and said he was "undergoing treatment."
Good news came for the singer Thursday when he spoke with a medical professional after undergoing an MRI earlier in the week.
To share an update, the star posted a photo of himself smiling with his wife and children.
"SIGNIFICANT REDUCTION," began the gleeful caption of the photo. "These are the words I received today and I can’t stop saying them over and over again."
The Wanted’s Tom Parker said that his brain tumor has seen ‘significant reduction.’ (Photo by Desiree Navarro/WireImage)
"I had an MRI scan on Tuesday and my results today were a significant reduction to the tumour and I am responding well to treatment," Parker announced. "Everyday I’m keeping on the fight to shrink this bastard!"
He then thanked Britain's National Health Service employees for their work both in helping him combat his ailment and "on the front line" of the coronavirus pandemic.
"To my amazing wife @being_kelsey who has literally been my rock. My babies- I fight for you every second of every day. Friends, family and everyone on this journey with me- you have got me through my darkest days," he added.
Parker then spoke directly to his followers and fans: "To everyone on here- your love, light and positivity have inspired me. Every message has not been unnoticed they have given me so much strength."
Tom Parker is fighting a grade four brain tumor. (Getty Images)
To conclude the post, Parker pointed out that he's on a "rollercoaster" of a journey, but felt that "today is a f—ing day."
In an interview with OK! magazine, Parker said he was diagnosed with glioblastoma after a seizure sent him to a hospital.
He also said that they chose not to ask about a timeline of survival for the inoperable cancerous cells.