Taking to his Instagram page on Thursday, the 32-year-old singer shared a beautiful family photo as he gave fans a positive update on his progress.
WATCH: Tom Parker stars in fun video with his family
"SIGNIFICANT REDUCTION," he captioned the length post, which read: "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."
Tom, who recently welcomed his second child with wife Kelsey, has a grade four glioblastoma, and has already undergone radiotherapy and chemotherapy treatment in a bid to prolong his life.
Tom shared a family photo on Instagram as he shared his update
Vowing to keep fighting and thanking NHS staff, Tom continued: "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.
He added: "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.
The singer revealed his diagnosis with fans in October
"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 [explicit] good day."
His bandmate and Strictly Come Dancing star Max George was one of the first to respond to the wonderful news, writing: "You got this mate... no problem!!" Rebecca Adlington added: "Yes Tom!!! What amazing words for you to hear! So pleased."
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