Amy Dowden said she was "so happy I could burst" after her first live Strictly Come Dancing performance since being treated for breast cancer.

The 34-year-old professional and her celebrity partner, singer JB Gill, topped the judges' leaderboard after being awarded 31 points for their waltz to When I Need You by singer Leo Sayer.

Dowden, who also danced in last week's pre-recorded launch show during which she was paired with Gill, missed the show last year after disclosing her diagnosis before undergoing chemotherapy and a mastectomy.

During Saturday's show, head judge Shirley Ballas told her: "You're home where you belong and I have to say that choreography was absolutely outstanding."

The programme was the first live show in the latest series, 20 years after the competition in its current format first aired on the BBC.

Neither of this year's shows have addressed the recent allegations by former contestants of abusive behaviour from dancing partners - which led to two professionals leaving.

Dowden, who hails from Caerphilly in Wales, was twice diagnosed with cancer last year, and has spoken previously of being desperate to return to the show.

There were also celebrations for DIY SOS star Nick Knowles, who jived with Luba Mushtuk to We Built This City by Starship on his 62nd birthday.

After their performance, Knowles was given a cake by professional dancer Carlos Gu, who appeared in a high-vis jacket and builder's hat. Gu then grabbed a piece of the cake and pushed it in Knowles' face.

Judge Anton Du Beke said Knowles' and Mushtuk's performance had been "uplifting", with them scoring them 18 points overall.

Former X Factor winner Shayne Ward and Nancy Xu danced the Samba to Do I Do by Stevie Wonder, earning them 21 points in total.

But judge Craig Revel Horwood criticised the performance, saying it "failed miserably".

He said: "It was more like a salsa... This, for me, didn't go far enough into the world of samba."

Zara McDermott was in the audience for Saturday's show, weeks after the exit of her professional dance partner, Graziano Di Prima, following reports of his treatment of her.

TV star McDermott joined the ballroom audience in support of her friend Pete Wicks, a contestant in this year's series.

Writing on Instagram after the show, she said: "Such an incredible evening. What an amazing first performance and I'm so glad I could be there to support you!!! Didn't he smash it?!?!?!"

In July, McDermott told the BBC that she had been involved in incidents during training with Di Prima that she found "incredibly distressing" to watch back.

Elsewhere, Strictly's first blind contestant, comedian Chris McCausland, was told he was "fabulous" after his performance with Dianne Buswell.

The pair performed a cha cha to Beatles hit Twist And Shout and were awarded 23 points.

Anton Du Beke said: "It was one of the most extraordinary things I've ever seen in my entire life."

Head judge Shirley Ballas said: "I'm quite shocked and very emotional - fabulous."

Former field hockey player Sam Quek and Nikita Kuzmin performed a foxtrot to Where Did Our Love Go by The Supremes, gaining 23 points.

Singer Toyah Willcox and Neil Jones danced the tango to Ray Of Light by Madonna which was also criticised by Revel Horwood and received only 12 points from the judges.

Love Island contestant Tasha Ghouri and dance partner Aljaz Skorjanec were given 30 points for their cha cha to Sabrina Carpenter's Espresso.

Skorjanec said it was a "beautiful moment" to see Ghouri, who is deaf, take off her cochlear implant towards the end of the dance so they could "just feel one another and just dance together".

TV personality Pete Wicks and Jowita Przystal danced the paso doble to Breathe by The Prodigy, netting 17 points.

Comedic actress Sarah Hadland and last year's Strictly winner Vito Coppola were awarded 30 points after their dance to Dolly Parton's 9 To 5.