The star, a dancer on the show, announced in May that she had been diagnosed with breast cancer and in July said she been given a second cancer diagnosis.
She recently suffered a setback when she became ill with sepsis but is now doing better and this week returned to the BBC ballroom ahead of the new series, which kicks off in September.
Dowden shared a snap on Instagram showing her looking glamorous as she told fans that she was with her colleagues for the day and had been “Strictlyfied”.
Updating her followers after her special day, she wrote: “So grateful for my @bbcstrictly family, yesterday was just what I needed ahead of today.
“I’ve felt part of the whole journey so far!
“I’ve seen all the group numbers and the process by videos, then again watching yesterday and WOW honestly the best yet!”
The dancer went on: “Yes it’s hard not being up there with them doing what I love but so proud to part of such a talented team.
“I loved being made glamorous by the hair and make-up team, putting on a sparkly dress from wardrobe and feeling like Amy again being at my favourite place!
“So very grateful!”
Dowden, 33, told her fans that she was on her way to get her third chemotherapy treatment.
“Let’s hope no hospital admissions and scares after this one,” she said.
“But I’m going with a spring in my step this morning after yesterday and knowing everyday I’m closer to dancing on that floor again.”
Fans wished the star well after her post, saying they were “sending positive vibes” as she underwent her treatment.
Amanda Abbington, one of the celebs taking part in Strictly this year, posted: “Sending you the most love. You are FABULOUS.”
“Yes Amy!!!“ said Strictly: It Takes Two host Fleur East. “Your smile is so bright xxx.”
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