The Wanted star Tom Parker says doctors have confirmed his stage four brain tumour has "significantly reduced" and he is "responding well" to treatment.

The Lightning singer took to Instagram on Thursday to update fans on his progress after receiving his terminal diagnosis of glioblastoma, an aggressive type of brain cancer, last October.

Marking a "good f**king day" after receiving the positive news, Tom vowed to "keep fighting" for the sake of his wife Kelsey Hardwick and their two children.

Alongside a throwback snap of himself, Kelsey and their children Aurelia Rose, 18 months, and newborn Bodhi, he announced: "SIGNIFICANT REDUCTION These are the words I received today and I can't stop saying them over and over again.

"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. Everyday (sic) I'm keeping on the fight to shrink this b**tard," continued the Glad You Came hitmaker.

"I can't thank our wonderful NHS enough. You're all having a tough time out there but we appreciate the work you are all doing on the front line."

Tom also paid tribute to his wife and loved ones for being so supportive during his health battle.

"To my amazing wife @being_kelsey who has literally been my rock," he said. "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.

"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. This journey is a rollercoaster that's for sure. Today is a f**king good day."